GB/T 3923.1-1997 Tensile properties of textile fabrics Part 1: Determination of breaking strength and elongation at break Strip method
Some standard content:
rcs59.080-30
National Standard of the People's Republic of China
GB/T 3923.11997
Textiles
Tensile properties of fabrics
Part 1:Determination of breaking force and elongation at breaking force-Strip method
Textiles--Tensile properties of fabrics-Part 1:Determination of breaking force and elongation at breaking force-Strip 1997-06-09 Issued
1997-12-01 Implementation
Issued by the State Administration of Technical Supervision
GB/T3923.1-1997
This standard is a revision of the national standard GB3923-83 Determination of breaking strength and breaking length of woven fabrics (sampling method) . Compared with G3923-88, it has been revised in the following aspects: 1. Title and applicable scope: The title refers to the title of the international standard IS/DIS159S4.1-94, and the corresponding application is expanded, not only for woven fabrics, but also for fabrics produced by other technologies. 2. The instrument used specifies that a type of instrument should be used, namely, the CRF type strength tester. 3. Samples: It is clearly specified that the types of samples to be tested should be stripped or cut. The cutting test requirements are consistent with the return standard. 4. Tensile strength: Constant speed stretching is used, and the elongation at break of the fabric is used as the basis for determination, without considering the type of fabric. 5. Separation strength: The elongation at break of the fabric is used as the basis for determination, without considering the type of fabric. 5. Sample holding: There are two ways of holding, namely, tension clamping or tension clamping. The calculation of the breaking length of the loose-type clamped sample is different.
The tensile performance of anti-woven fabrics 3 includes two parts: Sample method:
Part I, determination of breaking strength and breaking elongation Part II, determination of breaking strength by grabbing method. This standard will replace the GB392383
rate standard and the attached date from the date of entry into force. This standard is issued by the Science and Technology Development Department of the China National Textile and Apparel Council. This standard is issued by the Standardization Research Institute of the China National Textile and Apparel Council. The unit of this standard is the National Cotton Textile Product Quality Supervision and Inspection Center. The main drafters of this standard are Wang Shu and Zheng Ziying. 1 Scope
National Standard of the People's Republic of China
Textiles
Tensile properties of fabrics
Part 1 Determination of breaking strength and elongation
Strip method
Textilcs-Tensile properties of fabrics-Part 1: Determining national strength of breaking strength and elongation at breaking--Strip method GB/R 3923.1—1997
This standard specifies the method for determining the breaking strength and elongation of fabrics by using untied strip samples and cut samples, including tests with the specimens in two states: exposed or moistened in the test standard atmosphere. This standard is applicable to fabrics produced by other technologies (knitted fabrics, solid fabrics, layered fabrics and other types of textile fabrics). This standard does not apply to elastic fabrics, flat fabrics, ribbed fabrics, technical fabrics, glass fiber fabrics, carbon fiber fabrics and ethylene-based filament fabrics. This standard specifies the use of equal elongation (CRE) test points. According to the agreement of the relevant parties, a more appropriate RT test point may be used. This should be indicated in the test report. 2 Reference standards The following provisions of the standards are read only when they are referenced in this standard and become the provisions of this standard. When this standard is published, the version shown is valid. All standards will be revised. Parties using this standard should explore the possibility of using the latest version of the following standards. GH6529-86 Standard for the conditioning and conditioning of fabrics GB8170-8 Numerical static and thermal specifications
3 Definitions
This standard uses the following definitions:
3.1 Strip test
A fabric test in which the entire width of the sample is held by a clamp. 3.2 Cut a strip
A shaped sample that is cut to a specified test length by a periodic cutting method. 3.3 Raveled strip
A shaped sample that is moved to a specified test length by removing a soft wire of substantially the same length from the sample. 3.4 Length gaugelengl
The distance between the two effective beams holding the sample on the test device. Approved by the State Administration of Industry and Information Technology on June 9, 1997, and implemented on December 1, 1997
3.5 initial length
CB/T 3923.1--1997
The distance between the two effective holding lines of the test specimen under the specified pretension. 3.6 pretension
The force applied to the test specimen before the start of the test.
3.7 breaking forcemaximum unforceThe maximum force recorded when the specimen is pulled apart during a tensile test under specified conditions. 3 breaking forceat rupture
The maximum force recorded when the specimen breaks during a tensile test under specified conditions. 3.9 elongation
The increment in length of the specimen caused by the action of the tensile force, expressed in effective length units. 3.10 Elongation
The ratio of the secondary length of the specimen to its initial length, expressed as a percentage. 3.11 Elongation at break The length of the specimen expressed as a percentage.
3.12 Elongation at break The length of the specimen expressed as a percentage of the initial length.
3.13 Constant rate of extension testing machine A testing machine in which one of the holders of the specimen is fixed and the other moves at a constant rate throughout the test, so that the elongation of the specimen is proportional to the time.
3.14 Constant rate of traverse testing machine A testing machine in which the load or the length of the specimen is increased at a rate faster than the elongation of the specimen. 4 Principle
Specimens of specified size are stretched at a specified rate of elongation until they break. The force at break and the elongation at break are recorded. If necessary, the force at break and the elongation at break are also recorded.
5 Samples
Sampling shall be carried out in accordance with the product standard of the product or in accordance with relevant agreements. In the absence of any other requirements, the sampling rules in Appendix A are recommended. 6 Test instruments and equipment
6.1 Constant rate of elongation (CRE) test instruments. The constant rate of elongation test instruments shall have the following measuring characteristics. The test position shall have an indicator to record the force at break and the corresponding rate of elongation of the sample. At any point in the full range of the test instrument, the error in the recorded breaking force shall not exceed ±1 mm. The error between the indication and the recording gap shall not exceed ±1 mm. If a digital circuit is used to obtain the force and length values, the value of the digital force gauge shall not be less than 8/min. The constant elongation rate is 20 nm/min and 1100 nm/min, and the accuracy is ±0%. The gauge length is 100 mm and 200 mm, and the warpage is ±1 mm. The center point of the measuring pliers should be on the tension axis, the jaws of the pliers should be perpendicular to the tension line, and the clamping surfaces should be on the same plane. The clamps should be able to hold the specimen without slipping. The clamping surfaces should be level and not negligible or damaging. When using a flat clamp to prevent the specimen from slipping, other forms of optical holders should be used. The holder can be made of appropriate materials, and the width of the pliers should not be less than 60 mm.
6.2 Equipment for cutting specimens.
GB/T3923.1—1997
6.3 If condensed water is brought in for testing, the test sample should be cooled with natural gas, grade 3 water, non-ionic humidifier 7, and test atmosphere.
7.1 Humidification, heat preservation and testing should be carried out in accordance with the provisions of CB6529. The test should use grade 7 standard atmosphere.2. For the test of the condensation state, no two humidity adjustment and false sources are required. 8. Test specimens
8. General
For each test sample, take a group of test specimens, one group is the longitudinal test specimen, and the other group is the transverse or horizontal test specimen. Each group of test specimens shall include at least one load-bearing test specimen and one additional test specimen. If there is a requirement for the quality of the product, the number of test specimens shall be increased: the test specimens shall be opened and the test points shall be at least 330mm. The test specimens shall be evenly spaced on the samples. For example, for the machine, the two test specimens shall not contain the same warp or weft. The Appendix shall be different from the laboratory sample. 8.2 R
The effective width of each test specimen is 50mm (excluding the hair). Its length shall be able to meet the gauge length of 20cm. If the elongation at break of the test specimen exceeds 75%, the gauge length shall be 100mm. According to the agreement between the two parties concerned, the sample may also be of other widths. In this case, during the test period,
B.3 Sample Standards
Yarn sample: for general woven fabric test. The length direction of the sample should be parallel to the warp or weft direction of the fabric, and the length should be specified with a margin of error. Cut the two strips in the length direction and remove the same number of defects until the width of the sample meets the size specified in Article 8.2. The width of the burr should ensure that the thread does not escape from the burr during the forming process. Note: for standard bridge fabrics, the burr is about 6mm5. For light and dense woven fabrics, a relatively wide burr is sufficient. For newly made woven fabrics, the burr is about 1nm.
Sample cutting: For specimens of woven fabrics, non-woven fabrics, woven fabrics with multiple layers and woven fabrics that are not easy to remove, the length direction of the specimen shall be cut parallel to the longitudinal direction or cutting direction of the fabric, and its width shall comply with the specified size in Article 8.2. 8.4 Specimens for wet test
4.1 If the fabric's ultimate strength is to be determined, the length of the entire specimen shall be twice that of the dry specimen (see Appendix 3. After the west end of each specimen is confirmed, it shall be cut into two pieces in the transverse direction, one for the determination of the ultimate strength and the other for the determination of the ultimate strength. According to experience, for fabrics with greater shrinkage after immersion in water, the length of the specimen for determining the ultimate strength shall be longer than that of the wet specimen. 4.2 The entire specimen for the wet test shall be immersed in water at a temperature of 20°C ± 2°C for more than 1 hour. An aqueous solution of a non-toxic substance with a concentration not exceeding 1 g may also be used instead. Replace the third-grade water. 9 steps
9.1 Set the gauge length
For the elongation at break less than or equal to 75%, the gauge length is 200mm±1mm. For the elongation at break greater than 75%, the gauge length is 100mm±1mm
9.2 Set the stretching speed
Based on the elongation at break or elongation of the fabric, set the stretching speed according to Table 1. Table 1 Stretching speed
Evaluation of the elongation at break
Stretching speed
mm/minu
9.3 Clamping ear sample
GB/T 3923.1—1997
Clamp the specimen in the center of the clamp to ensure that the center line of the pulling force avoids the midpoint of the clamp. The specimen can be held in the test mode under pre-tension. When the specimen is held in the pre-tension mode, the elongation rate is not more than 2%. If this cannot be guaranteed, loose clamping is adopted, i.e. no force clamping.
9.3.1 The pre-tension clamping
is used according to the unit mass of the test column. The following items are selected: $200g/m*.2N|| tt||>20cg/m*, sm.500g/m/5.Nt
2500g/m*.10N;
）When the breaking strength is lower than 20N, the tension shall be determined according to the ratio of (1 + 3.2)% of the strength. 9.3.2 The initial length of the loose clamped sample
to calculate the breaking length shall be the sum of the length at the beginning and the length at which the sample reaches the rigid tension. This length can be measured from the force-elongation curve corresponding to the pre-tension point in 3.3.1. In: Take two specimens of the same length at alternating intervals, and the one with the larger breaking length shall be the one with the larger breaking length. 9.4 Special determination
Open the tester: stretch the sample until it breaks. Record the breaking strength (unit: N), breaking elongation (unit: m/s) or breaking elongation (unit: %). If necessary, record the direction of breaking and the elongation of the breaking fracture. Test at least five pieces in each direction. If the asymmetric slip of the specimen at the joint is greater than 2 mm, the test result shall be discarded. 9.4.2 Joint new type
If the specimen breaks within 5 mT from the joint, it shall be regarded as a clamp fracture. When the five tests are completed If the value of the fracture is greater than the minimum "normal value", it should be retained. If it is less than the minimum "positive value", it should be discarded and another test should be conducted to obtain five "normal values". If all the test results are fracture, and the five "normal values" are not reached, a single value should be reported. The fracture should be indicated in the arrangement. 9.5 Wet test
Take the sample out of the chain body, put it on absorbent paper to absorb excess water, and immediately test it according to 9.1 to 9.4. The pretension is 1/2 of that specified in 9.3.1.
10 Calculation of the result
101 Calculate the average fracture strength in the longitudinal or longitudinal direction, in N, according to GB817. The break strength of a flat pin can be calculated by comparing the break strength of a flat pin with a UN value of about 0.1N and below. At 10V and less than 10N, it can be about 1N. At 100N and above, it can be effective. 10N
10.2 Use formula (1) and formula (3) to calculate the elongation at break of each specimen and express it in percentage. If necessary, use formula (2) and formula (4) to calculate the breaking length. Www.bzxZ.net
Limited tension test specimen: Elongation at break = () × 100-
Loose clamp test specimen, elongation at break = [(>/L×100 Elongation at break = [-/+100
Where: Gauge length, mm
Breaking length of pre-tension clamped specimen (see Figure 1) m; Breaking length of test specimen during test (see Figure 2), mL; Breaking length of pre-tension clamped specimen (see Figure 1). mm; A.
Breaking length of test specimen during test (see Figure 2), 10114
CB/T 3923.1-1997
The length of the test specimen when it reaches the specified pre-tension force (see Figure 2).mm. Strength
Figure 1 New tension tension or similar tension
Figure 2 Test type special tensile test
Calculate the mean value of the longitudinal or longitudinal elongation rate according to GBB170. When the average value is 8 or less, it is adjusted to 0.2%; when it is greater than 8 and less than 53, it is adjusted to 0.50% and above, and adjusted to 1%. 10.3 Calculate the coefficient of variation of the breaking strength and breaking elongation rate, which is approximately .1%. 10.4 According to Formula (5) calculates the 95% confidence interval (average value 14). The mean value is less than 1000N, rounded to 1N, and the average value is 1000N and above, rounded to 5N.
Where 5·-standard query type:
Test fee:
From the 5-distribution table. When =5, the confidence level is 95%*2.776, 11Test report
The test report should include the following:
2) Vehicle number and test date:
b) Sample name and specification;
Center length:
d) Tensile rate!
e) Sample tension, or clamping method:
) Sample shape, or recording data:
B) Number of samples, number of samples discarded, and original four! 1) Mean breaking strength and breaking length Average breaking strength and breaking length, j) 95% confidence interval for breaking strength
) If necessary, mean breaking strength and breaking length average and position! 1) Any deviation from this standard.
A1 Batch sample (number of pieces from a batch)
CB/F3923.1-1997
(Appendix to the list)
Suggested sampling procedure
Randomly select the corresponding number of pieces from a batch according to Table A1. Pieces that have been damaged or damaged during transportation cannot be used as samples. Table of batch samples
A single piece
A2. Experimental sample quantity
A small piece of batch sample
Randomly cut a full piece of at least 1m in length from each piece of the batch sample as the laboratory sample, at least 3m away from the end of the piece, to ensure that the sample has no wrinkles and obvious energy points,
(prompt recording)
Take the cut sample from the experimental case sample as an example
For the wet core test
Test long single! General
Take a group of samples from each experimental sample, one group is the longitudinal sample, the other group is the transverse or horizontal sample. Each group of samples should include the load-bearing sample, and the additional sample should be flat. If there is a requirement for the product, the sample quantity should be increased: the sample should be open for testing, and the test points should be at least 330mm. Ensure that the samples are evenly spaced on the sample. For example, for a single machine, the two missing samples should not contain the same warp or weft. The Appendix is not allowed to distinguish the samples from the laboratory samples. 8.2 R
The effective width of each sample is 50mm (excluding the hair). Its length should be able to meet the gauge length of 20cm. If the elongation at break of the sample exceeds 75%, the gauge length should be set to 100mm. According to the agreement between the two parties concerned, the sample may also be of other widths. In this case, during the test period,
B.3 Sample Standards
Yarn sample: for general woven fabric test. The length direction of the sample should be parallel to the warp or weft direction of the fabric, and the length should be specified with a margin of error. Cut the two strips in the length direction and remove the same number of defects until the width of the sample meets the size specified in Article 8.2. The width of the burr should ensure that the thread does not escape from the burr during the forming process. Note: for standard bridge fabrics, the burr is about 6mm5. For light and dense woven fabrics, a relatively wide burr is sufficient. For newly made woven fabrics, the burr is about 1nm.
Sample cutting: For specimens of woven fabrics, non-woven fabrics, woven fabrics with multiple layers and woven fabrics that are not easy to remove, the length direction of the specimen shall be cut parallel to the longitudinal direction or cutting direction of the fabric, and its width shall comply with the specified size in Article 8.2. 8.4 Specimens for wet test
4.1 If the fabric's ultimate strength is to be determined, the length of the entire specimen shall be twice that of the dry specimen (see Appendix 3. After the west end of each specimen is confirmed, it shall be cut into two pieces in the transverse direction, one for the determination of the ultimate strength and the other for the determination of the ultimate strength. According to experience, for fabrics with greater shrinkage after immersion in water, the length of the specimen for determining the ultimate strength shall be longer than that of the wet specimen. 4.2 The entire specimen for the wet test shall be immersed in water at a temperature of 20°C ± 2°C for more than 1 hour. An aqueous solution of a non-toxic substance with a concentration not exceeding 1 g may also be used instead. Replace the third-grade water. 9 steps
9.1 Set the gauge length
For the elongation at break less than or equal to 75%, the gauge length is 200mm±1mm. For the elongation at break greater than 75%, the gauge length is 100mm±1mm
9.2 Set the stretching speed
Based on the elongation at break or elongation of the fabric, set the stretching speed according to Table 1. Table 1 Stretching speed
Evaluation of the elongation at break
Stretching speed
mm/minu
9.3 Clamping ear sample
GB/T 3923.1—1997
Clamp the specimen in the center of the clamp to ensure that the center line of the pulling force avoids the midpoint of the clamp. The specimen can be held in the test mode under pre-tension. When the specimen is held in the pre-tension mode, the elongation rate is not more than 2%. If this cannot be guaranteed, loose clamping is adopted, i.e. no force clamping.
9.3.1 The pre-tension clamping
is used according to the unit mass of the test column. The following items are selected: $200g/m*.2N|| tt||>20cg/m*, sm.500g/m/5.Nt
2500g/m*.10N;
）When the breaking strength is lower than 20N, the tension shall be determined according to the ratio of (1 + 3.2)% of the strength. 9.3.2 The initial length of the loose clamped sample
to calculate the breaking length shall be the sum of the length at the beginning and the length at which the sample reaches the rigid tension. This length can be measured from the force-elongation curve corresponding to the pre-tension point in 3.3.1. In: Take two specimens of the same length at alternating intervals, and the one with the larger breaking length shall be the one with the larger breaking length. 9.4 Special determination
Open the tester: stretch the sample until it breaks. Record the breaking strength (unit: N), breaking elongation (unit: m/s) or breaking elongation (unit: %). If necessary, record the direction of breaking and the elongation of the breaking fracture. Test at least five pieces in each direction. If the asymmetric slip of the specimen at the joint is greater than 2 mm, the test result shall be discarded. 9.4.2 Joint new type
If the specimen breaks within 5 mT from the joint, it shall be regarded as a clamp fracture. When the five tests are completed If the value of the fracture is greater than the minimum "normal value", it should be retained. If it is less than the minimum "positive value", it should be discarded and another test should be conducted to obtain five "normal values". If all the test results are fracture, and the five "normal values" are not reached, a single value should be reported. The fracture should be indicated in the arrangement. 9.5 Wet test
Take the sample out of the chain body, put it on absorbent paper to absorb excess water, and immediately test it according to 9.1 to 9.4. The pretension is 1/2 of that specified in 9.3.1.
10 Calculation of the result
101 Calculate the average fracture strength in the longitudinal or longitudinal direction, in N, according to GB817. The break strength of a flat pin can be calculated by comparing the break strength of a flat pin with a UN value of about 0.1N and below. At 10V and less than 10N, it can be about 1N. At 100N and above, it can be effective. 10N
10.2 Use formula (1) and formula (3) to calculate the elongation at break of each specimen and express it in percentage. If necessary, use formula (2) and formula (4) to calculate the breaking length.
Limited tension test specimen: Elongation at break = () × 100-
Loose clamp test specimen, elongation at break = [(>/L×100 Elongation at break = [-/+100
Where: Gauge length, mm
Breaking length of pre-tension clamped specimen (see Figure 1) m; Breaking length of test specimen during test (see Figure 2), mL; Breaking length of pre-tension clamped specimen (see Figure 1). mm; A.
Breaking length of test specimen during test (see Figure 2), 10114
CB/T 3923.1-1997
The length of the test specimen when it reaches the specified pre-tension force (see Figure 2).mm. Strength
Figure 1 New tension tension or similar tension
Figure 2 Test type special tensile test
Calculate the mean value of the longitudinal or longitudinal elongation rate according to GBB170. When the average value is 8 or less, it is adjusted to 0.2%; when it is greater than 8 and less than 53, it is adjusted to 0.50% and above, and adjusted to 1%. 10.3 Calculate the coefficient of variation of the breaking strength and breaking elongation rate, which is approximately .1%. 10.4 According to Formula (5) calculates the 95% confidence interval (average value 14). The mean value is less than 1000N, rounded to 1N, and the average value is 1000N and above, rounded to 5N.
Where 5·-standard query type:
Test fee:
From the 5-distribution table. When =5, the confidence level is 95%*2.776, 11Test report
The test report should include the following:
2) Vehicle number and test date:
b) Sample name and specification;
Center length:
d) Tensile rate!
e) Sample tension, or clamping method:
) Sample shape, or recording data:
B) Number of samples, number of samples discarded, and original four! 1) Mean breaking strength and breaking length Average breaking strength and breaking length, j) 95% confidence interval for breaking strength
) If necessary, mean breaking strength and breaking length average and position! 1) Any deviation from this standard.
A1 Batch sample (number of pieces from a batch)
CB/F3923.1-1997
(Appendix to the list)
Suggested sampling procedure
Randomly select the corresponding number of pieces from a batch according to Table A1. Pieces that have been damaged or damaged during transportation cannot be used as samples. Table of batch samples
A single piece
A2. Experimental sample quantity
A small piece of batch sample
Randomly cut a full piece of at least 1m in length from each piece of the batch sample as the laboratory sample, at least 3m away from the end of the piece, to ensure that the sample has no wrinkles and obvious energy points,
(prompt recording)
Take the cut sample from the experimental case sample as an example
For the wet core test
Test long single! General
Take a group of samples from each experimental sample, one group is the longitudinal sample, the other group is the transverse or horizontal sample. Each group of samples should include the load-bearing sample, and the additional sample should be flat. If there is a requirement for the product, the sample quantity should be increased: the sample should be open for testing, and the test points should be at least 330mm. Ensure that the samples are evenly spaced on the sample. For example, for a single machine, the two missing samples should not contain the same warp or weft. The Appendix is not allowed to distinguish the samples from the laboratory samples. 8.2 R
The effective width of each sample is 50mm (excluding the hair). Its length should be able to meet the gauge length of 20cm. If the elongation at break of the sample exceeds 75%, the gauge length should be set to 100mm. According to the agreement between the two parties concerned, the sample may also be of other widths. In this case, during the test period,
B.3 Sample Standards
Yarn sample: for general woven fabric test. The length direction of the sample should be parallel to the warp or weft direction of the fabric, and the length should be specified with a margin of error. Cut the two strips in the length direction and remove the same number of defects until the width of the sample meets the size specified in Article 8.2. The width of the burr should ensure that the thread does not escape from the burr during the forming process. Note: for standard bridge fabrics, the burr is about 6mm5. For light and dense woven fabrics, a relatively wide burr is sufficient. For newly made woven fabrics, the burr is about 1nm.
Sample cutting: For specimens of woven fabrics, non-woven fabrics, woven fabrics with multiple layers and woven fabrics that are not easy to remove, the length direction of the specimen shall be cut parallel to the longitudinal direction or cutting direction of the fabric, and its width shall comply with the specified size in Article 8.2. 8.4 Specimens for wet test
4.1 If the fabric's ultimate strength is to be determined, the length of the entire specimen shall be twice that of the dry specimen (see Appendix 3. After the west end of each specimen is confirmed, it shall be cut into two pieces in the transverse direction, one for the determination of the ultimate strength and the other for the determination of the ultimate strength. According to experience, for fabrics with greater shrinkage after immersion in water, the length of the specimen for determining the ultimate strength shall be longer than that of the wet specimen. 4.2 The entire specimen for the wet test shall be immersed in water at a temperature of 20°C ± 2°C for more than 1 hour. An aqueous solution of a non-toxic substance with a concentration not exceeding 1 g may also be used instead. Replace the third-grade water. 9 steps
9.1 Set the gauge length
For the elongation at break less than or equal to 75%, the gauge length is 200mm±1mm. For the elongation at break greater than 75%, the gauge length is 100mm±1mm
9.2 Set the stretching speed
Based on the elongation at break or elongation of the fabric, set the stretching speed according to Table 1. Table 1 Stretching speed
Evaluation of the elongation at break
Stretching speed
mm/minu
9.3 Clamping ear sample
GB/T 3923.1—1997
Clamp the specimen in the center of the clamp to ensure that the center line of the pulling force avoids the midpoint of the clamp. The specimen can be held in the test mode under pre-tension. When the specimen is held in the pre-tension mode, the elongation rate is not more than 2%. If this cannot be guaranteed, loose clamping is adopted, i.e. no force clamping.
9.3.1 The pre-tension clamping
is used according to the unit mass of the test column. The following items are selected: $200g/m*.2N|| tt||>20cg/m*, sm.500g/m/5.Nt
2500g/m*.10N;
）When the breaking strength is lower than 20N, the tension shall be determined according to the ratio of (1 + 3.2)% of the strength. 9.3.2 The initial length of the loose clamped sample
to calculate the breaking length shall be the sum of the length at the beginning and the length at which the sample reaches the rigid tension. This length can be measured from the force-elongation curve corresponding to the pre-tension point in 3.3.1. In: Take two specimens of the same length at alternating intervals, and the one with the larger breaking length shall be the one with the larger breaking length. 9.4 Special determination
Open the tester: stretch the sample until it breaks. Record the breaking strength (unit: N), breaking elongation (unit: m/s) or breaking elongation (unit: %). If necessary, record the direction of breaking and the elongation of the breaking fracture. Test at least five pieces in each direction. If the asymmetric slip of the specimen at the joint is greater than 2 mm, the test result shall be discarded. 9.4.2 Joint new type
If the specimen breaks within 5 mT from the joint, it shall be regarded as a clamp fracture. When the five tests are completed If the value of the fracture is greater than the minimum "normal value", it should be retained. If it is less than the minimum "positive value", it should be discarded and another test should be conducted to obtain five "normal values". If all the test results are fracture, and the five "normal values" are not reached, a single value should be reported. The fracture should be indicated in the arrangement. 9.5 Wet test
Take the sample out of the chain body, put it on absorbent paper to absorb excess water, and immediately test it according to 9.1 to 9.4. The pretension is 1/2 of that specified in 9.3.1.
10 Calculation of the result
101 Calculate the average fracture strength in the longitudinal or longitudinal direction, in N, according to GB817. The break strength of a flat pin can be calculated by comparing the break strength of a flat pin with a UN value of about 0.1N and below. At 10V and less than 10N, it can be about 1N. At 100N and above, it can be effective. 10N
10.2 Use formula (1) and formula (3) to calculate the elongation at break of each specimen and express it in percentage. If necessary, use formula (2) and formula (4) to calculate the breaking length.
Limited tension test specimen: Elongation at break = () × 100-
Loose clamp test specimen, elongation at break = [(>/L×100 Elongation at break = [-/+100
Where: Gauge length, mm
Breaking length of pre-tension clamped specimen (see Figure 1) m; Breaking length of test specimen during test (see Figure 2), mL; Breaking length of pre-tension clamped specimen (see Figure 1). mm; A.
Breaking length of test specimen during test (see Figure 2), 10114
CB/T 3923.1-1997
The length of the test specimen when it reaches the specified pre-tension force (see Figure 2).mm. Strength
Figure 1 New tension tension or similar tension
Figure 2 Test type special tensile test
Calculate the mean value of the longitudinal or longitudinal elongation rate according to GBB170. When the average value is 8 or less, it is adjusted to 0.2%; when it is greater than 8 and less than 53, it is adjusted to 0.50% and above, and adjusted to 1%. 10.3 Calculate the coefficient of variation of the breaking strength and breaking elongation rate, which is approximately .1%. 10.4 According to Formula (5) calculates the 95% confidence interval (average value 14). The mean value is less than 1000N, rounded to 1N, and the average value is 1000N and above, rounded to 5N.
Where 5·-standard query type:
Test fee:
From the 5-distribution table. When =5, the confidence level is 95%*2.776, 11Test report
The test report should include the following:
2) Vehicle number and test date:
b) Sample name and specification;
Center length:
d) Tensile rate!
e) Sample tension, or clamping method:
) Sample shape, or recording data:
B) Number of samples, number of samples discarded, and original four! 1) Mean breaking strength and breaking length Average breaking strength and breaking length, j) 95% confidence interval for breaking strength
) If necessary, mean breaking strength and breaking length average and position! 1) Any deviation from this standard.
A1 Batch sample (number of pieces from a batch)
CB/F3923.1-1997
(Appendix to the list)
Suggested sampling procedure
Randomly select the corresponding number of pieces from a batch according to Table A1. Pieces that have been damaged or damaged during transportation cannot be used as samples. Table of batch samples
A single piece
A2. Experimental sample quantity
A small piece of batch sample
Randomly cut a full piece of at least 1m in length from each piece of the batch sample as the laboratory sample, at least 3m away from the end of the piece, to ensure that the sample has no wrinkles and obvious energy points,
(prompt recording)
Take the cut sample from the experimental case sample as an example
For the wet core test
Test long single2 R
Each sample has an effective width of 50mm (excluding wool). Its length should be able to meet the gauge length of 20cm. If the elongation at break of the sample exceeds 75%, the gauge length should be set to 100mm. According to the agreement between the two parties concerned, the sample can also be of other width. In this case, in the test period,
B.3 Sample standard
Yarn sample: used for general woven fabric test. The length direction of the sample should be parallel to the warp or tie of the fabric, and the length of the sample should be left with the length of the wool. Cut the two sides of the length direction of the strip sample and remove the defects of equal number until the width of the sample meets the size specified in Article 8.2. The width of the burr should ensure that the thread does not escape from the burr during the forming process. Note: for standard bridge fabrics, the burr is about 6mm5. For light and dense woven fabrics, a relatively wide burr is sufficient. For newly made woven fabrics, the burr is about 1nm.
Sample cutting: For specimens of woven fabrics, non-woven fabrics, woven fabrics with multiple layers and woven fabrics that are not easy to remove, the length direction of the specimen shall be cut parallel to the longitudinal direction or cutting direction of the fabric, and its width shall comply with the specified size in Article 8.2. 8.4 Specimens for wet test
4.1 If the fabric's ultimate strength is to be determined, the length of the entire specimen shall be twice that of the dry specimen (see Appendix 3. After the west end of each specimen is confirmed, it shall be cut into two pieces in the transverse direction, one for the determination of the ultimate strength and the other for the determination of the ultimate strength. According to experience, for fabrics with greater shrinkage after immersion in water, the length of the specimen for determining the ultimate strength shall be longer than that of the wet specimen. 4.2 The entire specimen for the wet test shall be immersed in water at a temperature of 20°C ± 2°C for more than 1 hour. An aqueous solution of a non-toxic substance with a concentration not exceeding 1 g may also be used instead. Replace the third-grade water. 9 steps
9.1 Set the gauge length
For the elongation at break less than or equal to 75%, the gauge length is 200mm±1mm. For the elongation at break greater than 75%, the gauge length is 100mm±1mm
9.2 Set the stretching speed
Based on the elongation at break or elongation of the fabric, set the stretching speed according to Table 1. Table 1 Stretching speed
Evaluation of the elongation at break
Stretching speed
mm/minu
9.3 Clamping ear sample
GB/T 3923.1—1997
Clamp the specimen in the center of the clamp to ensure that the center line of the pulling force avoids the midpoint of the clamp. The specimen can be held in the test mode under pre-tension. When the specimen is held in the pre-tension mode, the elongation rate is not more than 2%. If this cannot be guaranteed, loose clamping is adopted, i.e. no force clamping.
9.3.1 The pre-tension clamping
is used according to the unit mass of the test column. The following items are selected: $200g/m*.2N|| tt||>20cg/m*, sm.500g/m/5.Nt
2500g/m*.10N;
）When the breaking strength is lower than 20N, the tension shall be determined according to the ratio of (1 + 3.2)% of the strength. 9.3.2 The initial length of the loose clamped sample
to calculate the breaking length shall be the sum of the length at the beginning and the length at which the sample reaches the rigid tension. This length can be measured from the force-elongation curve corresponding to the pre-tension point in 3.3.1. In: Take two specimens of the same length at alternating intervals, and the one with the larger breaking length shall be the one with the larger breaking length. 9.4 Special determination
Open the tester: stretch the sample until it breaks. Record the breaking strength (unit: N), breaking elongation (unit: m/s) or breaking elongation (unit: %). If necessary, record the direction of breaking and the elongation of the breaking fracture. Test at least five pieces in each direction. If the asymmetric slip of the specimen at the joint is greater than 2 mm, the test result shall be discarded. 9.4.2 Joint new type
If the specimen breaks within 5 mT from the joint, it shall be regarded as a clamp fracture. When the five tests are completed If the value of the fracture is greater than the minimum "normal value", it should be retained. If it is less than the minimum "positive value", it should be discarded and another test should be conducted to obtain five "normal values". If all the test results are fracture, and the five "normal values" are not reached, a single value should be reported. The fracture should be indicated in the arrangement. 9.5 Wet test
Take the sample out of the chain body, put it on absorbent paper to absorb excess water, and immediately test it according to 9.1 to 9.4. The pretension is 1/2 of that specified in 9.3.1.
10 Calculation of the result
101 Calculate the average fracture strength in the longitudinal or longitudinal direction, in N, according to GB817. The break strength of a flat pin can be calculated by comparing the break strength of a flat pin with a UN value of about 0.1N and below. At 10V and less than 10N, it can be about 1N. At 100N and above, it can be effective. 10N
10.2 Use formula (1) and formula (3) to calculate the elongation at break of each specimen and express it in percentage. If necessary, use formula (2) and formula (4) to calculate the breaking length.
Limited tension test specimen: Elongation at break = () × 100-
Loose clamp test specimen, elongation at break = [(>/L×100 Elongation at break = [-/+100
Where: Gauge length, mm
Breaking length of pre-tension clamped specimen (see Figure 1) m; Breaking length of test specimen during test (see Figure 2), mL; Breaking length of pre-tension clamped specimen (see Figure 1). mm; A.
Breaking length of test specimen during test (see Figure 2), 10114
CB/T 3923.1-1997
The length of the test specimen when it reaches the specified pre-tension force (see Figure 2).mm. Strength
Figure 1 New tension tension or similar tension
Figure 2 Test type special tensile test
Calculate the mean value of the longitudinal or longitudinal elongation rate according to GBB170. When the average value is 8 or less, it is adjusted to 0.2%; when it is greater than 8 and less than 53, it is adjusted to 0.50% and above, and adjusted to 1%. 10.3 Calculate the coefficient of variation of the breaking strength and breaking elongation rate, which is approximately .1%. 10.4 According to Formula (5) calculates the 95% confidence interval (average value 14). The mean value is less than 1000N, rounded to 1N, and the average value is 1000N and above, rounded to 5N.
Where 5·-standard query type:
Test fee:
From the 5-distribution table. When =5, the confidence level is 95%*2.776, 11Test report
The test report should include the following:
2) Vehicle number and test date:
b) Sample name and specification;
Center length:
d) Tensile rate!
e) Sample tension, or clamping method:
) Sample shape, or recording data:
B) Number of samples, number of samples discarded, and original four! 1) Mean breaking strength and breaking length Average breaking strength and breaking length, j) 95% confidence interval for breaking strength
) If necessary, mean breaking strength and breaking length average and position! 1) Any deviation from this standard.
A1 Batch sample (number of pieces from a batch)
CB/F3923.1-1997
(Appendix to the list)
Suggested sampling procedure
Randomly select the corresponding number of pieces from a batch according to Table A1. Pieces that have been damaged or damaged during transportation cannot be used as samples. Table of batch samples
A single piece
A2. Experimental sample quantity
A small piece of batch sample
Randomly cut a full piece of at least 1m in length from each piece of the batch sample as the laboratory sample, at least 3m away from the end of the piece, to ensure that the sample has no wrinkles and obvious energy points,
(prompt recording)
Take the cut sample from the experimental case sample as an example
For the wet core test
Test long single2 R
Each sample has an effective width of 50mm (excluding wool). Its length should be able to meet the gauge length of 20cm. If the elongation at break of the sample exceeds 75%, the gauge length should be set to 100mm. According to the agreement between the two parties concerned, the sample can also be of other width. In this case, in the test period,
B.3 Sample standard
Yarn sample: used for general woven fabric test. The length direction of the sample should be parallel to the warp or tie of the fabric, and the length of the sample should be left with the length of the wool. Cut the two sides of the length direction of the strip sample and remove the defects of equal number until the width of the sample meets the size specified in Article 8.2. The width of the burr should ensure that the thread does not escape from the burr during the forming process. Note: for standard bridge fabrics, the burr is about 6mm5. For light and dense woven fabrics, a relatively wide burr is sufficient. For newly made woven fabrics, the burr is about 1nm.
Sample cutting: For specimens of woven fabrics, non-woven fabrics, woven fabrics with multiple layers and woven fabrics that are not easy to remove, the length direction of the specimen shall be cut parallel to the longitudinal direction or cutting direction of the fabric, and its width shall comply with the specified size in Article 8.2. 8.4 Specimens for wet test
4.1 If the fabric's ultimate strength is to be determined, the length of the entire specimen shall be twice that of the dry specimen (see Appendix 3. After the west end of each specimen is confirmed, it shall be cut into two pieces in the transverse direction, one for the determination of the ultimate strength and the other for the determination of the ultimate strength. According to experience, for fabrics with greater shrinkage after immersion in water, the length of the specimen for determining the ultimate strength shall be longer than that of the wet specimen. 4.2 The entire specimen for the wet test shall be immersed in water at a temperature of 20°C ± 2°C for more than 1 hour. An aqueous solution of a non-toxic substance with a concentration not exceeding 1 g may also be used instead. Replace the third-grade water. 9 steps
9.1 Set the gauge length
For the elongation at break less than or equal to 75%, the gauge length is 200mm±1mm. For the elongation at break greater than 75%, the gauge length is 100mm±1mm
9.2 Set the stretching speed
Based on the elongation at break or elongation of the fabric, set the stretching speed according to Table 1. Table 1 Stretching speed
Evaluation of the elongation at break
Stretching speed
mm/minu
9.3 Clamping ear sample
GB/T 3923.1—1997
Clamp the specimen in the center of the clamp to ensure that the center line of the pulling force avoids the midpoint of the clamp. The specimen can be held in the test mode under pre-tension. When the specimen is held in the pre-tension mode, the elongation rate is not more than 2%. If this cannot be guaranteed, loose clamping is adopted, i.e. no force clamping.
9.3.1 The pre-tension clamping
is used according to the unit mass of the test column. The following items are selected: $200g/m*.2N|| tt||>20cg/m*, sm.500g/m/5.Nt
2500g/m*.10N;
）When the breaking strength is lower than 20N, the tension shall be determined according to the ratio of (1 + 3.2)% of the strength. 9.3.2 The initial length of the loose clamped sample
to calculate the breaking length shall be the sum of the length at the beginning and the length at which the sample reaches the rigid tension. This length can be measured from the force-elongation curve corresponding to the pre-tension point in 3.3.1. In: Take two specimens of the same length at alternating intervals, and the one with the larger breaking length shall be the one with the larger breaking length. 9.4 Special determination
Open the tester: stretch the sample until it breaks. Record the breaking strength (unit: N), breaking elongation (unit: m/s) or breaking elongation (unit: %). If necessary, record the direction of breaking and the elongation of the breaking fracture. Test at least five pieces in each direction. If the asymmetric slip of the specimen at the joint is greater than 2 mm, the test result shall be discarded. 9.4.2 Joint new type
If the specimen breaks within 5 mT from the joint, it shall be regarded as a clamp fracture. When the five tests are completed If the value of the fracture is greater than the minimum "normal value", it should be retained. If it is less than the minimum "positive value", it should be discarded and another test should be conducted to obtain five "normal values". If all the test results are fracture, and the five "normal values" are not reached, a single value should be reported. The fracture should be indicated in the arrangement. 9.5 Wet test
Take the sample out of the chain body, put it on absorbent paper to absorb excess water, and immediately test it according to 9.1 to 9.4. The pretension is 1/2 of that specified in 9.3.1.
10 Calculation of the result
101 Calculate the average fracture strength in the longitudinal or longitudinal direction, in N, according to GB817. The break strength of a flat pin can be calculated by comparing the break strength of a flat pin with a UN value of about 0.1N and below. At 10V and less than 10N, it can be about 1N. At 100N and above, it can be effective. 10N
10.2 Use formula (1) and formula (3) to calculate the elongation at break of each specimen and express it in percentage. If necessary, use formula (2) and formula (4) to calculate the breaking length.
Limited tension test specimen: Elongation at break = () × 100-
Loose clamp test specimen, elongation at break = [(>/L×100 Elongation at break = [-/+100
Where: Gauge length, mm
Breaking length of pre-tension clamped specimen (see Figure 1) m; Breaking length of test specimen during test (see Figure 2), mL; Breaking length of pre-tension clamped specimen (see Figure 1). mm; A.
Breaking length of test specimen during test (see Figure 2), 10114
CB/T 3923.1-1997
The length of the test specimen when it reaches the specified pre-tension force (see Figure 2).mm. Strength
Figure 1 New tension tension or similar tension
Figure 2 Test type special tensile test
Calculate the mean value of the longitudinal or longitudinal elongation rate according to GBB170. When the average value is 8 or less, it is adjusted to 0.2%; when it is greater than 8 and less than 53, it is adjusted to 0.50% and above, and adjusted to 1%. 10.3 Calculate the coefficient of variation of the breaking strength and breaking elongation rate, which is approximately .1%. 10.4 According to Formula (5) calculates the 95% confidence interval (average value 14). The mean value is less than 1000N, rounded to 1N, and the average value is 1000N and above, rounded to 5N.
Where 5·-standard query type:
Test fee:
From the 5-distribution table. When =5, the confidence level is 95%*2.776, 11Test report
The test report should include the following:
2) Vehicle number and test date:
b) Sample name and specification;
Center length:
d) Tensile rate!
e) Sample tension, or clamping method:
) Sample shape, or recording data:
B) Number of samples, number of samples discarded, and original four! 1) Mean breaking strength and breaking length Average breaking strength and breaking length, j) 95% confidence interval for breaking strength
) If necessary, mean breaking strength and breaking length average and position! 1) Any deviation from this standard.
A1 Batch sample (number of pieces from a batch)
CB/F3923.1-1997
(Appendix to the list)
Suggested sampling procedure
Randomly select the corresponding number of pieces from a batch according to Table A1. Pieces that have been damaged or damaged during transportation cannot be used as samples. Table of batch samples
A single piece
A2. Experimental sample quantity
A small piece of batch sample
Randomly cut a full piece of at least 1m in length from each piece of the batch sample as the laboratory sample, at least 3m away from the end of the piece, to ensure that the sample has no wrinkles and obvious energy points,
(prompt recording)
Take the cut sample from the experimental case sample as an example
For the wet core test
Test long single2. The width of the edge should ensure that the wire does not escape from the burr during the forming process. Note: For standard bridge fabrics, the burr is about 6mm. For light and dense woven fabrics, a relatively small burr is sufficient. For newly finished woven fabrics, the burr is about 1mm.
Sample cutting: For fabrics, non-woven fabrics, woven fabrics that are not easy to remove, the length direction of the sample is cut parallel to the longitudinal direction or cutting direction of the fabric, and its width meets the size specified in Article 8.2. 8.4 Specimens for wet test
4.1 If the fabric's ultimate strength is to be determined, the length of the entire specimen shall be twice that of the dry specimen (see Appendix 3. After the west end of each specimen is confirmed, it shall be cut into two pieces in the transverse direction, one for the determination of the ultimate strength and the other for the determination of the ultimate strength. According to experience, for fabrics with greater shrinkage after immersion in water, the length of the specimen for determining the ultimate strength shall be longer than that of the wet specimen. 4.2 The entire specimen for the wet test shall be immersed in water at a temperature of 20°C ± 2°C for more than 1 hour. An aqueous solution of a non-toxic substance with a concentration not exceeding 1 g may also be used instead. Replace the third-grade water. 9 steps
9.1 Set the gauge length
For the elongation at break less than or equal to 75%, the gauge length is 200mm±1mm. For the elongation at break greater than 75%, the gauge length is 100mm±1mm
9.2 Set the stretching speed
Based on the elongation at break or elongation of the fabric, set the stretching speed according to Table 1. Table 1 Stretching speed
Evaluation of the elongation at break
Stretching speed
mm/minu
9.3 Clamping ear sample
GB/T 3923.1—1997
Clamp the specimen in the center of the clamp to ensure that the center line of the pulling force avoids the midpoint of the clamp. The specimen can be held in the test mode under pre-tension. When the specimen is held in the pre-tension mode, the elongation rate is not more than 2%. If this cannot be guaranteed, loose clamping is adopted, i.e. no force clamping.
9.3.1 The pre-tension clamping
is used according to the unit mass of the test column. The following items are selected: $200g/m*.2N|| tt||>20cg/m*, sm.500g/m/5.Nt
2500g/m*.10N;
）When the breaking strength is lower than 20N, the tension shall be determined according to the ratio of (1 + 3.2)% of the strength. 9.3.2 The initial length of the loose clamped sample
to calculate the breaking length shall be the sum of the length at the beginning and the length at which the sample reaches the rigid tension. This length can be measured from the force-elongation curve corresponding to the pre-tension point in 3.3.1. In: Take two specimens of the same length at alternating intervals, and the one with the larger breaking length shall be the one with the larger breaking length. 9.4 Special determination
Open the tester: stretch the sample until it breaks. Record the breaking strength (unit: N), breaking elongation (unit: m/s) or breaking elongation (unit: %). If necessary, record the direction of breaking and the elongation of the breaking fracture. Test at least five pieces in each direction. If the asymmetric slip of the specimen at the joint is greater than 2 mm, the test result shall be discarded. 9.4.2 Joint new type
If the specimen breaks within 5 mT from the joint, it shall be regarded as a clamp fracture. When the five tests are completed If the value of the fracture is greater than the minimum "normal value", it should be retained. If it is less than the minimum "positive value", it should be discarded and another test should be conducted to obtain five "normal values". If all the test results are fracture, and the five "normal values" are not reached, a single value should be reported. The fracture should be indicated in the arrangement. 9.5 Wet test
Take the sample out of the chain body, put it on absorbent paper to absorb excess water, and immediately test it according to 9.1 to 9.4. The pretension is 1/2 of that specified in 9.3.1.
10 Calculation of the result
101 Calculate the average fracture strength in the longitudinal or longitudinal direction, in N, according to GB817. The break strength of a flat pin can be calculated by comparing the break strength of a flat pin with a UN value of about 0.1N and below. At 10V and less than 10N, it can be about 1N. At 100N and above, it can be effective. 10N
10.2 Use formula (1) and formula (3) to calculate the elongation at break of each specimen and express it in percentage. If necessary, use formula (2) and formula (4) to calculate the breaking length.
Limited tension test specimen: Elongation at break = () × 100-
Loose clamp test specimen, elongation at break = [(>/L×100 Elongation at break = [-/+100
Where: Gauge length, mm
Breaking length of pre-tension clamped specimen (see Figure 1) m; Breaking length of test specimen during test (see Figure 2), mL; Breaking length of pre-tension clamped specimen (see Figure 1). mm; A.
Breaking length of test specimen during test (see Figure 2), 10114
CB/T 3923.1-1997
The length of the test specimen when it reaches the specified pre-tension force (see Figure 2).mm. Strength
Figure 1 New tension tension or similar tension
Figure 2 Test type special tensile test
Calculate the mean value of the longitudinal or longitudinal elongation rate according to GBB170. When the average value is 8 or less, it is adjusted to 0.2%; when it is greater than 8 and less than 53, it is adjusted to 0.50% and above, and adjusted to 1%. 10.3 Calculate the coefficient of variation of the breaking strength and breaking elongation rate, which is approximately .1%. 10.4 According to Formula (5) calculates the 95% confidence interval (average value 14). The mean value is less than 1000N, rounded to 1N, and the average value is 1000N and above, rounded to 5N.
Where 5·-standard query type:
Test fee:
From the 5-distribution table. When =5, the confidence level is 95%*2.776, 11Test report
The test report should include the following:
2) Vehicle number and test date:
b) Sample name and specification;
Center length:
d) Tensile rate!
e) Sample tension, or clamping method:
) Sample shape, or recording data:
B) Number of samples, number of samples discarded, and original four! 1) Mean breaking strength and breaking length Average breaking strength and breaking length, j) 95% confidence interval for breaking strength
) If necessary, mean breaking strength and breaking length average and position! 1) Any deviation from this standard.
A1 Batch sample (number of pieces from a batch)
CB/F3923.1-1997
(Appendix to the list)
Suggested sampling procedure
Randomly select the corresponding number of pieces from a batch according to Table A1. Pieces that have been damaged or damaged during transportation cannot be used as samples. Table of batch samples
A single piece
A2. Experimental sample quantity
A small piece of batch sample
Randomly cut a full piece of at least 1m in length from each piece of the batch sample as the laboratory sample, at least 3m away from the end of the piece, to ensure that the sample has no wrinkles and obvious energy points,
(prompt recording)
Take the cut sample from the experimental case sample as an example
For the wet core test
Test long single2. The width of the edge should ensure that the wire does not escape from the burr during the forming process. Note: For standard bridge fabrics, the burr is about 6mm. For light and dense woven fabrics, a relatively small burr is sufficient. For newly finished woven fabrics, the burr is about 1mm.
Sample cutting: For fabrics, non-woven fabrics, woven fabrics that are not easy to remove, the length direction of the sample is cut parallel to the longitudinal direction or cutting direction of the fabric, and its width meets the size specified in Article 8.2. 8.4 Specimens for wet test
4.1 If the fabric's ultimate strength is to be determined, the length of the entire specimen shall be twice that of the dry specimen (see Appendix 3. After the west end of each specimen is confirmed, it shall be cut into two pieces in the transverse direction, one for the determination of the ultimate strength and the other for the determination of the ultimate strength. According to experience, for fabrics with greater shrinkage after immersion in water, the length of the specimen for determining the ultimate strength shall be longer than that of the wet specimen. 4.2 The entire specimen for the wet test shall be immersed in water at a temperature of 20°C ± 2°C for more than 1 hour. An aqueous solution of a non-toxic substance with a concentration not exceeding 1 g may also be used instead. Replace the third-grade water. 9 steps
9.1 Set the gauge length
For the elongation at break less than or equal to 75%, the gauge length is 200mm±1mm. For the elongation at break greater than 75%, the gauge length is 100mm±1mm
9.2 Set the stretching speed
Based on the elongation at break or elongation of the fabric, set the stretching speed according to Table 1. Table 1 Stretching speed
Evaluation of the elongation at break
Stretching speed
mm/minu
9.3 Clamping ear sample
GB/T 3923.1—1997
Clamp the specimen in the center of the clamp to ensure that the center line of the pulling force avoids the midpoint of the clamp. The specimen can be held in the test mode under pre-tension. When the specimen is held in the pre-tension mode, the elongation rate is not more than 2%. If this cannot be guaranteed, loose clamping is adopted, i.e. no force clamping.
9.3.1 The pre-tension clamping
is used according to the unit mass of the test column. The following items are selected: $200g/m*.2N|| tt||>20cg/m*, sm.500g/m/5.Nt
2500g/m*.10N;
）When the breaking strength is lower than 20N, the tension shall be determined according to the ratio of (1 + 3.2)% of the strength. 9.3.2 The initial length of the loose clamped sample
to calculate the breaking length shall be the sum of the length at the beginning and the length at which the sample reaches the rigid tension. This length can be measured from the force-elongation curve corresponding to the pre-tension point in 3.3.1. In: Take two specimens of the same length at alternating intervals, and the one with the larger breaking length shall be the one with the larger breaking length. 9.4 Special determination
Open the tester: stretch the sample until it breaks. Record the breaking strength (unit: N), breaking elongation (unit: m/s) or breaking elongation (unit: %). If necessary, record the direction of breaking and the elongation of the breaking fracture. Test at least five pieces in each direction. If the asymmetric slip of the specimen at the joint is greater than 2 mm, the test result shall be discarded. 9.4.2 Joint new type
If the specimen breaks within 5 mT from the joint, it shall be regarded as a clamp fracture. When the five tests are completed If the value of the fracture is greater than the minimum "normal value", it should be retained. If it is less than the minimum "positive value", it should be discarded and another test should be conducted to obtain five "normal values". If all the test results are fracture, and the five "no
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.