Some standard content:
National Standard of the People's Republic of China
Three-strand polyester multifilament ropes
Three-strand polyester multifilament ropes This standard refers to the international standard IS01141-1975 "Three-strand polyester multifilament ropes" subject content and scope of application
This standard specifies the main characteristics and markings of three-strand polyester multifilament ropes. GB/T11787-89
This standard is applicable to ropes with a linear density of 11.8 to 6990 ktex and a reference diameter of 4 to 96 mm. 2 Reference standards
GB3291
GB4146
GB6530
3 Marking
Textile terminology (general part of textile materials and textile products) Textile terminology (chemical fiber part)
Sampling and humidity conditioning for rope testing
The rope should have the following markings:
"rope";
-reference diameter (equivalent to the approximate diameter of the rope measured at zero tension in millimeters);-variety (name of the constituent material);
Number of strands;
Rope type;
-reference this standard.
Marking example:
-The marking of a three-strand polyester multifilament rope with a reference diameter of 30 mm (linear density of 682 ktex) is as follows: Rope, 30, polyester, 3 strands, Type A, GB/T11787 Rope type
Ropes are divided into three types:
Type A three-strand twisted rope without rope core;
Type B four-strand twisted rope with rope core;
Type C eight-strand braided rope without rope core.
Three-strand polyester multifilament rope belongs to Type A.
Three-strand rope (type A) morphology
Approved by the State Administration of Technical Supervision on November 6, 1989 and implemented on July 1, 1990
5 Characteristics and allowable deviations
5.1 Main characteristics
GB/T11787-89
The main characteristics of three-strand polyester multifilament ropes shall be as shown in the following table. Main characteristics of three-strand polyester multifilament ropes
Reference diameter
Nominal value
Line density
Note: Other grades shall be agreed upon by the buyer and seller. 92
Allowable deviation
Reference tension for determination of linear density
Nominal value
Allowable deviation
Minimum breaking strength
Superior quality
12 000
19 000
32 900
38 400
70 700
104 000
123000
GB/T11787-89
The determination of linear density and breaking strength of ropes may be carried out according to the procedures described in Appendix A (supplementary) or Appendix B (reference). 5.2 Other characteristics
Other characteristics involving rope constituent materials, structure and span shall be in accordance with Appendix C (reference), or may be agreed upon by the buyer and seller according to the needs of the samples provided.
The rope shall be made of a blue yarn or flat wire that is easily identifiable and placed inside the rope to indicate that the material, properties and origin of the polyester rope comply with this standard. The mark shall remain identifiable despite the infiltration and contamination of dust or liquid during use. 6.1 Rope reference diameter <12mm:
A blue yarn or flat wire shall be woven into one strand. 6.2 Rope reference diameter ≥12mm:
A blue flat wire at least 3mm wide, printed with the reference to this standard and the manufacturer's mark, shall be woven into one strand. The maximum distance between two consecutive marks is 1m. 7 Labels
Each roll of rope shall be accompanied by a label indicating the following: Constituent materials;
-Manufacturer's mark;
-Reference diameter;
-Delivery length;
Reference to this standard and its grade.
8 Packaging and delivery length
8.1 The rope should be neatly wound and firmly tied with chemical fiber ropes. The packaging of the rope should be suitable for storage and transportation without damage. When the rope is delivered by gross weight, the mass of the packaging material shall not exceed 1.5% of the gross weight of the rope. 8.2 Delivery length
Unless otherwise specified, the delivery length shall be the length measured under zero tension. The normal delivery length is 100m, 200m or 220m. The allowable deviation of the delivery length of the rope is:
When the reference diameter of the rope is <14mm, it is ±5%;
When the reference diameter of the rope is >14mm, it is ±3%.
The condition is that the total weight of the rope corresponding to the delivery length is not less than the product of the minimum linear density and the theoretical delivery length. Other lengths can be agreed upon by the buyer and seller according to special requirements. A1 Principle
GB/T11787-89
Appendix, A
Test method for linear density and breaking strength of ropes (supplement)
Linear density is calculated by dividing the total weight of the specimen by its length under reference tension. A1.2 Breaking strength is determined when the tension increases to the breaking point. A2 Equipment
A2.1 Balance: with an appropriate range, the accuracy of measuring mass should be 1%. A2.2 Tensile strength testing machine: with an appropriate range, its moving parts can be pulled at a constant speed, and the accuracy of measuring breaking strength is 1%. The following different types of clamps can be used:
Wedge clamp;
Through-eye cable bitt;
Drum-disc clamp.
A3 Sampling
The sampling before the test shall be carried out in accordance with the requirements specified in GB6530. In order to obtain accurate measurement results, the two ends of the sample shall be tied before the sample is removed from the rope package, and then cut as close to the tied end as possible.
If there is no other agreement between the relevant parties, the sample shall be of sufficient length after being installed on the testing machine. According to the provisions of A5 (Figure A1, Figure A2 and Figure A3), the effective length shall at least reach the value shown in Table A1. Table A1 Effective length
Rope type
Reference diameter of chemical fiber rope ≤10mmReference diameter of chemical fiber rope>10mm
Natural fiber rope
A4 Initial measurement
Testing machine type
Various types
Wedge-shaped clamp or drum-type clamp
Other types
Minimum effective length required for the test
Put a specimen of appropriate length flat on a plane without tension, straighten it, and measure its length, which is expressed in Lo (unit: m) with an accuracy of 1%.
Mark two points symmetrically to the midpoint of the specimen, at least 0.5m apart. The distance between the two points is expressed in. Determine the mass of the specimen, which is expressed in m (unit: 8) with an accuracy of 0.05%. A5 Installation of the specimen on the testing machine
A5.1 Depending on the type of clamp used (wedge-type clamp, drum-type clamp or eye-through cable bollard), fix the specimen between the two clamps. The effective length L of the specimen must be consistent with that specified in Table A1. The effective length L should be measured under zero tension conditions. For the three main types of clamps, the specimen needs to be kept straight. When testing according to the method shown in Figure A1 and Figure A3 of GB/T11787-89, care should be taken not to untie or unbundle the specimen before the test to cause it to become loose. Figure A1
Specimen installed between wedge-shaped clamps
Note: The limit mark of the specimen\r\ should be aligned with the jaws of the clamp. Figure A2 Eyelet splicing of the sample between two cable studs
Note: ① The limit mark \" should be 150mm away from the end of the splicing. ② When using the eyelet method cable stud clamp test, it should be ensured that there is a length of 250-300mm inside the eye before splicing. For chemical fiber ropes, the splicing should be arranged into a cone.
Figure A3 Sample mounted on a drum (drum type clamp) Note: The limit mark *" should be at the point where the rope leaves the drum type clamp. A5.2 The mark "" indicates a test section where the sample is mounted on the testing machine. When conducting a breaking test, the rope is usually required to break in this part.
A6 New distance between marks
Subject the sample to the reference tension used to determine the linear density, and measure the new distance between the two marks made on the sample during the initial measurement (see Figure A2). This distance is expressed as l2. For chemical fiber rope samples with a reference diameter of ≤10mm (minimum effective length of 400mm), the l2 value can be measured as follows: first, lay the rope sample flat on a plane, make initial marks according to the provisions of A4, and the distance between them is not less than 0.50m. Then, apply the specified tension by hanging a heavy hammer on a pulley, and the l value can be measured. A7 Determination of breaking strength
Increase the tension through the action of the moving parts of the testing machine until the rope breaks. A7.1 Test speed
The pulling rate of the moving part of the testing machine should be constant. When the rate is expressed in millimeters per minute, its value should be within 6~95
GB/T1178789
10% of the effective length of the sample. For all chemical fiber ropes, the pulling rate of the moving part shall not exceed 250mm/min. A7.2 Breakage
In order to determine whether the test results represent the true strength of the rope, pay attention to the breaking strength and the position of the sample break. The damage to the sample caused by the clamp will seriously affect the test results. Therefore, before applying the load, install the sample according to the method of A5 and mark the sample. The breakage should occur between the two marks of the sample. If the breakage point occurs outside the mark and the breaking strength is lower than the specified value, but the recorded load is not less than 90% of the specified breaking strength, then the tensile strength of the sample can also be regarded as consistent with the regulations. Otherwise, the test is invalid and the test should be repeated.
The breaking strength value reported as the test result must be the value actually recorded during the test. A8 Expression of test results
A8.1 Linear density (net mass per meter)
The linear density (i.e. net mass per meter) p, can be obtained by formula (A1): P,
where: m - mass of the sample, g;
L length of the sample under the reference tension, m.
L can be calculated by formula (A2).
Li =hx Lo
where: lo - initial distance between marks measured according to A4; 12 - distance between marks under the reference tension measured according to A6; L. - initial total length of the sample measured according to A4. The linear density is the average value of all the samples used for the test, and the result is in grams per meter or kilotex. A8.2 Breaking strength
(A1)
(A2)
Express each test result in decaNewtons (daN), take the lowest value instead of the average value, and indicate whether the break occurs between the marks. A9: Test report
The test report shall include the following parts: test results;
reference to this standard;
detailed test conditions (type of testing machine used, test speed), if the method described in Appendix B (reference) is used, it should be stated.
values used in the calculation results;
any operating details not included in this standard, and factors that may affect the test results. Appendix B
Special procedures for determining high breaking strength
(reference)
B1 When the breaking strength of a three-ply rope made of yarns of the same material and the same linear density is greater than 30,000 daN, the following method may be used to convert the strength of the three-ply rope by measuring the breaking strength of the yarns in the rope, but the rope must meet the specified requirements in all other aspects as a prerequisite.
B2 In order to obtain the yarns required for the test, a sufficient length of rope shall be withdrawn and any rotation of the individual rope components (such as yarns, strands) around their own 96
GB/T11787-89
axial direction shall be avoided. The number of yarns tested is equal to half the value of the reference diameter (mm) of the rope. For a three-ply rope, 15 yarns shall be tested, of which 3 shall be drawn from the core.
B3 The selected rope yarn should be of sufficient length to provide a minimum effective length Lu of 250mm. The specimens are installed on the testing machine in sequence. During this process, care must be taken to avoid unpicking the rope yarn before the test. B4
B5 In the rope yarn breaking test, the traction rate of the moving part of the strength testing machine is measured in millimeters per minute, and its value is equal to the length of the specimen in millimeters. The breaking strength of the rope (F.) can be calculated and determined based on the average strength measured by the extracted rope yarns. The formula is as follows: F=F,×n×r
Where: F,-average rope yarn strength, daN;
-total number of rope yarns in the rope;
-calculation coefficient (see Table B1).
Table B1 Calculation coefficients for polyester ropes
Reference diameter, mmWww.bzxZ.net
Calculation coefficients
(B1)
B6 If the breaking strength of the rope is obtained by calculation, it should be stated in the test report, commercial documents and when negotiating with the buyer. Appendix C
Material, structure, wheel gauge and treatment of three-strand polyester multifilament ropes (reference)
C1 The polyester fiber density of the rope is about 1.38kg/dm, and the content of titanium dioxide in the fiber is not more than 0.05%. The rope should be made of new raw materials.
C2 The three-strand rope belongs to type A. Unless otherwise specified, its structure is characterized by no rope core, and the rope strands are twisted in the "z" direction. These rope strands themselves are "S". The maximum lay length of the rope under the reference tension (the same tension as that used for determining the linear density) is 3.5 times the rope diameter. C3 The rope and the rope strands should be continuous without picking up. The number of yarns in each strand of the rope shall be the same. When the strand contains a strand core, the number of strand core multifilaments in each strand of the rope shall also be the same. For ropes with a reference diameter of 36 and above, a slight difference in the number of yarns in each strand is allowed, and the difference is ±2.5% of the average number of yarns in one strand. C4 ropes should ensure structural stability. Usually supplied in a natural state, that is, without molten or coated. At the request of the buyer, the rope can be coated or impregnated to obtain special properties. The characteristics of the coating or impregnation material shall be stated by the manufacturer, and the treatment of the rope shall not reduce the breaking strength of the rope. Unless agreed by both parties, the increased mass of the rope after coating or impregnation shall not exceed 5% of the mass of the rope in its natural state.
Additional remarks:
GB/T11787-89
This standard is proposed by the Ministry of Textile Industry of the People's Republic of China. This standard is under the jurisdiction of the Standardization Research Institute of the Ministry of Textile Industry. This standard was drafted by China Textile University, with the cooperation of Shanghai Textile Standard and Metrology Institute, Shanghai Wire and Belt Company, and Shanghai Cable Factory. The main drafters of this standard are Li Yongchun, Hui Yinqiu, and Zhou Xiangshu.
Values used in the calculation results;
Any operating details not included in this standard, and factors that may affect the test results. Appendix B
Special procedures for determining high breaking strength
(reference)
B1 If the breaking strength of a three-ply rope made of yarns of the same material and the same linear density is greater than 30,000 daN, the following method can be used to convert the strength of the three-ply rope by measuring the breaking strength of the yarns in the rope, but the rope must meet the specified requirements in all other aspects as a prerequisite.
B2 In order to obtain the rope yarn required for the test, it is necessary to withdraw a sufficient length of rope and avoid any rotation of the individual rope components (such as rope yarns, rope strands) around their own axis. The number of tested yarns is equal to half the value of the reference diameter (mm) of the rope. For three-strand ropes, 15 yarns are tested, of which 3 should be drawn from the core.
B3 The selected yarns should be of sufficient length to provide a minimum effective length Lu of 250 mm. The samples are installed on the testing machine in sequence. During this process, care must be taken to avoid the yarns from being unpicked before the test. B4
B5 In the yarn breaking test, the traction rate of the moving part of the strength testing machine is measured in millimeters per minute, and its value is equal to the length of the sample in millimeters. The breaking strength of the rope (F.) can be calculated based on the average strength measured by the extracted yarns. The formula is as follows: F=F,×n×r
Where: F,-average yarn strength, daN;
-total number of yarns in the rope;
-calculation coefficient (see Table B1).
Table B1 Calculation coefficients for polyester ropes
Reference diameter, mm
Calculation coefficients
(B1)
B6 If the breaking strength of the rope is obtained by calculation, it should be stated in the test report, commercial documents and when negotiating with the buyer. Appendix C
Material, structure, wheel gauge and treatment of three-strand polyester multifilament ropes (reference)
C1 The polyester fiber density of the rope is about 1.38kg/dm, and the content of titanium dioxide in the fiber is not more than 0.05%. The rope should be made of new raw materials.
C2 The three-strand rope belongs to type A. Unless otherwise specified, its structure is characterized by no rope core, and the rope strands are twisted in the "z" direction. These rope strands themselves are "S". The maximum lay length of the rope under the reference tension (the same tension as that used for determining the linear density) is 3.5 times the rope diameter. C3 The rope and the rope strands should be continuous without picking up. The number of yarns in each strand of the rope shall be the same. When the strand contains a strand core, the number of strand core multifilaments in each strand of the rope shall also be the same. For ropes with a reference diameter of 36 and above, a slight difference in the number of yarns in each strand is allowed, and the difference is ±2.5% of the average number of yarns in one strand. C4 ropes should ensure structural stability. Usually supplied in a natural state, that is, without molten or coated. At the request of the buyer, the rope can be coated or impregnated to obtain special properties. The characteristics of the coating or impregnation material shall be stated by the manufacturer, and the treatment of the rope shall not reduce the breaking strength of the rope. Unless agreed by both parties, the increased mass of the rope after coating or impregnation shall not exceed 5% of the mass of the rope in its natural state.
Additional remarks:
GB/T11787-89
This standard is proposed by the Ministry of Textile Industry of the People's Republic of China. This standard is under the jurisdiction of the Standardization Research Institute of the Ministry of Textile Industry. This standard was drafted by China Textile University, with the cooperation of Shanghai Textile Standard and Metrology Institute, Shanghai Wire and Belt Company, and Shanghai Cable Factory. The main drafters of this standard are Li Yongchun, Hui Yinqiu, and Zhou Xiangshu.
Values used in the calculation results;
Any operating details not included in this standard, and factors that may affect the test results. Appendix B
Special procedures for determining high breaking strength
(reference)
B1 If the breaking strength of a three-ply rope made of yarns of the same material and the same linear density is greater than 30,000 daN, the following method can be used to convert the strength of the three-ply rope by measuring the breaking strength of the yarns in the rope, but the rope must meet the specified requirements in all other aspects as a prerequisite.
B2 In order to obtain the rope yarn required for the test, it is necessary to withdraw a sufficient length of rope and avoid any rotation of the individual rope components (such as rope yarns, rope strands) around their own axis. The number of tested yarns is equal to half the value of the reference diameter (mm) of the rope. For three-strand ropes, 15 yarns are tested, of which 3 should be drawn from the core.
B3 The selected yarns should be of sufficient length to provide a minimum effective length Lu of 250 mm. The samples are installed on the testing machine in sequence. During this process, care must be taken to avoid the yarns from being unpicked before the test. B4
B5 In the yarn breaking test, the traction rate of the moving part of the strength testing machine is measured in millimeters per minute, and its value is equal to the length of the sample in millimeters. The breaking strength of the rope (F.) can be calculated based on the average strength measured by the extracted yarns. The formula is as follows: F=F,×n×r
Where: F,-average yarn strength, daN;
-total number of yarns in the rope;
-calculation coefficient (see Table B1).
Table B1 Calculation coefficients for polyester ropes
Reference diameter, mm
Calculation coefficients
(B1)
B6 If the breaking strength of the rope is obtained by calculation, it should be stated in the test report, commercial documents and when negotiating with the buyer. Appendix C
Material, structure, wheel gauge and treatment of three-strand polyester multifilament ropes (reference)
C1 The polyester fiber density of the rope is about 1.38kg/dm, and the content of titanium dioxide in the fiber is not more than 0.05%. The rope should be made of new raw materials.
C2 The three-strand rope belongs to type A. Unless otherwise specified, its structure is characterized by no rope core, and the rope strands are twisted in the "z" direction. These rope strands themselves are "S". The maximum lay length of the rope under the reference tension (the same tension as that used for determining the linear density) is 3.5 times the rope diameter. C3 The rope and the rope strands should be continuous without picking up. The number of yarns in each strand of the rope shall be the same. When the strand contains a strand core, the number of strand core multifilaments in each strand of the rope shall also be the same. For ropes with a reference diameter of 36 and above, a slight difference in the number of yarns in each strand is allowed, and the difference is ±2.5% of the average number of yarns in one strand. C4 ropes should ensure structural stability. Usually supplied in a natural state, that is, without molten or coated. At the request of the buyer, the rope can be coated or impregnated to obtain special properties. The characteristics of the coating or impregnation material shall be stated by the manufacturer, and the treatment of the rope shall not reduce the breaking strength of the rope. Unless agreed by both parties, the increased mass of the rope after coating or impregnation shall not exceed 5% of the mass of the rope in its natural state.
Additional remarks:
GB/T11787-89
This standard is proposed by the Ministry of Textile Industry of the People's Republic of China. This standard is under the jurisdiction of the Standardization Research Institute of the Ministry of Textile Industry. This standard was drafted by China Textile University, with the cooperation of Shanghai Textile Standard and Metrology Institute, Shanghai Wire and Belt Company, and Shanghai Cable Factory. The main drafters of this standard are Li Yongchun, Hui Yinqiu, and Zhou Xiangshu.
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