Some standard content:
ICS 29.080.10www.bzxz.net
K48
Mechanical Industry Standard of the People's Republic of China
JB/T 4307--2004
Replaces JB/T4307—1986
Insulator Cement mortar for insulators
Cement mortar for insulators released on 2004-02-10
Implemented on 2004-06-01
Foreword released by the National Development and Reform Commission of the People's Republic of China
1 Scope
2 Normative reference documents,
3 Terms and definitions.
4 Classification of cement adhesives
5 Technical requirements for cement adhesives.
6 Test methods
6.1 General provisions.
6.2 Flexural strength test.
6.3 Compressive strength test
6.4 Pressure steam expansion rate test
6.5 Test report.
7 Inspection Rules,
Country
Appendix A (Informative Appendix) Reference Technical Requirements for Cement Adhesives, A. Introduction....
A.2 Technical Requirements..
A.3 Test Methods..
Times
Appendix B (Informative Appendix) Technical Requirements for Cement Adhesive Raw Materials..Appendix (Informative Appendix) and Introduction to standards C.1 related to cement binder raw materials.
C.2 List of relevant standards for cement adhesive raw materials, Figure 1 Pressure steam expansion rate test specimen and plug. Table 1 Classification of cement adhesives,
Table 2 Technical performance indicators of cement adhesives. .Table A.1 Reference technical performance indicators of cement adhesives Table B.1 Reference technical indicators of cement raw materials ..Table B.2 Technical indicators of quartz sand.
JB/T4307—2004
.
12
Foreword
This standard replaces JB/T4307—1986 "Technical Conditions for Cement Adhesives for Insulator Adhesion 》. JB/T4307--2004
Compared with JB/T1307-1986, the main changes of this standard are as follows: According to GB/T1.1-2000. "Standardization Work Guidelines Part 1: Standard Structure and Writing Rules 》Preparation: Only the three main technical requirements of cement adhesives (flexural strength, compressive strength and autoclave expansion rate) are listed in the normative technical elements, and other technical requirements are only listed in the informative appendix as reference indicators. : Delete the "elastic modulus" and "tensile strength" technical indicators; - The scope of application has added ferroaluminate cement and sulfoaluminate cement cementitious materials. Appendix A, Appendix B and Appendix C of this standard are the information. Sexual addendum. This standard was proposed by the China Machinery Industry Federation: This standard is under the jurisdiction of the National Insulator Standardization Technical Committee. This standard was drafted by: Xi'an Electric Porcelain Research Institute. The main drafter of this standard: Zhou Faxiang.
The previous versions of the standards replaced by this standard are: -JB/T4307—1986.
1 scope
Cement adhesive for insulator bonding
This standard stipulates The definition, classification, technical requirements, test methods and inspection rules of cement adhesives are provided. JB/T 4307—2004
This standard applies to cement adhesives for porcelain or glass insulators using Portland cement, ferroaluminate cement and sulphoaluminate cement as cementing materials.
2 Normative reference documents
The clauses in the following documents become the clauses of this standard through reference in this standard. For dated reference documents, all subsequent amendments (excluding corrigenda) or revisions do not apply to this standard. However, parties to an agreement based on this standard are encouraged to study whether the latest versions of these documents can be used. . For undated referenced documents, the latest edition applies to this standard. GB/T177-1985 Cement mortar strength test method GB/T750-1992 Cement pressure steam stability test method GB/T2900.8-1995 Electrical terminology insulator GB/T4131-1997 Cement nomenclature, definition and terminology JB/T5896—— 1991 Commonly used insulator terms JC/T724—1982 (1996) Cement physical testing instrument electric flexural testing machine JC/T725-1982 (1996) Cement physical testing instrument compression fixture JCT726—1997 cement mortar test mold
3 Terms and Definitions
The terms and definitions established in GB/T2900.8, GB/T4131 and JB/T5896 and the following terms and definitions apply to this standard. 3.1 | | tt | A substance that hardens to permanently connect the porcelain or glass parts of an insulator to metal accessories, as well as between porcelain parts or glass parts.
Note: In order to improve the performance of cement adhesive, admixtures can be added. 3.2 | After steam treatment for 3 hours, the deformation of the sample reflects the hydration expansion of periclase. 4 Cement adhesive classification
Cement adhesives are divided into three categories: ordinary adhesives (I), medium-strength adhesives (II) and release-strength adhesives (1II). See the table for specific regulations! .
JB/T 4307--2004
Class
1
Specification
Category Name
Titon Cement Adhesive|| tt||Table 1 Classification of cement adhesives
Composition and process characteristics
Generally, Portland cement, ordinary Portland cement, and slag Portland cement with a strength level of 42.5 are used as cementing materials .
-Generally, Portland cement with strength grade 42.5, 42.5R and 425 medium-strength cement adhesive
high-strength cement adhesive
5 cement adhesive technology Requirements
The technical performance of cement adhesive should meet the requirements of Table 2, and the fast-hardening sulfoaluminate cement is the cementing material. The water-cement ratio, lime-sand ratio, and curing conditions require strict control, and machinery should be used to prepare the adhesive. Generally, Portland cement with strength grade 52.5, 52.5R and above, fast-hardening Portland cement with grade 425, fast-hardening sulfoaluminate and fast-hardening ferroaluminate cement with grade 525 and above, or The cement specially produced and selected for grinding with clinker is used as glue material, and cement admixtures are generally used. The water-cement ratio, lime-sand ratio, adhesive preparation and maintenance all require strict control.
Note: Appendix A gives the technical requirements for some items of cement adhesives. The test items in Appendix A can be selected as test items for type tests or other tests according to the requirements of the insulator to ensure that the insulator passes the relevant tests. The strength properties of the cement should be the test results of the sample after 11 days of molding, the test result value of the sample when the age exceeds 11 days, the compressive strength of medium-strength cement cement (category 11) and high-strength cement cement (category I) It should be 10% higher than specified in Table 2. The raw materials of cement adhesive should be inspected when they are imported into Guangdong, and users can conduct necessary factory inspections on the raw materials. The technical requirements for cement adhesive raw materials can be found in Appendix B. Note: Appendix C gives some standards related to raw materials. Table 2 Technical performance indicators of cement adhesive
sequence
number
2
3
item
flexural strength MPa is not low The compressive strength MPa of
is not less than
pressure steam expansion rate
is not greater than
mesh
1
7.0||tt ||54.0
0.10%
category
I
8.5
64.0
0.10%
different||tt ||10.5
83.5
0.10%
! The "pressure steam expansion rate" is only applicable to cement adhesives for disc-shaped suspended insulators, and cement adhesives for other insulators can be used as reference items. 6 Test methods
6.1 General provisions
6.1.1·The raw material composition and process method of the cement adhesive sample should be as consistent as possible with the actual production. 6.1.2 The surface of the sample should be smooth and smooth, with no Streaks, cracks and large holes (aperture greater than 5mm), corners should be intact. 6.1.3 The environmental conditions for cement adhesive testing should comply with GB/T177-1985 3.1. Requirements for temperature and humidity.
6.2 Flexural strength test
6.2.1 Samples
The number of specimens for the flexural strength test is 3. The sample is a 40mm × 40mm × 160mm cuboid, and the sample should be formed using a cement mortar trial mold that meets the requirements of JC/T726-1997. The specimens should be formed in accordance with GB/T177-1985 using a vibrating table vibration forming or manual tamping method. 6.2.2 Test instruments
2
JB/r 4307—2004
Flexural strength test can use an electric flexural testing machine that meets the requirements of JC/T724--1982 (1996) , other testing machines whose performance meets the requirements can also be used. The anti-bending clamp should comply with the requirements of 2.5~2.9 in JC Jin 724-1982 (1996). 6.2.3 Test procedure
Before the test, the water, sand and other debris on the surface of the sample should be wiped off, and the debris adhered to the surface of the support cylinder and loading cylinder on the fixture should be removed. The sample should be placed in the clamp. The side surface during molding should be in contact with the cylinder. When testing with a lever-type bending testing machine, before placing the sample, the lever should be in a balanced state without load. After placing the specimen, adjust the clamp so that the lever is as close to the equilibrium position as possible when the specimen breaks. The test load should be increased at a rate of (50 ± 5) N/s until the specimen breaks and fails. , Note: The broken block after this test. It can be used for pressure test and abnormal pore number inspection. 6.2.4 Calculation
The flexural strength is calculated according to formula (1):
1.5F,L
Rr
3
where: | |tt||Rr - flexural strength, unit is MPa:
- distance between supporting cylinders. The unit is mm: F
b
The load applied to the middle part of the cuboid when it is broken, the unit is N: The side length of the square section of a cuboid, the unit is mm. The calculation of flexural strength is accurate to 0.1MPa.
(
The flexural strength test results are calculated based on the arithmetic mean of 3 specimens. When a value exceeds 10% of the average, the value should be divided separately and the remaining two values The average value is used as the result of the flexural test. If two values ??exceed 10% of the average value, the test should be repeated. 6.3 Compressive strength test
6.3.1 Sample
The sample can be. For broken blocks that meet the requirements after the flexural test, the specimen should have a compressive area of ??at least 40mm × 62.5mm. The compressive strength test should be carried out as soon as possible after the flexural test. The number of specimens is 6.3.2 Test equipment | |tt||The specification of the pressure testing machine is 300kN or 600kN, and the error should not exceed 2%. The compressive strength test fixture should comply with the requirements of JC/T725-1982 (1996) 6.3.3 Test procedure
The broken block after the flexural test is placed on the pressure plate of the pressure test fixture. Use the fixture to ensure that the pressure area of ??the sample is 40mm × 62.5mm. Sand or debris between the pressure surface of the sample and the pressure plate should be removed. During the test, the surface of the sample when it is formed is used as the pressure-bearing surface. The pressure testing machine should apply the load at a speed of (5 ± 0.5) kN/s until the sample is destroyed. The pressurization speed should be strictly controlled when the sample is damaged. After this test, the unpressurized part of the sample outside the pressure plate can be reserved as a water absorption test sample. 6.3.4 Calculation
The compressive strength is calculated according to formula (2):
R
In the formula:
R. Compressive strength, unit is MPa;
is the maximum load at failure, unit is N: F
is the compressed part Area, unit is mm2.
A
Compressive strength calculation is accurate to 0.1MPa:
F
A
(2)||tt| |Among the six compressive strength test results, the largest and smallest values ??should be eliminated, and the arithmetic mean of the remaining four values ??should be used as the compression test 3
JB/T4307-2004
When the test value is less than 6, the arithmetic mean of all data shall be taken as the test result. When the number of samples is less than 4, the post-sample test shall be repeated
6.4 Pressure steam expansion rate test| | tt | However, there are round holes at both ends for placing the specimen measuring heads. The position of the round holes should ensure that the two heads are on the center line of the specimen. The structural dimensions of the specimen and the stainless steel measuring heads should comply with the requirements of Figure 1. 3. The test mold and stainless steel measuring head can also be formed according to the requirements of GB/T750-1992. They should be formed by vibrating table or manually compacted, and then removed after curing for 24 hours.
(Martial style:
R2.3
e
4
18
(head)
6.4. 2 Test instruments and equipment
6.4.2.1 Autoclave
Figure 1 Pressure steam expansion rate test sample and head
is a high-pressure water vapor heating vessel equipped with a pressure (temperature ) automatic controller, air release valve and safety valve. It can raise the steam pressure in the sign to the gauge pressure (2.0±0.05) MPa (equivalent to 215.7℃±1.3℃) within 45min~75min and maintain it for more than 3h. It can reduce the pressure to below 0.1MPa within 90min after stopping heating. . 6.4.2.2 The effective volume of the boiling box
is approximately 410mm × 240mm × 310mm. The grate plate structure should not affect the test results. The distance between the grate plate and the heater should be greater than 50mm. The inner layer of the box is made of metal material that is not easy to rust. It can heat the test water in the box from room temperature to boiling within (30 ± 5) minutes, and can maintain the boiling state for more than 4 hours. There is no need to add water during the entire test process. . 6.4.2.3 Length measuring instrument
Any of the following length measuring instruments may be used. Shrinkage and expansion meter: It consists of a measuring frame, a standard push rod and a support. The standard rod length is (175 ± 0.02) mm. Dial indicator for measurement, the minimum scale value is 0.01mm.
-length ratio meter: according to GB/T750-1992. 6.4.3 Test procedure
After the sample is demolded, measure the initial length on the length measuring instrument (use the standard push rod to calibrate the zero position). The sample whose initial length has been measured is placed in the boiling box, immersed in water and boiled. Boil continuously for 4 hours from the time the water boils and then stop. Add cold water to the pot and cool it to room temperature after 15 minutes. After another 15 minutes, take out the sample and wipe it dry. , measure its boiled length on a length measuring instrument. The sample that has been boiled and measured in length is placed on the inner holder of the pressure steaming stick, and a sufficient amount of distilled water is poured into the kettle (water accounts for 7%~4 of the kettle volume
JR/T 4307—2004||tt ||10%, but must not come into contact with the sample), the release valve should be opened in the early stage of heating to allow the air in the sign to be discharged. After 1h~-1.4h, the internal pressure reaches 2.0MPa, keep it at 2.0±0.05MPa for 3h, and stop heating. After the pressure drops below 0.1MPa, open the air valve slightly to discharge the residual steam in the stick, open the pressure steaming stick, take out the sample and place it in hot water above 90°C, then pour cold water evenly into it, and let the water temperature rise within 10 to 15 minutes. Lower to room temperature, keep for another 15 minutes, take out the sample and dry it, measure the length after autoclaving on a length measuring instrument. If the sample has abnormal phenomena such as bending or cracking, it should be recorded at the same time.
6.4.4 Calculation
Calculate the pressure steam expansion rate according to formula (3)
S.
where:
Sp——pressure steam expansion Rate, %:
L. —The length after autoclaving, in mm
L, the initial length in mm:
Lp L
L
100%
— —The effective length of the adhesive sample is 140mm (250mm when the sample is stipulated in GB/T750-1992). L
The boiling expansion rate is calculated according to formula (4)
where:
St-boiling expansion rate, %;
Le——after boiling Length in mm. The autoclaved expansion ratio calculation is accurate to 0.01%.
s =Lr
L
Calculate the arithmetic mean value measured on the sample. When one value exceeds 15% of the average value, this value should be eliminated, and the average of the remaining two values ??will be used as the test result of the pressure steam expansion rate. If there are two values If the value exceeds 15% of the average value, the test should be repeated.
Note: The boiling expansion rate is used to observe the effect of free calcium oxide in cement on the stability. The expansion rate value is included in the pressure steam expansion rate. 6.5 Test report
The test report should include the following contents:
a) Name of adhesive, date of sample preparation and production unit: b) Test items:
c) Preparation of sample ( Formula, maintenance), shape, size and quantity: d) Sample processing conditions and test conditions:
e) Main test instruments and equipment;
f) Test data and data processing: ||tt| |g) Evaluation of test results:
h) Test unit, test personnel and test date. 7 Inspection Rules
7.1 The inspection of cement adhesive for insulator binding is divided into type test, periodic test and batch test. When requested by the party, the insulator manufacturer shall provide the test report of the cement adhesive. 7.2 The type test is only conducted once for a new cement adhesive or glue binding process. It should be repeated if its formula composition or glue binding technology changes in the future.
All types of cement adhesives should undergo type tests for the following items. If any of the performance in the test fails, the type test is deemed to have failed. a) Flexural strength test (see Tables 2 and 6.2): ??5
JB/T4307-2004
b) Compressive strength test (see Tables 2 and 6.3): c) Autoclave expansion rate Tests (see Tables 2 and 6.4) (only for disc-shaped suspension insulators), 7.3 periodic tests are divided into monthly periodic tests and annual periodic tests, which should be conducted once a month and once a year as specified. The test methods and technical indicators of periodic tests and type tests are the same. If any one of the test items is unqualified, the periodic test will be considered unqualified. The monthly test items are as follows:
Flexural strength test:
Compressive strength test.
The annual test items are as follows;
Autoclaved expansion rate test (only for disc-shaped suspension insulators) When the type of cement used in the adhesive is the same as that of the manufacturer, but the batch of cement entering the factory is changed, Batch testing of cement adhesives should be carried out. 7.4
The test methods and technical indicators of batch testing and type testing are the same. If any of the test items fails. The batch test is deemed to be unqualified.
The batch test items are as follows:
Flexural strength test:
-Compressive strength test.
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.