GB/T 1695-2005Rubber, vulcanized - Determination of electrical breakdown strength and voltage resistant at commercial power frequency (English PDF)

Foreword

This standard corresponds to the American Military Materials and Testing Association

standard ASTM D149-97a "Standard test method for dielectric breakdown voltage and

dielectric strength of solid electrical insulating materials at commercial power

frequencies". The degree of consistency with ASTM D149-97a is non-equivalent.

This standard replaces GB/T 1695-1981 (1989) "Vulcanized rubber - Test method for

industrial frequency puncture voltage and dielectric strength".

This standard revises GB/T 1695-1981(1989) according to ASTM D149-97a. The main

technical differences between this standard and ASTM D149-97a are as follows.

- ASTM D149-97a has a wide range of applications. It is aimed at the determination

of power frequency breakdown voltage and dielectric strength of solid insulating

materials. This standard is basically consistent with ASTM D149-97a in terms of

technical contents such as electrode materials, electrode dimensions, test device.

- Based on the verification test, the provisions of taking the median in GB/T 1695-

1981(1989) are retained, which is different from the provisions of taking the mean

in ASTM D149-97a.

- This standard is only for rubber materials; it only specifies two types of electrodes

and two boosting methods.

Compared with GB/T 1695-1981 (1989), the main changes in this standard are as

follows.

- ADD a reference to this standard;

- ADD a warning to this standard;

- ADD Chapter 2 Normative references to this standard;

- ADD Chapter 3 Terms and definitions to this standard;

- ADD a plate electrode in 4.5.2 to this standard;

- ADD the requirements for specimen thickness measurement devices in 4.6 of this

standard.

This standard was proposed by the China Petroleum and Chemical Industry Association.

This standard shall be under the jurisdiction of the Rubber Physical and Chemical Test

Methods Technical Committee of the National Rubber Standardization Committee

(SAC/TC 35/SC 2).

Rubber, vulcanized - Determination of electrical breakdown

strength and voltage resistant at commercial power

frequency

Warning - Personnel using this standard shall have practical experience in formal

laboratory work. This standard does not point out all possible safety issues. Users

are responsible for taking appropriate safety and health measures and ensuring

compliance with the conditions stipulated in relevant national laws and regulations.

1 Scope

This standard applies to the application of AC voltage to the specimen by continuous

uniform or step-by-step voltage increase until breakdown, measuring the breakdown

voltage value, calculating the breakdown strength of the specimen; using the method of

rapid voltage increase, the voltage is increased to a specified value; the specimen is kept

for a certain period of time without breakdown; this specified value is determined as

the withstand voltage value of the specimen.

2 Normative references

The provisions in following documents become the provisions of this Standard through

reference in this Standard. For the dated references, the subsequent amendments

(excluding corrections) or revisions do not apply to this Standard; however, parties who

reach an agreement based on this Standard are encouraged to study if the latest versions

of these documents are applicable. For undated references, the latest edition of the

referenced document applies.

GB/T 2941 Rubber-Standard temperatures, humidities and times for the

conditioning environmental and testing of test pieces (GB/T 2941-1991, eqv ISO

471.1983)

GB/T 5723 Rubber, vulcanized or thermoplastic - Determination of dimensions of

test pieces and products for test purposes (GB/T 5723-1993, eqv ISO 4648.1991)

GB/T 9865.1 Rubber, vulcanized or thermoplastic - Preparation of samples and test

pieces - Part 1.Physical tests (GB/T 9865.1-1996, idt ISO 4661-1.1993)

3 Terms and definitions

The following terms and definitions apply to this standard.

9 Test results

The breakdown voltage intensity E (kV/mm) is calculated according to the following

formula.

Where.

U - Breakdown voltage, in kilovolt (kV);

d - Specimen thickness, in millimeter (mm).

Take the median of the 3 specimens as the test result; keep one decimal place.

10 Test report

The test report shall include the following contents.

a) This standard number or standard name;

b) Name or code of the specimen;

c) Size of the specimen;

d) Temperature and humidity of the test chamber;

e) Test medium;

f) Material and size of the electrode;

g) Voltage boosting method;

......