GB/T 7759-1996
Rubber, Vulcanized or thermoplastic--Determination of compression set at ambient elevated or low temperatures (English Version)
- Standard No.
- GB/T 7759-1996
- Language
- Chinese, Available in English version
- Release Date
- 1996
- Published By
- General Administration of Quality Supervision, Inspection and Quarantine of the People‘s Republic of China
- Status
- 2015-10
- Replace By
- GB/T 7759.1-2015
- GB/T 7759.2-2014
- Latest
- GB/T 7759.1-2015
- GB/T 7759.2-2014
- Scope
- This standard specifies the deformation of vulcanized rubber and thermoplastic rubber after a certain compression time at a specified compression rate under normal temperature, high temperature and low temperature conditions. This standard also stipulates that when the rubber hardness value is 10-80, the compression rate is 25%. When the rubber hardness value is greater than 80, the compression rate is 15% and 10% when the rubber hardness value is 80-89 and 90-95, respectively. This standard is also applicable to the determination of rubber compression set under the action of liquid. Note: When rubber is in compression, physical and chemical changes will inevitably occur. These changes prevent the rubber from returning to its original state when the compressive force is removed, and compression set occurs. The size of the compression set depends on the temperature and time in the compressed state, and the temperature and time in the recovery height. At high temperatures, chemical changes are the main cause of compression set in rubber. Compression set is measured after removing the compressive force applied to the sample and recovering its height at standard temperature. At low temperatures, changes due to glass hardening and crystallization are dominant. These effects disappear when the temperature rises. It is therefore necessary to measure the specimen height at the test temperature.
GB/T 7759-1996 history
- 2015 GB/T 7759.1-2015 Rubber, vulcanized or thermoplastic.Determination of compression set.Part 1:At ambient or elevated temperatures
- 1996 GB/T 7759-1996 Rubber, Vulcanized or thermoplastic--Determination of compression set at ambient elevated or low temperatures
