The instrument is manufactured for Thermal Ageing test under oxygen air pressure for insulation & sheath of electric cables.
The instrument is manufactured for Thermal Ageing test under oxygen air pressure for insulation & sheath of electric cables. This apparatus is also used for estimating the relative resistance of vulcanized rubber to age determination by assessment of change in tensile strength & elongation of material by subjecting them to accelerated ageing in oxygen air pressure.Temperature Range : Ambient to 200oCPressure Range : 0-22 Kg/cm2 (0-2.2 Mpa) .StandardThe instrument conforms to IS: 10810 (Pt.16), IS: 10810 (Pt.56), Appendix A of IS 6380 – 1984 and IEC 60811-1-2 InstrumentThe instrument consist of the following : Inner chamber of seamless steel pipe of at least 6 mm thickness SS lid and provision for placing the rubber test pieces, Pressure Control by Digital Pressure Controller Jacket Heaters outside the Inner Chamber PID Digital Temperature Indicating Controller , least count 0.1oC Pressure Gauge Digital (least count 0.1 kg/cm2, ) Inlet, outlet for Air and Oxygen with Solenoid Valves to control the flow Safety valve (preset / sealed at 25 kg/cm2) Unique Feature : If the pressure drops very rapidy, the syetem automatically shuts of input valve isolating the cylinder. Manifold with pressure switch, solenoid valve for compensating drop in pressure of gas from cylinders Power cord, extra seal, rubber pipe to connect bomb with cylinder The sample is kept inside the pressure chamber under high temperature and pressure for the desired time period. After the time period is over, the sample is tested visually for any creaks or deformations and also physical test are preformed like tensile and elongation to determine the change as a result of ageing.Safety Feature The Chamber is designed with four safety devices for over shoot of pressure.a) The input is regulated by digital pressure control which switch off the solenoid value once the desired pressure is reached.b) A separate pressure switch with solenoid value is provided in series with the first solenoid value. The value of this pressure switch is set slightly higher than the set value, and will cut off the pressure if the digital pressure control fails.c) A release value is provided on the top, set at ~25 kg/cm2 and will release the pressure if both the solenoid fails. d) If the pressure drops very rapidly, the PLC assumes that either the gas is being released manually or there is some leakage. In both cases, the system shuts off the input valve and isolating the chamber form the gas cylinder. This prevents the wastage of gas and also provides protection in case of leakage.
