1. To protect individuals and equipment
Safety valves are installed in process and storage equipment to release pressure that is beyond the limits that cause operating failure, external combustion and other hazards. A good design and properly installed from a Safety valve that is maintained in good operating conditions is important for the safety of the individual and protection of equipment in an abnormal condition.
2. To Determine the Condition of the Device
Inspection of the Safety valve must determine the general conditions and operating conditions of the equipment. In this examination there are 2 parts, which are interrelated:
- Inspection of Safety valve conditions to check external conditions and workability tests
- Inspection of protected equipment to find conditions that can interfere with the work function of the Safety valve, for example: Cores, Corrosion, and others.
3. To Evaluate Inspection Frequency:
Safety valve checks produce data that can be evaluated to analyze safe and economical inspection frequencies.
Inspection of the safety valve in the tank
The safety valve in the tank is somewhat different due to the type of pressure and vacuum relief device and due to the large size and the amount which is always more than one inspection and testing it likes to be done when tanking in service. The inspection procedure is the same, there are only a few special steps as follows:
- Sticking must always be prevented, so the disk must be checked
- The disk must be checked and maintained, because the mass may change so it must be added or reduced
- Seats and pallets must be checked and cleaned
- Gaskets and disk seating must be checked and may be replaced
- The protective screen, check and may need to be replaced.
- Hinges and hinge pins: checked and if necessary given grease or replaced
- There may be a damaged internal or external coating
- The hood must be checked
- The bolt may rust and needs to be replaced.
Inspection of the safety valve on the boiler:
Although it is still the same but the inspection sometimes must be based on local government regulations because in ASME SEC I PPT Boilers must be checked periodically when installed. But the safety valve on the boiler must be regularly removed and tested at the work shop.