Indian Boiler Course presents this topic in a plant-oriented, examination-ready format. The lesson combines principles, construction, operation, safety, inspection points, troubleshooting and revision questions.
Function
Protects the boiler against pressure above the permissible limit. Study set pressure, blowdown, accumulation, discharge capacity, easing gear, gagging precautions, testing and common leakage causes.
Construction and Working
Identify the body, flow path, moving parts, sealing surfaces, actuation method, instrumentation and isolation provisions. Relate each component to the failure it prevents.
Operating Checks
- Correct line-up and accessibility
- No leakage, blockage, abnormal vibration or overheating
- Valid calibration or functional test where applicable
- Clear identification and documented maintenance history
Common Faults
Typical faults arise from deposits, corrosion, erosion, misalignment, wrong adjustment, instrument failure, sticking, leakage or unsuitable operating conditions.
Exam Questions
- State the purpose and explain working.
- Draw a labelled sketch.
- List failure modes and safety consequences.
- Describe testing and inspection.