What are the common faults of pressure vessels?

I. Cracks

Manifestations: Cracks appear in the vessel wall or weld area, which may lead to brittle fracture, fatigue cracking, or corrosion cracking.

Causes: Manufacturing defects, stress concentration during use, or corrosive media.

Treatment: Cracks are detected through visual inspection and non-destructive testing (such as penetrant testing and magnetic particle testing). Severe cases require component replacement.

II. Corrosion

Manifestations: Corrosion occurs on the inner and outer surfaces of the vessel due to chemical or electrochemical reactions, such as uniform corrosion, pitting corrosion, and intergranular corrosion.

Causes: Media corrosion, failure of anti-corrosion measures, or deterioration of process conditions.

Treatment: Minor corrosion can be monitored during use; severe corrosion requires pressure reduction or component replacement.

III. Deformation

Manifestations: Localized dents, bulges, or overall expansion of the vessel.

Causes: Excessive pressure, structural defects, or operation at excessive temperatures.

Treatment: Minor deformation can be monitored; severe deformation requires professional inspection.

IV. Safety Accessory Malfunction

Pressure Gauge: Inaccurate reading or blocked pressure tap.

Safety Valve: Leaking, frequent tripping, or failure to trip.

Level Gauge: False level reading or mechanical transmission malfunction.

Handling: Regular calibration; replace immediately if abnormal.

V. Leakage

Symptoms: Medium leaks from the sealing surface or cracks in the vessel wall.

Causes: Seal failure, corrosion perforation, or bulging/deformation.

Handling: Immediately stop operation, inspect and replace damaged parts.

VI. Overpressure

Symptoms: Pressure exceeds the allowable range.

Causes: Operational error, safety accessory malfunction, or process abnormality.

Handling: Immediately reduce pressure and notify relevant departments to investigate the cause.

VII. Explosion

Symptoms: Container rupture leading to an explosion.

Causes: Overpressure, medium mixing, or safety accessory malfunction.

Handling: Immediate evacuation and activation of the emergency response plan.