LPG Cylinder Refurbishing and Re-qualification
Guided by the cylinder management policy of the company, monitoring teams look for external inspection defects. If an LPG cylinder exceeds the maximum limit of dents, bulges, etc., the cylinder is considered substandard and will be rejected. However, a cylinder that passes the visual inspection, but needs repair and re-qualification, can be pressure tested and sandblasted before refilling.
A hydrostatic test is a way in which gas cylinders can be tested for strength and leaks. The test involves filling the vessel or pipe system with a liquid, usually water, which may be dyed to aid in visual leak detection, and pressurization of the vessel to the specified test pressure. Pressure tightness can be tested by shutting off the supply valve and observing whether there is a pressure loss.
Sand blasting is the operation of forcibly propelling a stream of abrasive material on cylinders under high pressure to smoothen, shape cylinder surface, or remove surface contaminants. A pressurized fluid, typically air, or a centrifugal wheel is used to propel the blasting material. This process improves the quality of inner cylinder, abrasion and corrosion resistance and life of resistance to vibration and shock.