12) De-pressuring & Degassing of Cylinder
De-pressuring and degassing of a CNG (Compressed Natural Gas) cylinder refers to the process of safely emptying the cylinder of its gas content before conducting any maintenance, testing, or repairs. Here’s an overview of the de-pressuring and degassing process for a CNG cylinder:
Safety Precautions: Before de-pressuring or degassing a CNG cylinder, it is crucial to follow proper safety precautions. This includes wearing appropriate personal protective equipment (PPE) such as safety glasses, gloves, and a face shield. It’s also important to work in a well-ventilated area away from ignition sources and to adhere to all relevant safety guidelines and procedures.
Shutting Off Cylinder Valve: Begin by ensuring that the cylinder is securely mounted in a vertical or approved position. Locate the cylinder valve, which is typically located on the top of the cylinder, and make sure it is closed tightly. This valve is responsible for controlling the flow of gas into and out of the cylinder.
Venting Cylinder Pressure: To de-pressurize the cylinder, you need to release the gas pressure inside. Locate the pressure relief device or pressure relief valve on the cylinder. This valve is designed to release pressure automatically if it exceeds a certain limit. Carefully activate the pressure relief device following the manufacturer’s instructions. This will allow the gas to escape slowly and safely until the pressure inside the cylinder is fully released.
Purging Remaining Gas: After venting the pressure, it’s important to ensure that all remaining gas is purged from the cylinder. This can be done by slowly opening the cylinder valve for a short period, allowing any residual gas to escape. It’s important to perform this step in a well-ventilated area to prevent the accumulation of gas.
Cylinder Inspection: Once the cylinder is de-pressurized and purged, it is recommended to conduct a visual inspection for any signs of damage, corrosion, or other visible defects. This inspection helps identify any issues that may need to be addressed before further maintenance or testing.
Securely Cap Cylinder Valve: After de-pressuring and inspecting the cylinder, securely cap the cylinder valve using an appropriate valve cap. This helps prevent the entry of contaminants and ensures the safety of the cylinder during storage or transportation.
It’s important to note that de-pressuring and degassing a CNG cylinder should only be performed by trained professionals or individuals with the necessary knowledge and experience. If you are unsure about the process or have concerns, it is recommended to seek assistance from an authorized facility or technician who can safely handle CNG cylinders.