Pipeline Pigging Safety
What is Pipeline Pigging?
Pipeline pigging is a common maintenance operation in the oil and gas industry. A "pig," or pipeline inspection gauge, is a tool that's sent through a pipeline to perform a variety of tasks, such as cleaning, inspecting, or separating different products. The pig is propelled by the pressure of the fluid in the pipeline.
The Hazards of Pigging
The primary hazards of pigging operations are the uncontrolled release of flammable or toxic substances and the potential for ignition. When a pig is launched or received, a pressurized section of the pipeline is opened to the atmosphere. If the pressure is not properly managed or if there's a malfunction, a sudden release of hydrocarbons or other chemicals can occur. Sources of ignition, which can be as simple as static electricity, a hot surface, or a nearby engine, can then lead to a fire or explosion.
How Standards Could Help
API Recommended Practice 1165, "Recommended Practice for the Selection and Application of Pipe-Type Pipe-Type Pigs": This standard provides guidance on the selection and use of pigs, including safety considerations. Adherence to this standard could help in the following ways:
Pressure Control: The standard emphasizes the need for proper control of pressure during launching and receiving operations. This could include using specialized equipment to manage pressure and flow rates, which can help prevent sudden, uncontrolled releases.
Controlling Ignition Sources: The standard recommends controlling ignition sources in the vicinity of the pigging operation. This would involve a hot-work permit system and a detailed job safety analysis (JSA) to identify and mitigate potential ignition sources.
Personnel Training: API 1165 also highlights the importance of proper training for personnel involved in pigging. Trained workers are more likely to follow established safety procedures and recognize and respond to hazardous conditions.
Sources of Information
API Recommended Practice 1165, American Petroleum Institute.