What are The Valves in The Petroleum Pipeline?

The oil pipeline is composed of the oil pipe and its accessories such as forged steel valve and cast steel valve. According to the needs of the technological process, it is equipped with the corresponding oil pump unit, which is designed and installed into a complete pipeline system to complete the oil loading and unloading and transmission tasks. 

Connection Mode of Oil Pipeline

In order to form a complete system, a certain connection mode must be used in the oil pipeline. There are three main types of pipe connection: screw thread connection, welding and flange connection. The pipe with small diameter can be connected by screw thread, which is more convenient. However, because the diameter of most main oil pipelines is generally large, the other two connection methods are often used. The pipes with DN≥50 are basically connected by welding, which has the advantages of convenient construction, firmness, tightness and steel saving. Flanges are used to connect pipes to valves or other equipment, as well as to detachable components on the pipes. To ensure the tightness of the flange connections, both sides of the flanges require a relatively soft flange gasket for auxiliary connections. According to the manufacturing process, flanges can be divided into flat welding flanges, threaded flanges, welding neck flanges, loose flanges and blind flanges. Besides blind flanges, other types of flanges can be used to connect pipes. Adapter flanges corresponding to pipe diameters may also be used if pipes with different diameters need to be connected. Blind flanges are used to close one end of a pipe and therefore can withstand high bending stresses.

Valves Used in Oil Pipeline

Valves are mechanical devices used to open, close or control the flow of media in pipes. There are many types of valves and different classification methods. The valves can be divided into cut-off valves, check valves, distribution valves, etc. according to their use. The valves can be divided into vacuum valves, low pressure valves, medium pressure valves and high pressure valves according to pressure. And the valves can be divided into manual valves, power-operated valves and automatic valves according to the mode of actuation. Due to the characteristics of gate valves, gate valves are generally used for fully open or fully closed regulation, and they have the advantages of good sealing performance and easy maintenance. The spool of the cut-off valve falls vertically on the base and the seat is parallel to the pipeline centerline. Fluid is flowing in the form of "S" in the valve body, so it is subject to greater resistance. The cut-off valves are generally used for flow regulation and have the advantages of easy fabrication and maintenance, but they have less sealing than gate valves.

In the petroleum industry, the valves used are mainly forged steel valves, stainless steel valves and cast steel valves. Valves are required at both ends of oil pipelines when crossing large rivers, lakes, reservoirs and towns. The setting position of the cut-off valve can not be affected by geological disasters and floods, and it should meet the needs of convenient transportation and overhaul.