ABSTRACT
Valves are known as essential parts of the piping system, and they are used for different purposes such as stopping or starting the fluid inside the piping also called on/off application, regulating or controlling the fluid, preventing backflow and performing safety functions. Actuators are either electrical or mechanical device or a combination of both which are used to automate and control the motion of the valves. The reliability and good performance of the valve are largely dependent on the actuators. This chapter explains the important valves which are used in offshore oil and gas including both topside and subsea such as ball, gate, butterfly, modular, globe, axial, swing check, dual plate, etc. In addition, different types of actuators such as pneumatic, hydraulic, electro-hydraulic and electrical types applicable for both topside and subsea are covered in this chapter. In addition, different options for offshore development such as platforms and floating production storage and offloading (FPSO) are covered. In addition, subsea structures such as wellhead, Christmas trees and manifolds where subsea valves and actuators are located are explained.
