Structural Steel
October 28, 2020Fittings
October 28, 2020Valves
Valves
Valves are mechanical devices that control the flow and pressure within a system or process. They are essential components of a piping system that conveys liquids, gases, vapours, slurries, etc.
Different types of valves are available: gate, globe, plug, ball, butterfly, check, diaphragm, pinch, pressure relief, control valves, etc. Each of these types has a number of models, each with different features and functional capabilities. Valves are available in a wide range of material ranging from cast Iron, Stainless Steel, & Tungsten Carbide. Some valves are self-operated while others manually or with an actuator or pneumatic or hydraulic is operate
Functions of Valves Are:
- Isolation ( Stopping ) and starting flow
- Reduce or increase a flow
- Controlling the direction of flow
- Regulating a flow or process pressure
- Relieve a pipe system of a certain pressure
Class Ratings
Pressure-temperature ratings of valves are designated by class numbers. ASME B16.34, Valves-Flanged, Threaded, and Welding End is one of the most widely used valve standards. It defines three types of classes: standard, special, and limited. ASME B16.34 covers Class 150, 300, 400, 600, 900, 1500, 2500, and 4500 valves.
Valves Specifications
API STANDARDS- API 6D Specification for pipeline valves
- API 6FA Fire test for valves
- API 598 Valve inspection and testing
- API 600 Steel gate valves, flanged and buttwelding ends, bolted and pressure seal bonnets
- API 602 Compact steel gate valves - flanged, threaded, welding, and extended body ends
- API 607 Fire test for soft seated quarter turn valves
- API 608 Metal ball valves - flanged and butt welding ends
- ASME/ANSI B16.34 Valves - flanged, threaded and welding end
- ASME/ANSI B16.5 Pipe flanges and flanged fittings
- ASME/ANSI B16.10 Face-to-face and end-to-end dimensions of valves
- ASME/ANSI B16.11 Forged fittings, socket-welding and threaded
- ASME/ANSI B16.25 Buttwelding ends
- ASME/ANSI B16.47 Large diameter steel flanges