What is OS&Y Gate Valve and IS&Y?
Gate valves shall be of the OS&Y or IS&Y type.
OS&Y stands for Outside Screw and Yoke. When the handwheel of the OS&Y gate valve is rotated to open the valve, the valve stem will rise.
Here are some examples of OS&Y gate valve specification parameters: ASME B16.10, API 602, ASTM A182-F304, TRIM.15-HF, CL150, BB and OS&Y.
Corresponding to OS&Y, there is also IS&Y, which stands for Inside Screw and Yoke. When the handwheel of IS&Y valve is rotated to open the valve, the valve stem will not rise.
Internal structure and difference comparison between OS&Y gate valve IS&Y gate valve.
The following are the internal structure diagrams of OS&Y and IS&Y valves. On the left is the OS&Y gate valve, and on the right is the IS&Y gate valve.
Ⅰ. Schematic diagrams of OS&Y and IS&Y valves.
When the handwheel of the OS&Y valve rotates, the valve stem does not rotate but rises, and the valve disc rises. When the handwheel of the IS&Y valve rotates, the valve stem rotates but does not rise, and the valve disc rises.
Ⅱ. Internal structure and physical diagram of the OS&Y valve.
Ⅲ. Internal structure and physical diagram of the IS&Y valve.
Advantages and disadvantages of OS&Y gate valve.
Advantages:
It can accurately control the opening and closing state of the gate valve during operation and also achieve the regulation of the flow rate.
The internal structure of the valve is simple, and the failure rate is low.
There is basically no obstruction between the inner cavity of the gate valve and the inner wall of the pipeline, resulting in low flow resistance.
Disadvantages:
It is large in size and relatively inconvenient for installation and maintenance.
The price is relatively high.
Advantages and disadvantages of IS&Y gate valve.
Advantages:
Cost-effectiveness: The IS&Y design is generally more cost-effective than the OS&Y design because its structure and manufacturing process are relatively simple.
Easy Maintenance: The valves with the IS&Y design are easier to maintain and disassemble, which can save time and costs during the use process.
Disadvantages:
Poor Sealing Performance: Due to the relatively small sealing surface of the IS&Y design, its sealing performance may be inferior to that of the OS&Y design, which may increase the risk of leakage.
Limited Applicability: The IS&Y design is generally suitable for applications with lower pressure. It may not be ideal for occasions that require higher sealing performance and pressure resistance.
In conclusion, when the OS&Y valve is opened and closed, the valve stem will have a lifting action. Through the position of the valve stem, the opening and closing state of the valve can be indicated. OS&Y is also the most commonly used structure for gate valves.
The valve stem of the IS&Y valve will be in contact with the medium. The IS&Y valve is often used in occasions where the space is limited and the medium will not cause corrosion or wear to the valve stem.
