VALVES

The gate valve, also known as a sluice valve, is a valve that opens by lifting a round or rectangular gate/wedge out of the path of the fluid. The distinct feature of a gate valve is the sealing surfaces between the gate and seats are planar, so gate valves are often used when a straight-line flow of fluid and minimum restriction is desired. The gate faces can form a wedge shape or they can be parallel. Gate valves are primarily used to permit or prevent the flow of liquids, but typical gate valves shouldn’t be used for regulating flow, unless they are specifically designed for that purpose. Because of their ability to cut through liquids, gate valves are often used in the petroleum industry. For extremely thick fluids, a specialty valve often known as a Typical gate valves are designed to be fully opened or closed. When fully open, the typical gate valve has no obstruction in the flow path, resulting in very low friction loss.

Bonnets provide leakproof closure for the valve body. Gate valves may have a screw-in, union, or bolted bonnet. Screw-in bonnet is the simplest, offering a durable, pressure-tight seal. Union bonnet is suitable for applications requiring frequent inspection and cleaning. It also gives the body added strength. Bolted bonnet is used for larger valves and higher pressure applications. Gate valves are typically constructed from cast iron, ductile iron, cast carbon steel, gun metal, stainless steel, alloy steels, and forged steels.

PRESSURE RATING: PN 25

WORKING TEMPERATURE: WATER BELOW 120°C, OIL, GAS, STEAM BELOW 170°C

THREADS: NSI B1.20.1 (NPT)

AVAILABLE SIZES: ½ ”, ¾ ”, 1”, 1 ¼”, 1 ½ ”, 2”, 2 ½ ”, 3”

A ball valve is a valve with a spherical disc, the part of the valve which controls the flow through it. The sphere has a hole, or port, through the middle so that when the port is in line with both ends of the valve, flow will occur. When the valve is closed, the hole is perpendicular to the ends of the valve, and flow is blocked. The handle or lever will be inline with the port position, letting you “see” the valve’s position. Ball valves are durable and usually work to achieve perfect shutoff. They do not offer the fine control that may be necessary in throttling applications, but are sometimes used for this purpose.

The body of ball valves may be made of metal, plastic or metal with a ceramic center. The ball is often chrome plated to make it more durable.

PRESSURE RATING: PN 25
WORKING TEMPERATURE: WATER BELOW 120°C, OIL, GAS, STEAM BELOW 170°C
THREADS: ANSI B1.20.1 (NPT)
AVAILABLE SIZES: ½ ”, ¾ ”, 1”, 1 ¼”, 1 ½ ”, 2”

A check valve, clack valve, non-return valve or one-way valve is a valve that normally allows fluid to flow through it in only one direction. Check valve is simply a freely hinged flap which drops to obstruct fluid flow in one direction, but is pushed open by flow in the opposite direction.

Check valves are two-port valves, one for fluid to enter and the other for fluid to leave. There are various types of check valves used in a wide variety of applications. Check valves are often part of common household items. Although they are available in a wide range of sizes, check valves generally are very small, simple or inexpensive. Check valves work automatically and most are not controlled by a person or any external control; accordingly, most do not have any valve handle or stem. The bodies of most check valves are made of plastic or metal.