High Temperature Check Valve

Description

What is a High Temperature Valve?

When choosing a valve design and material selection, the working temperature of the valve should be compatible with the valve body and trim materials. High-Temperature Valves are found in the petrochemical, chemical, fertilizer, electric power, and metallurgy industries. The material properties of non-ferrous, carbon steel, and alloy grades, are specified according to the limits of the material. Bronze, for example, cannot exceed 550F degrees, therefore not considered high temperature. High-temperature grades are:

Sub-high temperature

Sub-high temperature valves refer to the working temperature of the valve between 625f and 800f degrees.

WCB, WCC, A105, WC6, and WC9 are mainly used for corrosive services in this range: C5, CF8, CF3, CF8M, and CF3M is used

High-Temperature Level I

High-Temperature Level I is the working temperature of the valve within the range of 800f and 1025f degrees.

Materials within this range are based on CF8 Stainless steel in the ASTM A351 family.

High-Temperature Level II and Level III

High-Temperature Level II and Level III are within the working temperatures of the valve within the range of 1025f and 1350 degrees.

Materials within this range are based on CF8 Stainless steel in the ASTM A351 family.

For Temperatures above 1350f, the working temperature of the valve is classified as high-temperature Class IV and Class V. This requires application-specific recommendations and cannot be quoted routinely as the pressure-temperature level may cause plastic deformation.

Pressure /Temperature Matrix

Cast Steel or forged steel valves can be made of carbon steel or stainless steel alloys and trims are capable of handling 1000f degree temperatures at up to 10,000 psi. These valves are made with metal to metal full hard-faced seats, or various chrome-moly alloys and exotic materials like Monel 400, Hastelloy C276, Inconel 600, and Inconel 625.

How are valves specified for pressure-temperature?

ASME B16.34 Pressure Temperature Table groups materials by pressure and temperature for recommended application.

High Temperature Groups Materials

For example, Gate valves, globe valves, stop-check valves, and Check valves have recommended material combinations based upon the ASME B16.34 Pressure Temperature Table. SA 182 F11, SA 182 F22, SA 182 F316, ASTM A351 CF8M, A 351 CN7M, C-276, A217 WC6, A217 WC9, A216 WCB, A352 LCB, A352 LCC, A352 LC2, A352 LC3, A217 WC1, A217 WC4, A217 WC6, A217 WC9, A 217 C5 all carry different capabilities for pressure, temperature and corrosion resistance.

An additional factor determining valve limitations are packing and gasket materials, which can be made of Grafoil or Graphite for higher temperatures, Teflon for temperatures under 500F degrees, and high temperature two-ply and three-ply Monel bellows.

Features of High Temperature Check Valve

• For extremely high temperatures or cryogenic applications, valves may be equipped with high-temperature extensions.
• The packing is thus removed from the high- or low-temperature valve body.
• Valve body made of AISI 316Ti stainless steel.
• Two-piece stem with non-rotating lower stem increases service life of packing and seat.
• Large handle for easy operation at highest pressures. Minimum required torque and no backlash problems.
• Leakproof with gases and liquids.
• Inert PTFE or silver packing ring.
• Safety weep holes on tubing connections and packing.
• Connections for inch and metric SITEC HP tubing.
• Fluid working temperature –200°C (–300°F) to +300°C (570°F). With cooling jacket on the high-tem perature extension up to +450°C.
• All our valves are equipped with gland nuts and collars.
• All valves are factory tested and available short-dated.

Material of High Temperature Check Valve

No	Part	Material
1	Body	ASTM A217 WC9
2	Seat	ASTM A182 F22 + STL
3	Disc	ASTM A217 WC9 +STL
4	Arm	ASTM A217 WC9
5	Nut	ASTM A194 4
6	Pin	ASTM A182 F6a
7	Connector	ASTM A217 WC9
8	Gasket	Graphite + SS316
9	Bonnet	ASTM A217 WC9
10	Bolt	ASTM A193 B16