What is the working pressure and temperature range of high-temperature and high-pressure gate valves?

2025-04-18 08:50:04

The working pressure and temperature range of high-temperature and high-pressure Gate valves need to be determined based on specific materials, structural design, and industry standards. The following are common ranges and explanations:

1、 Range of work pressure

1. Conventional pressure level

National standard (GB)/European standard (EN):

PN16（1.6MPa）~ PN1000（100MPa）， Commonly used in high-pressure scenarios such as power stations and petrochemicals, such as PN32, PN64, and PN100 (corresponding to 32MPa, 64MPa, and 100MPa).

American Standard (ASME/API):

Class 150（2.0MPa）~ Class 2500（42.0MPa）， High pressure conditions commonly use Class 900 (15.0MPa), Class 1500 (25.0MPa), and Class 2500 (42.0MPa).

2. Special high-voltage scenarios

In fields such as supercritical power plants and deep-sea oil and gas extraction, special designs (such as forged steel valve bodies and high-strength sealing structures) can achieve pressures of over 100MPa (customized).

2、 Working temperature range

1. Temperature corresponding to conventional materials

Carbon steel (such as WCB): The maximum temperature resistance is about 425 ℃ (exceeding this temperature can easily cause graphitization, leading to a decrease in strength).

Low alloy steel (such as 15CrMo, 12Cr1MoV): with a temperature resistance range of 450 ℃~550 ℃, commonly used in high-temperature steam pipelines of power plants.

High alloy/heat-resistant steel (such as F91, F92, Inconel): can withstand 550 ℃~700 ℃, suitable for high parameter working conditions such as supercritical/ultra supercritical boilers.

2. Special low-temperature scenarios

Some high-temperature and high-pressure gate valves need to take into account low-temperature working conditions (such as alternating cold and hot environments), and can work stably within the range of -20 ℃~700 ℃ (customized) through material low-temperature toughness treatment (such as nickel based alloys).

3、 Key influencing factors

Material matching:

When the temperature exceeds 540 ℃, austenitic stainless steel (such as 316H) or high-temperature alloy should be used to avoid insufficient durability strength of pearlite steel;

The higher the pressure, the more stringent the requirements for valve body wall thickness, connection form (welding/flange), and sealing surface hardness (such as welding hard alloy Stellite).

Industry standards:

Valves used in power stations shall comply with JB/T 3595 ASME BPVC Section III；

Valves used in petrochemicals comply with API 600 GB/T 12234， Special requirements such as fire prevention and sulfur resistance (such as NACE MR0175) must be met.

Actual working condition limitations:

The characteristics of the medium (such as particle content and corrosiveness) can affect the allowable pressure and temperature range, and reliability needs to be improved through derating design or special sealing structures (such as metal hard seals).

4、 Selection precautions

Refer to the manufacturer's specification sheet: There are significant differences in product design between different manufacturers (such as structural length, pressure and temperature rating tables), and specific model parameters should be followed;

Adaptation to working conditions: Clearly define the medium (steam/oil/gas), maximum/minimum operating parameters (to avoid failure caused by short-term overheating and overpressure);

Certification requirements: In high-pressure scenarios, it is necessary to ensure that the valve passes compliance testing such as pressure testing (such as API 598 hydrostatic testing) and material retesting (such as spectral analysis).

In summary, the typical range of high-temperature and high-pressure gate valves is a pressure of 10MPa~100MPa and a temperature of 425 ℃~700 ℃. The specific range needs to be determined comprehensively based on the working conditions, materials, and industry standards. Special working conditions can be customized to exceed the conventional range.