High Temperature Ball Valve

The sealing characteristics of high-temperature ball valves primarily utilize metal sealing pairs, with the advantage of a wide applicable temperature range. The thermal expansion coefficients of various metals are relatively similar; with proper selection, they can be nearly identical, which helps coordinate thermal deformation. The disadvantage is the high hardness of the materials, which requires high specific pressure for sealing. Even if pre-tightening force is applied to achieve sealing, the high specific sealing pressure causes significant wear between the valve seat and the ball. Additionally, due to the high friction coefficient of metal sealing surfaces, the opening and closing torque of the ball valve is relatively large. Therefore, most high-temperature ball valves use elastic sealing pairs, which are reliable, have strong elastic compensation capabilities, offer a wide applicable temperature range, and are suitable for both floating ball valves and fixed ball valves.

The hardness of the sealing material, hard alloy, can reach 65-70. Our company adopts a single-sided sealing structure: one side uses graphite sealing, while the other side uses a spring to push the valve seat and ball against the opposite side. This design makes the valve very easy to open and close, with excellent sealing performance. Thus, the advantages of high-temperature ball valves include: wear resistance, high-temperature resistance, easy operation, and long service life. High-temperature ball valves are widely used in the extraction, refining, processing, and pipeline transportation systems of petroleum, natural gas, coal, and ores; in the production of chemical products, pharmaceuticals, and food; in power generation systems such as hydropower, thermal power, and nuclear power; and in water supply, drainage, heating, and gas supply systems in cities and industrial enterprises. High-temperature ball valves above 350°C and up to 500°C are high-performance valves developed by our company. The valve seat adopts a leaf spring-loaded metal sealing structure, ensuring easy opening and closing at high temperatures. The ball and valve seat undergo special hardening treatment to prevent sealing surface scratches. The ball valve features bidirectional sealing functionality.

2: Features of High-Temperature Ball Valves:

High-temperature ball valves are high-quality products developed by our company based on the digestion and absorption of new domestic and international technologies. They feature updated design characteristics to meet general industrial standards for safety and convenience.

1. Among various valves, ball valves have relatively low flow resistance. When a full-bore ball valve is open, the ball passage, valve body passage, and connecting pipe diameter are equal and aligned, allowing media to flow through with almost no loss.

2. Ball valves can be fully opened or closed with a 90° rotation, enabling quick operation. Compared to gate valves and globe valves of the same specifications, ball valves are compact, lightweight, and easy to install in pipelines.

3. Opening and closing indication for high-temperature ball valves: The ball, stem, and handle are the moving parts of the valve and form an assembly unit. The stem head adopts a flat structure, making it easy to determine whether the valve is open or closed from the handle position. When the handle or stem flat is parallel to the pipeline axis, the valve is in the open position.

4. Valve locking device: To prevent misoperation, the valve can be locked in the fully open or fully closed position using a lock. This is particularly important for valves installed outdoors or in processes where opening or closing the valve is not allowed. To prevent unauthorized operation, locking the valve position is crucial. Therefore, based on user needs, the valve design includes a positioning plate with lock holes to meet process requirements.

3: Overview of High-Temperature Ball Valves:

High-temperature ball valves can be cast or forged, ensuring sufficient hardness and strength under high rated operating pressures without internal defects. Adequate wall thickness ensures the body can adapt to different high-strength bolts, facilitating maintenance and withstanding pipeline pressure. The valve trim is carefully designed and selected for reliable operation under various working conditions.

a: Fire-safe structure: When the trunnion ball valve is in normal use, its coated valve seat and spherical method, valve seat holder O-ring, and coated body provide soft sealing, ensuring reliable sealing. If the valve seat and O-ring are damaged, the valve seat holder and body will be coated with expanded graphite to achieve fire-safe purposes.

b: Anti-static device: To prevent static electricity generated by friction between the ball, stem, and PTFE from igniting flammable materials and causing accidents, the ball valve, stem, and body are grounded to ensure system safety.

c: Leak-free body sealing structure: The smooth valve opening and closing positions, double-coated gaskets, and O-rings between the valve body and bonnet ensure no external leakage due to fire, high temperature, shock, or uneven opening/closing torque.

d: Low operating torque: Self-lubricating bearings installed on the stem reduce friction, resulting in wear resistance, flexible operation, and low torque.

e: Double block and bleed: When the ball is fully open or closed, the transmitter material in the body cavity can be drained via the drainage and venting device. Additionally, high pressure in the valve cavity can be released to the low-pressure end through the self-relieving seat.

f: Emergency sealing: Composite injection holes and composite injection valves are installed on the stem/bonnet and body to support the valve. If the stem or seat seal is damaged, causing leakage, the compound can be used for secondary sealing. Check valves installed on both sides prevent compound outflow due to media action. The top of the composite injection valve features a quick-connect coupling for the injection gun.

g: Extended stem: For underground valve installation, the stem can be extended for easy operation. Corresponding composite injection nozzles and drain valves can be extended to higher valves.

h: Automatic body cavity relief: If body pressure rises abnormally due to unstable factors, the downstream valve seat of the trunnion ball valve will be under normal pressure while automatically releasing abnormal pressure without damaging the upstream seat seal.

4: Model Description for ZG12CRMOV High-Temperature Ball Valves: Q41H/Y-16I/64I Q47H/Y-16I/100I

5: Main Application Scope of High-Temperature Ball Valves: High-temperature ball valves are suitable for pipelines with Class 150–1500, PN1.6–16.0MPa, working temperatures of -29–425°C (carbon steel) or -40–550°C (stainless steel). They are used to cut off or connect media in pipelines. Different materials can be selected for water, steam, oil, acetic acid, oxidizing media, urea, and other media.

6: Performance Parameters and Material Description for High-Temperature Ball Valves:

a. Working pressure: 1.0Mpa–42.0Mpa.

b. Working temperature: -46 to +550°C.

c. Driving methods: Manual, worm gear, pneumatic, electric, etc.

d. Connection methods: Flange, welding, butt weld, socket weld, etc.

e. Manufacturing standards: National standards GB, JB, HG; American standards API, ANSI; British standard BS; Japanese standards JIS, JPI, etc.

f. Body materials: WC5, WC6, WC9, 1CR5MO, 12CRMOV, ZG1CR5MO, ZG12CRMOV, stainless steel, 304, 304L, 316, 316L, chrome-molybdenum steel, titanium alloy steel, etc.

ZG12CRMOV is an alloy structural steel. Unified number code: A31122

Standard: GB/T 3077-1988

[Chemical Composition] (mass fraction) (%)

Carbon C: 0.08–0.15

Silicon Si: 0.17–0.37

Manganese Mn: 0.40–0.70

Sulfur S: Allowable residual content ≤0.035

Phosphorus P: Allowable residual content ≤0.035

Chromium Cr: 0.30–0.60

Nickel Ni: Allowable residual content ≤0.030

Copper Cu: Allowable residual content ≤0.030

Vanadium V: 0.15–0.30

Molybdenum Mo: 0.25–0.35

This is a pearlitic heat-resistant steel with high organizational stability and thermal strength during long-term high-temperature use. It has low overheating sensitivity during heat treatment and no temper brittleness tendency. The steel has high plasticity during cold deformation and acceptable machinability. Weldability is average, but thick-walled parts require preheating to 200–300°C, and stress relief treatment is needed after welding. This steel is typically used in high-temperature normalized and high-temperature tempered states, with a service temperature range of -40–560°C.

ZG12CRMOV is cast steel, obtained through casting. It can sometimes be used interchangeably, but its strength and impact toughness are inferior to 12CrMOV.

7: National Standard Design for High-Temperature Ball Valves:

Design and manufacturing standards: GB12237—1989 General Purpose Valves—Flanged and Butt-Weld End Steel Ball Valves

Face-to-face dimensions: GB12221;

Connection end dimensions: JB/T79, GB9113, HG20592;

Inspection and testing: JB/T 9092, GB/T13927-1992 General Purpose Valves—Pressure Tests

8: American Standard Design for High-Temperature Ball Valves:

Face-to-face dimensions: ASME B16.10;

Connection end dimensions: ASME B16.5, ASME B16.25;

Inspection and testing: API598;

Fire-safe design: API607;

9: Installation Instructions for Our Company’s High-Temperature Ball Valves:

a: Remove the protective covers on both flange ends and flush clean the valve in the fully open state.

b: Before installation, perform a full test according to the specified signal (electric or pneumatic) to prevent transportation-induced vibration from affecting performance. Install only after passing the test (wiring according to the electric actuator circuit diagram).

c: Before connecting to the pipeline, flush and clean any residual impurities in the pipeline (these may damage the valve seat and ball).

d: During installation, do not use the valve’s actuator as a lifting point to avoid damaging the actuator and accessories.

e: This type of valve should be installed horizontally or vertically in the pipeline.

f: Ensure there is no sagging or external force on the pipeline near the installation point. Use pipeline supports or braces to correct any misalignment.

g: After connecting to the pipeline, cross-tighten the flange connection bolts with the specified torque.

10: Customer Ordering Information:

a: Product name and model of ZG12CRMOV high-temperature ball valve

b: Operation method of ZG12CRMOV high-temperature ball valve (manual, worm gear, pneumatic, electric, etc.)

c: Sealing surface material and hardness of ZG12CRMOV high-temperature ball valve

d: Body material of ZG12CRMOV high-temperature ball valve

e: Pressure of ZG12CRMOV high-temperature ball valve

f: Media used for ZG12CRMOV high-temperature ball valve (name, viscosity, particles, corrosiveness, toxicity)