Tungsten carbide Valve Stem and Seat

Product Description

Tungsten carbide valve stems and tungsten carbide seats are precision-engineered from ultra-high hardness tungsten carbide, specifically designed for high-pressure, high-temperature, and highly corrosive environments. Leveraging advanced materials science and precision manufacturing techniques, they upgrade traditional wear-prone valve components into durable, highly reliable core parts. Using tungsten carbide valve stems and seats can significantly extend valve service life, reduce maintenance costs, and ensure stable sealing and dependable operation under extreme conditions.

Features

Specification

Parameter Category	Tungsten Carbide Valve Stem	Tungsten Carbide Valve Seat
Common Specs & Model	Diameter: Φ6~Φ150mm Length: L50~L800mm Standard Code: WC-ValveStem-Φ×L (e.g., Φ20×200) Fit for ball valve/gate valve/globe valve/control valve	Inner Diameter: Φ8~Φ160mm  Outer Diameter: Φ15~Φ200mm Thickness: 5~50mm Standard Code: WC-ValveSeat-ΦID×ΦOD×T (e.g., Φ22×35×8) Fit for DN8~DN150 valves
Material Grade	YG6 (High hardness, low impact) YG8 (Universal wear resistance) YG10X (High toughness, impact resistance) YG12 (Strong impact, corrosion resistance)	YG6 (High hardness for sealing surface) YG8 (Universal working condition) YG10X (Particle medium) YG15 (Ultra toughness, impact resistance)
Hardness	YG6:89~91; YG8:88~90; YG10X:87~89; YG12:86~88 Uniform overall hardness ≥86 HRA	YG6:89~91; YG8:88~90; YG10X:87~89; YG15:86~88 Sealing surface hardness ≥88 HRA (core requirement)
Density	14.3~15.0 YG6:14.7~15.0; YG8:14.6~14.9; YG10X:14.4~14.7; YG12:14.3~14.6	14.2~15.0 YG6:14.7~15.0; YG8:14.6~14.9; YG10X:14.4~14.7; YG15:14.2~14.5
Cobalt Content	6%/8%/10%/12% Co, customizable 4%~15% Co for special demand	6%/8%/10%/15% Co, low-cobalt high-hardness modification available for sealing surface
Wear Resistance	12~20 times that of stainless steel, 8~15 times that of alloy steel Resists abrasive/erosion wear, suitable for solid-containing medium	Sealing surface: wear-resistant & anti-scuffing, 10~30 times longer service life than metal valve seats No obvious wear after repeated opening/closing, durable sealing performance
Tolerance	Diameter: h5/h6 (h6: -0.006~-0.018mm) Length: ±0.05~±0.2mm Coaxiality/Straightness: ≤0.003mm/m Roundness: ≤0.002mm	Inner Diameter: H6/H7 (H7: +0.010~+0.030mm) Outer Diameter: h6/h7 (h7: -0.010~-0.030mm) Thickness: ±0.02~±0.05mm Sealing surface flatness: ≤0.001mm
Dimensional Accuracy	Diameter Precision: ±0.002~±0.005mm End Face Per Pendicularity: ≤0.005mm Surface Roughness: Ra≤0.1μm (matching surface)	Sealing Surface Roughness: Ra0.02~0.05μm (mirror finish) Inner/Outer Diameter Precision: ±0.003~±0.008mm Coaxiality: ≤0.005mm
Applicable Working Conditions	Temperature: -60℃~+500℃  Pressure: ≤40MPa Suitable for acid-alkali, sand-containing, crude oil, chemical slurry medium	Temperature: -60℃~+550℃  Pressure: ≤64MPa (high-pressure type) Fit for DN8~DN150 ball/gate/check valves, resistant to acid-alkali, particle, high-pressure medium

Typical Applications

1. Upstream Oil and Gas Exploration

In wellhead equipment, Christmas trees, high-pressure water injection systems and fracturing systems, valves must be able to withstand high pressures and be resistant to media containing large quantities of hard particles, such as formation sand and rock debris. Tungsten carbide stems and seats can withstand this extreme abrasive wear effortlessly, ensuring that critical valves maintain tight seals, even when they are subject to frequent cycling, to prevent wellhead blowouts.

2. Demanding Conditions in Refining and Chemical Processes

Valves in refinery hydrocracking and catalytic cracking units, as well as in the reaction feed lines and high-temperature, high-pressure separation units of chemical plants, face multiple challenges, including extreme temperatures and pressures, as well as corrosion from hydrogen, sulphur and acids. The exceptional corrosion resistance and high-temperature stability of tungsten carbide make it the preferred material for shut-off and control valves in these critical pipelines.

3. Black Water and Ash Water Treatment in Coal Chemicals and Gasification

Black and grey water generated by coal gasification units is characterised by high temperatures and pressures, and contains large quantities of extremely fine ash particles. This makes the water highly abrasive, earning it the nickname ‘liquid sandpaper’. Under these conditions, conventional valves can suffer severe wear and failure within days or weeks. The only reliable solution to ensure the continuous, stable operation of these systems for months or longer is slurry-proof valves, pressure-reducing valves and circulation valves equipped with tungsten carbide seats and stems.

4. Core Protection for Multistage Centrifugal Pumps — Minimum Flow Valves

To prevent cavitation damage in high-pressure multistage centrifugal pumps (e.g. boiler feedwater pumps) during low-flow operation, minimum flow valves frequently throttle and shut off fluids with extremely high velocity under high pressure differentials. This is widely recognised within the valve industry as one of the most extreme wear conditions. Tungsten carbide seats and stems are virtually the standard solution for withstanding the destructive effects of the combined high pressure differentials, high flow velocities and cavitation erosion.