Introduction to Wear-Resistant & Corrosion-Resistant Ceramic Valves

Under harsh working conditions in chemical, coal and petroleum industries, traditional metal valves are increasingly unable to meet the requirements of heavy-wear and strong-corrosion service. Common pain points include easy leakage, high operating torque and poor corrosion resistance of sealing surfaces. To break through performance bottlenecks, metal valves require comprehensive innovation in materials, structural design and manufacturing processes. Applying high-performance structural ceramics to industrial valves is a highly valuable technical innovation for the valve industry.

Ceramic valves adopt high-performance structural ceramics for core flow-passing and sealing components. The material features excellent self-cleaning properties, ultra-strong wear resistance, strong corrosion resistance and good self-lubrication, delivering long service life and a wide applicable working-condition range. It is especially suited for demanding corrosive medium transfer scenarios across chemical industries.

Metal valves have a history of more than a hundred years of application. Even with continuous optimization of structures and materials, inherent limitations of metal materials still lead to short service life and serious leakage under heavy-wear and strong-corrosion conditions, directly affecting stable operation of the whole piping system.

Ceramic materials feature extremely low deformation and far higher mechanical strength than metals. Small ionic radius, high ionic valence and large coordination number of ceramic crystals endow the material with extremely high tensile and compressive strength, elastic modulus and hardness. However, inherent brittleness and machining difficulty of ceramics once restricted large-scale engineering application. Over the past decade or so, with continuous iteration and upgrading of martensitic transformation toughening, composite material technology and nano-ceramic technology, the brittleness issue of ceramics has been significantly improved. Toughness and strength have been greatly enhanced, and application scenarios continue to expand. In recent years, the application of new ceramic materials in petroleum, chemical and machinery industries has grown rapidly. Replacing metal components with wear-resistant and corrosion-resistant ceramic parts has become an important development direction of the high-tech new-material industry.

Core Features of Ceramic Valves

Ceramic valves greatly improve flow capacity and sealing performance of industrial piping systems, enhance safety and stability of the whole equipment and help enterprises achieve environmental protection and energy saving. Structural ceramic materials feature low deformation and outstanding tensile, compressive and hardness indicators. With continuous technological innovation, ceramic valves have gained wide recognition from domestic and international industries. Their application keeps expanding, and they belong to national key-supported new-material science and technology projects.

• Ceramic valves adopt new high-tech structural ceramics for sealing and wearing parts, significantly improving wear resistance, corrosion resistance and sealing performance and greatly extending overall valve service life.
• Using ceramic valves reduces maintenance and replacement frequency, ensures stable and safe operation of equipment systems and lowers equipment maintenance costs.
• Ceramic valves effectively improve sealing of industrial pipelines, minimize medium leakage, reduce pollutant discharge and protect the ecological environment.
• Ceramic raw materials are abundant and readily available. High-performance ceramic materials can be produced from common elements such as aluminum, carbon and silicon, saving large amounts of metal and scarce mineral resources.

Wear-resistant and corrosion-resistant ceramic valves are widely used in power generation, petroleum, chemical, metallurgy, mining, wastewater treatment and other industrial sectors. Under harsh working conditions involving heavy wear, strong corrosion, high temperature and high pressure, ceramic valves show particularly prominent advantages with ultra-long service life and better overall cost-performance than various metal valves. As ceramic powder formulation, forming, precision machining and assembly processes become increasingly mature, ceramic valves have won general recognition among valve industry practitioners. Mature application experience of ceramic components can also be extended to more engineering fields.

Introduction to Fully-Lined Hard-Seal Ceramic Valves

• Valve shell wall thickness exceeds requirements of national standard GB, industry standard JB and American standard ANSI. Chemical composition and mechanical properties of main body materials comply with national specifications. Three-section shell design ensures stable structure and simple appearance.
• Valve stem material meets composition requirements. After precision grinding, the stem surface receives anti-corrosion nitriding or quenching and tempering treatment to ensure excellent mechanical performance and corrosion resistance.
• Built-in buffer compensation elastic washers ensure sustained stable sealing. When medium contains solid impurities, jamming is less likely, avoiding ball breakage.
• For fully-lined hard-seal ceramic ball valves, all medium-contacting parts are made of structural ceramic materials. Ceramics feature excellent chemical stability, hardness up to HRA88 or above (second only to diamond), high compressive strength, wear resistance, erosion resistance, oxidation and corrosion resistance, high-temperature resistance and excellent thermal insulation.
• Manufactured with precision lapping processes and high-end processing equipment. The valve features simple structure, smooth flow passage and low medium flow resistance. Hard-seal ceramic internals are designed with six optimized components. Ball and seat are precisely paired and lapped. Inner and outer R faces of ball and seat fit tightly, delivering high ball roundness precision and good surface quality, with low opening/closing torque, low resistance and zero-leakage sealing.

Application Fields of Wear-Resistant & Corrosion-Resistant Ceramic Valves

Thermal power plants, steel, petroleum, chemical, paper-making, bioengineering and other industries. Suitable for boiler steam, lime slurry, seawater conveying with particles, high-hardness particle media, corrosive media with solid particles, powder conveying, flue-gas desulfurization, ash and slag discharge, and feed-water treatment scenarios. Ceramic materials can be changed according to working conditions to adapt to different temperatures and various media.

Executive Standards for Ceramic Valves

Current industry standard for ceramic sealing valves: JB/T 10529-2020 (replacing the old version JB/T10529-2005)

• Design and manufacturing standards: API 6D-2008, API 608-2002
• Face-to-face dimension standards: GB/T 12221-2005, ANSI B16.10
• Connection flange standards: GB/T 9113, ANSI B16.5
• Pressure-temperature ratings: GB/T 12224-2005, ASME B16.34-2004
• Test and inspection standards: GB/T 13927-2008, API 598

Product Classification of Ceramic Valves

Ceramic ball valves, ceramic gate valves, ceramic butterfly valves, ceramic check valves, ceramic slag discharge valves, ceramic rotary valves, ceramic discharge valves, ceramic dome valves, ceramic control valves, ceramic globe valves, ceramic dry-ash valves, pneumatic thin-type ceramic knife gate valves, ceramic bidirectional-flow gate valves, ceramic knife gate valves, ceramic single-disc gate valves, wear-resistant check valves, pneumatic wear-resistant ball-top globe valves, cast-stone wear-resistant ball-type three-way diverting valves, cast-stone wear-resistant ball valves, etc.

Methods to Extend Ceramic Valve Service Life

1. Clean Pipelines to Extend Service Life

Residual welding slag, rust, solidified lime slag, iron wire, cloth scraps and other debris inside piping systems can easily jam in throttling ports and guiding positions, causing pipeline blockage, valve jamming or valve core breakage. Such failures mostly occur after new system commissioning or major equipment overhaul.

When such failures occur, disassemble the valve for cleaning and impurity removal. If sealing surfaces are damaged, perform lapping repair and open the bottom plug to flush pipeline residue. Before system commissioning, fully open the ceramic regulating ball valve to let medium circulate for a period, then switch to normal working opening.

2. Start with Large Opening Operation to Extend Life

For initial commissioning of ceramic regulating valves, it is recommended to run at 80% large opening. After pipeline impurities are flushed away by medium, reduce opening to slightly above normal working opening. As medium erosion gradually consumes the valve core, progressively reduce opening to achieve uniform wear across the core, making full use of the core until its root and sealing surface are damaged.

3. Reasonably Increase Valve Bore to Reduce Erosion

Based on CV value calculation formula, accurately calculate CV value and select matching valve bore. Under the same flow rate, smaller valve bore results in higher medium velocity and more severe erosion on valve core and sealing components. Within allowable regulating-stroke range, appropriately enlarging valve bore can reduce medium velocity and alleviate wear.

4. Shift Medium Erosion Position to Extend Life

In ceramic regulating ball valves, the highest flow velocity and most severe erosion occur directly below the fluid inlet. The ball core of three-piece ceramic ball valves supports reverse installation. One ball core can be re-installed in 4 orientations to transfer erosion positions to non-critical areas, protecting sealing and throttling surfaces and increasing valve life by up to 4 times.

5. Optimize Valve Structure Selection to Extend Life

Prioritize three-piece ceramic regulating ball valves with dual-seat double-sealing structure. During type selection, give priority to products with inclined transition flow passages to reduce fluid impact, minimize medium erosion on ceramic components and extend valve service life.

Shenzhen Juchang Precision focuses on R&D and manufacturing of various ceramic valves, ceramic plunger pumps and other precision ceramic fluid components. Leveraging zirconia and alumina advanced ceramic forming and precision lapping processes, our wear-resistant and corrosion-resistant products suit harsh conditions in lithium-battery, pharmaceutical, chemical and desulfurization industries, and we provide localized precision ceramic fluid solutions.