Tianjin Kewote Globe Valves: From materials to processes, interpreting the standards for professiona

Tianjin Covot Globe Valve: From materials to craftsmanship, interpreting professional valve manufacturing standards

In the field of industrial fluid control, the stop valve is the core equipment for cutting off and regulating the medium. Its performance is directly related to the safety, stability and operation efficiency of the system. Tianjin Covot Valve Technology Development Co., Ltd. (hereinafter referred to as"Tianjin Covotel") has been deeply engaged in the manufacture of stop valves for many years.Strict material selection and exquisite craftsmanshipandFull-process quality control system, redefines the manufacturing standards of professional valves and provides reliable and economical fluid control solutions for industries such as petrochemical, municipal engineering, and electric power.

1. Material selection:"Material" as the foundation, laying the foundation for excellent performance

Materials are the foundation of globe valve quality. Tianjin Covot selects a variety of high-quality materials based on different working conditions to ensure valve stability in complex environments such as pressure, temperature, and media corrosion.

1. Main material: adapt to multiple scene requirements

· Carbon Steel (WCB）：Applicable toIt can withstand PN≤32.0MPa, temperature -30~425℃, water, steam, air and other conventional media. It has the characteristics of high strength and moderate cost, and is widely used in municipal heating, industrial pipelines and other fields.

· Stainless steel(304/316）：304 stainless steel is resistant to weak corrosive media (water, steam), and 316 stainless steel has stronger resistance to pitting corrosion due to the addition of Mo element. It is suitable for highly corrosive environments such as chemical industry, seawater, nitric acid, etc., ensuring long-term use without rust and leakage.

· Ductile iron (QT450）: Graphite is made into spherical shape through spheroidization treatment. Its strength and toughness are better than gray cast iron, and its cost is lower than cast steel. It is suitable for low-pressure large-diameter pipelines, such as urban water supply and drainage systems.

· Special alloy material：For high temperature and high pressure working conditions (such as thermal power generation and coal chemical industry), adoptMaterials such as A105 forged steel and chrome-molybdenum steel (WC6) can withstand temperatures up to 550°C and have a compressive strength exceeding 32MPa, meeting the stringent requirements in extreme environments.

2. Seals and valve stems: Durability guaranteed in details

Sealing surface:useCr13 series stainless steel or hard alloy surfacing, with hardness of HRC55 or above, excellent wear resistance, and can maintain good sealing performance after opening and closing more than 10,000 times.

valve stem：Select2Cr13 stainless steel, after tempering and surface nitriding, has its corrosion and bending resistance increased by 40%, avoiding safety accidents caused by valve stem breakage.

2. Process innovation:"Technology" empowers and creates precision quality

Tianjin Covot integrates traditional craftsmanship with modern technology, and embodies professional craftsmanship in every step from design to production to ensure the precision and stability of the stop valve.

1. Structural optimization: balancing efficiency and safety

· Straight-through valve body：The flow path is smooth and the pressure drop loss is lower than that of traditional stop valves15%, improve media conveying efficiency;

· Bellows seal design: Double-layer corrugated pipe+ Double packing seal completely solves the problem of valve stem packing aging and leakage, with zero external leakage rate, in line with international sealing standards (ISO 15848);

· Low torque opening and closing：Rolling bearings are used at the connection between the valve stem and the gate to reduce the opening and closing torque30%, suitable for manual, electric and other driving modes, easy and labor-saving operation.

2. Precision manufacturing: Intelligent production controls details

CNC machining center：The valve body, valve seat and other key components are processed by five-axis linkage, with dimensional accuracy up toIT7 level, ensuring sealing surface fit > 99%;

Welding process: Using argon arc welding to prime+ Arc welding cover, 100% radiographic inspection (RT) after welding, no defects such as pores and cracks, and welding strength reaches more than 90% of the base material;

Surface treatment: The inside and outside of the valve body are electrostatically sprayed with epoxy resin, and the coating thickness is80~120μm, adhesion level 1 (GB/T 9286), salt spray resistance test over 500 hours, suitable for humid, dusty and other harsh environments.

3. Quality control system:"Strict" as the guideline to protect the bottom line of safety

Tianjin Covot has established a full-process quality control system from raw materials to finished products, and ensures that each stop valve meets the standards through layer-by-layer inspections.

1. Raw material inspection: Incoming materials must undergo spectral analysis (detectionCr, Ni, Mo and other element content), tensile test (testing tensile strength and yield strength), unqualified materials will be rejected;
2. Process inspection：Set quality control points for each process, such as valve body water pressure test (1.5 times the nominal pressure for 30 minutes without leakage), valve stem hardness test (HV ≥ 250);
3. Factory inspection：The finished product must pass the air tightness test and opening and closing life test (≥5000 cycles), flow characteristic test, and complete inspection report are attached to ensure "zero defect" factory delivery.

4. Application Scenario: Professional Adaptation to Serve the Needs of Multiple Industries

With excellent materials and craftsmanship, Tianjin Covot stop valves are widely used in:

Municipal Engineering: For urban water supply and heating pipelines, ductile iron stop valves are used, which are resistant to mud and sand wear and have low maintenance costs;

Petrochemical：High temperature and high pressure pipelines use stainless steel or chrome-molybdenum steel stop valves, which are corrosion-resistant and erosion-resistant to ensure production safety;

Food and Medicine：316L stainless steel stop valve, inner wall polishing Ra≤0.8μm, no sanitary dead corners, in line with GMP standards;

Electricity and Energy：Selection of steam system for thermal power plantsA105 forged steel stop valve, resistant to high temperature oxidation, with a service life of over 10 years.

Conclusion: Covotec standards define new heights for professional valves

Tianjin Covot stop valve,With the motto "Material is the root, craftsmanship is the soul, and quality control is the shield," we control every detail from the source, demonstrating the reliability of "Made in China" with professional strength. Whether working in conventional or extreme environments, choosing Covotel means choosing a "durable, safe and efficient" fluid control experience.