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Home News Standardized Manufacturing Process of J-VALVES Workshop | Full Quality Control for DN25~DN80 Class16 WCB Floating Ball Valves
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DN25DN80 16 WCB floating ball valve

The service life and sealing performance of floating ball valves entirely depend on standardized management in manufacturing workshops. The root cause of failures for many low-cost valves lies in simplified casting, hydrostatic testing and coating procedures. Founded in 2009, J-VALVES has built a dedicated complete production workshop for floating ball valves. We have formulated stringent standardized manufacturing procedures for small-bore WCB floating ball valves ranging from DN25 to DN80. Every valve delivered undergoes inspections across 8 core processes. We are one of the few domestic valve manufacturers that realize full in-house production of small-bore cast steel floating ball valves.


I. 8 Standardized Manufacturing Procedures in Workshop (DN25-DN80 Floating Ball Valves)

Combined with on-site photos of mass-produced finished valves in the workshop, the complete production workflow is as follows:

  1. Incoming Inspection of WCB Raw Materials: Spectroscopic analysis of incoming carbon steel raw materials to eliminate blanks with substandard material composition.

  2. Precision Casting of Valve Bodies and Balls: Valve bodies are poured in our self-owned sand casting workshop, followed by annealing to relieve casting stress and prevent valve body cracking under high-pressure working conditions.

  3. CNC Precision Machining: Valve balls are mirror-polished to a surface roughness of Ra0.8; valve seat sealing grooves are milled with high precision to ensure perfect sealing fit.

  4. Non-Destructive Testing of Components: Magnetic particle inspection on valve body surfaces to detect casting defects such as blowholes and cracks.

  5. Assembly of Sealing Components: Standardized assembly of PTFE seats, anti-static springs and fire-safe gaskets; uniform calibration of clearances for floating balls.

  6. Shell Hydrostatic Strength Test: Maintain pressure at 1.5 times the nominal pressure for 5 minutes; shells must show no leakage or deformation.

  7. Valve Seat Air Tightness Test: Gas sealing test at 1.1 times the working pressure; valves can only be warehoused after passing bidirectional zero leakage standards.

  8. Anti-Corrosion Coating & Finished Product Storage: Sandblasting for rust removal, followed by three layers of epoxy paint coating. After air-drying, finished valves are neatly stored on pallets, matching the on-site finished product status shown in workshop photos.

The entire set of procedures is completed in a closed-loop manner within our own workshop, with no outsourced machining links. This eliminates quality degradation caused by cost-cutting in outsourced processes.


II. Core Advantages of J-VALVES Workshop Manufacturing vs. Conventional Industry Manufacturers

  1. No Outsourced Procedures: Casting, machining, pressure testing and coating are all completed in-house with full-process production monitoring. Customers may arrange on-site factory audits at any time.

  2. Unified Pressure Testing Standards for All Sizes:Floating ball valves of all DN25 to DN80 specifications follow identical pressure inspection standards; no simplified testing for small-bore models.

  3. Batch Sample Retention Mechanism for Finished Products: Samples are retained long-term for every production batch, enabling rapid traceability of production lots in case of on-site operational issues.

  4. Dedicated In-House QC Team: An independent quality inspection department separate from the production line. Non-conforming valves are sent for rework directly to prevent defective products from entering the market.

  5. Flexible Production Lines: Simultaneous mass production of standard, fire-safe and anti-static floating ball valves with no lengthy downtime for production switching.


III. Successful Industry Application Cases (Long-term Partnerships Built on Workshop Standardized QC)

Case 1: Annual Framework Procurement with a Large Coal Chemical Group

A leading domestic coal chemical enterprise signed an annual framework agreement, with a stable monthly procurement volume of 500 DN32/DN65 WCB floating ball valves. The client visited the J-VALVES production workshop multiple times to observe the full casting and pressure testing processes, and recognized our standardized QC system. We have maintained stable cooperation for 3 consecutive years with zero batch quality complaints.

Case 2: Long-term Export Partnership with Australian Water Treatment Clients

Australian water treatment enterprises purchase 700–1,000 DN25-DN80 floating ball valves annually. Local importers require full production footage and batch test reports from the factory. J-VALVES provides complete video records of the whole manufacturing process, and all products pass re-inspection by local Australian pressure certification authorities. Our cooperation has lasted over 5 years.

Case 3: Urgent Short-cycle Order for Industrial Park Heat Transformation Project

An industrial park heat renovation project had an urgent demand for 600 DN50/DN80 floating ball valves with a tight 20-day delivery schedule. The workshop launched an expedited dedicated production line to complete full casting, machining and pressure testing via overtime work, delivering all valves on schedule. Random on-site pressure testing of all finished valves achieved first-pass qualification with zero rework.


IV. Sourcing & Procurement Recommendations

When purchasing DN25~DN80 Class16 WCB floating ball valves, prioritize original manufacturers with complete self-owned production workshops. Such suppliers support on-site factory audits, full manufacturing traceability and verification of pressure test records.

J-VALVES opens workshop viewing passages for visitors. Domestic and international purchasers and general engineering contractors are welcome to inspect our mass production line for DN25-DN80 floating ball valves. We offer sample pressure testing and one-on-one technical consultation for customized solutions.


Conclusion

Standardized in-house manufacturing and full-process quality control constitute the core competitiveness behind the stable durability of J-VALVES WCB floating ball valves. For Class16 floating ball valves with small bore sizes DN25 to DN80 used in industrial pipelines, we continuously optimize workshop production techniques to balance high-volume fast delivery and strict quality benchmarks, supplying highly reliable cast steel floating ball valves for fluid control projects worldwide.

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Nominal Size: 1 inch / DN25, range 1/4 to 12 inch Pressure Class: ASME Class 150, 19.6 bar at 38°C; Class 300 optional Body Material: ASTM B148 C95800 nickel aluminum bronze Body Type: Two piece, bolted Ball: C95800, SS316 hard faced optional Stem: C95800 or SS316, blowout proof Seat: PTFE, RPTFE, PPL, or reinforced PTFE Packing: PTFE or graphite combined packing End Connection: Threaded NPT / BSPT, flanged RF to ASME B16.5 optional Service Temperature: -29°C to +150°C standard, +200°C high temperature version Seawater Velocity Limit: About 6 m/s clean, 4.5 m/s with sand Design Standard: API 608, ASME B16.34 Test Standard: API 598, ISO 5208 Operation: Lever standard, pneumatic or electric optional
Size Range: 2 to 56 inch (DN50 to DN1400) Pressure Class: ASME Class 150 to 2500 / PN20 to PN420 Body Material: WCB, LCB, CF8, CF8M, CF3M, duplex, alloy steel Ball: Stainless with hard chrome, ENP, Stellite or tungsten carbide overlay Seat: PTFE, RPTFE, PPL, or metal Stellite faced Seat Arrangement: SPE, DPE (DIB-1), or combination (DIB-2) Packing: Live loaded graphite, ISO 15848-1 qualified Fire Test: API 607, also API 6FA and ISO 10497 Fugitive Emission: ISO 15848-1 class B or A, with temperature and cycle class stated Face to Face: ASME B16.10 short or long pattern End Connection: Flanged RF / RTJ to B16.5 and B16.47, butt weld to B16.25 Features: Double block and bleed, sealant injection, anti-static, anti-blowout stem Design Standard: API 6D, API 608, ASME B16.34, ISO 14313 Operation: Lever, gear, pneumatic, electric, hydraulic, gas over oil Sour Service: NACE MR0175 available
Nominal Size: 1-1/2 inch / DN40 Pressure Rating: 1000 WOG (68.9 bar cold working, non-shock) Body Type: Three piece, bolted end caps, four body bolts Body Material: ASTM A351 CF8 (304), CF8M (316) optional Ball: CF8, polished Ra 0.4 µm, full or reduced bore Seat: PTFE, RPTFE, PPL, or Stellite faced metal Body Gasket: PTFE to 180°C, graphite above Packing: PTFE V-ring to 200°C, graphite above End Connection: NPT, BSP, socket weld B16.11, butt weld B16.25, flanged RF Actuator Mounting: ISO 5211 F05 / F07 pad Air Supply: 0.4 to 0.7 MPa clean dry air Service Temperature: -29°C to +260°C, seat dependent Design Reference: MSS SP-110 general purpose, ASME B16.34 body wall Test Standard: API 598, ISO 5208
Nominal Size: 3/4 x 1/2 inch (DN20 x DN15), reduced bore Pressure Class: ASME Class 600 / PN100, 102.1 bar at 38°C Body Material: ASTM A182 F51 forged duplex, UNS S31803 PREN: Approximately 35 Ball: F51 with HVOF tungsten carbide or Stellite overlay Stem: F51, SS316 or 17-4PH, blowout proof Seat: RPTFE, Devlon, PEEK, or Stellite faced metal Bolting: B8M Class 2, alloy 718, or B7M for sour service End Connection: NPT, BSP, socket weld ASME B16.11, butt weld ASME B16.25 Bleed Port: Cavity bleed with plug or needle valve, lockable option Service Temperature: -29°C to +300°C, seat dependent Design Standard: API 6D, API 608, ASME B16.34 Test Standard: API 598, ISO 5208, cavity test through bleed port Sour Service: NACE MR0175 available