What is the difference between a trunnion ball valve and a floating ball valve?
A trunnion ball valve has the ball fixed by upper and lower trunnion supports, making it suitable for DN150+ and Class 600+ high-pressure applications with significantly lower operating torque. A floating ball valve lets the ball float freely, pressing against the downstream seat — it achieves bubble-tight shut-off but is best for DN15–DN250 at Class 150–1500 due to higher seat loading at large sizes and high pressures.
What certifications do TANGGONG ball valves carry?
TANGGONG ball valves are manufactured under ISO 9001:2015 quality management, certified to API 6D (pipeline valves), API 607 (fire-safe), CE (EU Pressure Equipment Directive), TUV, and SGS. Third-party inspection by Lloyd's, DNV, BV, ABS, TUV, or SGS is available for specific projects.
Can TANGGONG supply ball valves for LNG and cryogenic service?
Yes. TANGGONG manufactures extended bonnet cryogenic ball valves for service temperatures down to -196°C, suitable for LNG terminals, liquid nitrogen, liquid oxygen and ethylene service. These are tested per BS 6364 cryogenic valve standard and use austenitic stainless steel body with PEEK or metal seats.
What is a full welded ball valve and when is it used?
A full welded ball valve has a completely welded body with no bolted flanges or threaded connections, eliminating all external leakage paths. It is used for buried natural gas and oil pipelines where maintenance access is impossible and zero leakage is critical over 30+ years. TANGGONG full welded ball valves comply with API 6D and GB/T 19672 and can be installed directly underground with cathodic protection coatings.
What sizes and pressure classes are available?
TANGGONG ball valves are available from DN15 (½") to DN2000 (80") in diameter, and from Class 150 (PN20, approx. 20 bar) to Class 2500 (PN420, approx. 420 bar) in pressure rating. Custom sizes, flanges, and materials can be manufactured to customer specifications. Contact our engineering team with your datasheet for a quotation.
How do I select the right ball valve for my application?
Key selection criteria include: (1) pipe size and pressure rating, (2) fluid type and temperature (corrosive, abrasive, cryogenic, high-temp), (3) required shut-off class (Leakage Class A/B/C/D/E per ISO 5208), (4) actuation requirements (manual, electric, pneumatic), and (5) applicable standards and certifications. TANGGONG's engineering team provides free valve selection consulting — contact us with your line conditions and we will recommend the optimal model.
