Size ： 1/2”~56”（DN15~DN1400）
Rating ： 150~2500LB（PN16~PN420）
Body Materials ： Carbon Steel, Stainless Steel, Alloy Steel, Duplex Steel
Trim ： Carbon Steel, Stainless Steel, Duplex Steel
End Connection ：RF，BW
Qilong trunnion mounted ball valve is used to cut off or connect the media in various pipelines of Class150 Class2500. The valves made of different materials are suitable for various media such as water, steam, oil, liquefied gas, natural gas,coal gas, nitric acid, oxidizer, urea and etc. The driving modes include manual operation, worm and worm gear transmission,pneumatic operation and electric operation. The connection ends can be flange or butt welding.
A primary positive sealing action of O-rings and a secondary fire-proof graphite gasket assure no leakage in all static body joints.
PRESSURE RELIEF (API 6D, 6.8).
All standard trunnion ball valves shall be provided with self relieving seats allowing automatic body cavity relief exceeding 1,33 times the valve pressure rating at 38°C.
Qilong trunnion mounted ball valves have a drilled and threaded drain connection as per API 6D.
Qilong trunnion mounted ball valves have a threaded vent anti-blow-out valve as per API 6D.
VALVE ENDS (API 6D,6.7).
Standard end flanges shall be furnished in accordance with ASME B16.5 for sizes up to and including DN 600 (NPS 24), except MSS SP-44 for DN 550 (NPS 22) and ASME B16.47 Series A for DN 650 (NPS 26) and larger sizes. Standard welding ends shall conform to ASME B31.8 and ASME B16.25.
SEATS, SEAT INSERTS & SEAT SEALINGS
On request, two other Trunnion mounted valve designs are available:
Bi-directional, twin seats valve (with two seats, both seats are bi-directional). This means valves designed for blocking the fluid in both downstream and upstream directions, with two seats, each sealing in both directions: from the valve ends to the valve body cavity and from the body cavity to the valve ends. This seats design improves the sealing capacity of the valve adding a seating surface in line, but an external safety relief valve is needed to allow the release of the cavity over-pressure.
DOUBLE BLOCK AND BLEED (DBB).
Trunnion mounted ball valve according to API 6D definition: valve with two seating surfaces which, in the closed position, blocks flow from both valve ends when the cavity between the seating surfaces is vented through a bleed connection provided on the body cavity.
UPSTREAM SELF RELIEVING DESIGN.
Uni-directional, twin-seat valve with the upstream seat uni-directional and the downstream seat bi-directional. This combination maintains the sealing capacity of the valve in the event of failure of the upstream seat. In addition, as the upstream seat automatically releases the body cavity over-pressure, no safety relief valve is needed for this purpose