Chemical Cryogenic Top Entry ball valve

Chemical Low-Temperature Top-Entry Ball Valve is a specialty control valve designed for chemical cryogenic applications. It combines a top-entry structure, low-temperature corrosion-resistant materials, and precision sealing technology, making it suitable for chemical low-temperature reactions, cryogenic medium transfer, and other demanding environments. It ensures reliable flow control under extreme low temperatures and corrosive conditions, with core advantages including resistance to cold-induced brittle fracture, corrosion and wear resistance, and easy maintenance. It effectively addresses common issues in chemical low-temperature service, such as valve corrosion, seal failure, and difficult maintenance.

Structural design focuses on chemical low-temperature and top-entry adaptability:
The valve body is made of 316L ultra-low carbon stainless steel or Hastelloy C-276, processed with –196 °C cryogenic aging and stress-relief treatments to eliminate internal stresses and prevent brittle fracture and corrosion-induced deformation. The top-entry design allows the core components (ball, seat, stem) to be removed and installed from the top without dismantling the pipeline or valve body, greatly improving maintenance efficiency.

The ball is solid forged and solution-treated, with sealing surfaces overlaid with Stellite 6 or cobalt-based hard alloy (hardness ≥ HRC58), providing excellent resistance to chemical corrosion and wear. The sealing system uses a dual structure of “low-temperature elastic seal + metal backup.” Seats are made of PCTFE or glass-fiber-reinforced PTFE low-temperature corrosion-resistant materials, combined with Inconel alloy spring preloading to automatically compensate for thermal contraction and corrosion wear. Leakage meets ANSI B16.104 Class VI standards.

The stem is made from the same corrosion-resistant material as the body, with nitriding treatment and dual sealing using flexible graphite and PTFE packing, ensuring zero leakage under low-temperature corrosive conditions. Actuation options include manual, electric (low-temperature explosion-proof), and pneumatic drives.

Key technical parameters:

• Nominal sizes: DN15–DN300 (1/2"–12")

• Pressure ratings: PN10–PN250 (Class 150–1500 LB)

• Operating temperature range: –196 °C to –40 °C, suitable for LNG, liquid nitrogen, and low-temperature chemical feedstocks

• Corrosion resistance: Meets NACE MR0175 standard, compatible with pH 1–14 acid/alkaline media and Cl⁻/H₂S-containing corrosive media

• Connections: Flanged (ASME B16.5, GB/T 9113) or butt-welded; sealing surfaces support RF and RTJ types

Manufacturing and testing strictly follow API 6D, ASME B16.34, and GB/T 24925 standards, including cryogenic impact tests, corrosion resistance tests, sealing performance tests, and non-destructive examinations (UT/RT).

Performance advantages:

1. Chemical low-temperature adaptability – corrosion-resistant low-temperature materials enable reliable operation in chemical cryogenic and corrosive conditions.

2. Efficient maintenance – top-entry design allows inspection and maintenance without removing the pipeline, reducing downtime.

3. Reliable sealing – dual sealing system with automatic compensation ensures long-term zero leakage.

Applications: Suitable for chemical cryogenic reactors, low-temperature chemical feedstock transfer, and LNG chemical processes. Typical installations include cryogenic chemical units, low-temperature storage tank outlets, and low-temperature chemical distillation pipelines.