Core Value and Dimension Types of Quick Opening Closures
2026-03-20 09:13In industrial fields such as oil and gas, chemical engineering, and energy engineering, pressure vessels and pressure pipelines are critical equipment for guaranteeing medium transportation and production operations. The switching efficiency, sealing stability, and operational safety of the sealing structures at the equipment end directly affect the continuous operation of production lines, personnel safety during operations, and overall production management in the plant.
The quick opening closure is a pressure-resistant sealing device used instead of traditional bolt flanges, featuring critical characteristics such as safety interlock protection and rapid switching. Compared with conventional flange connections, this solution has clear advantages in improving safety, improving maintenance efficiency, and lowering long-term operational and maintenance costs. It has become an essential key part in pressure systems.
This article mainly covers the core value, common specifications, and applications of quick opening closures. Next time we will share operational standards and industry development trends.
What are the core values of Quick-Open closure?
First point: Higher safety
Traditional flanges need to be taken apart and put back together during switching processes, and all of this is done by hand. Not having specialized safety protection and interlock mechanisms raises risks like operating under pressure, seal failure, and sealing surface damage. In serious situations, this may lead to leaks or explosions.
The quick-opening closure combines multiple safety structures like pressure interlock locking and lock status confirmation. When residual pressure exists inside the equipment, the locking mechanism locks automatically, preventing commiseration structurally. Along with a high-performance sealing system, it works with various complex working conditions and media, meeting all the safety requirements of pressure vessels both domestically and internationally.
Second point: Lower overall utilization cost
Traditional flanges greatly lengthen downtime, reduce production efficiency, and increase operational costs when frequent maintenance is needed. The quick-opening closure uses a lightweight and easy-to-use design, so one operator can finish the whole process of opening, closing, and locking within a short time. This helps shorten equipment maintenance downtime and reduce labor and material costs.
What are the common specifications and applicable ranges of quick-opening closures?
Table 1: Core Parameters and Application Scenarios
Item | Details |
Nominal Diameter DN | Standard range: DN50~DN1400, customization: DN1600~DN2200 |
Nominal Pressure PN/Class | PN10~PN400, Class 150~Class 2500 |
Operating Temperature | Standard: -40℃~120℃, low-temperature type up to -50℃, special high-temperature type up to 230℃ |
Main Material | 16MnIII,SA105N,SA266,SA350,A694F60/65/70 , A182 F304,F316L ,F52,Alloy 625 |
Main Applications | Oil & Gas: Pig launcher/receiver, filter separator, gathering and transportation . Chemical industry: reactors, heat changeovers, distillation equipment Power: Boiler auxiliary equipment, water treatment filters Food and Pharmaceutical: Autoclaves, Fermentation Tanks, Sterile Filtration Devices Others: Nuclear power auxiliary equipment, environmental protection treatment, coal chemical industry, LNG storage and transportation systems, etc. |
Table 2: Matching Table of Diameter-Pressure-Scenario-Frequently Used Structures
Nominal Diameter + Pressure Range | Application Scenarios | Common Structure Types |
DN50~DN300 / PN10~PN40 DN50~DN300 / PN10~PN40 | Small filters, precision tanks, laboratory test devices, small process pipelines | Thread type, bayonet type ,Socket type,quick-opening structure |
DN350~DN1400 / PN16~PN100 DN350~DN1400 / PN16~PN100 | Conventional pig sending/receiving barrels, oil-gas separators, industrial main pipelines, medium tank equipment | Lock ring type, clamp type quick-opening closure |
DN1600~DN2200 / PN40~PN100 DN1600~DN2200 / PN40~PN100 | Long-distance oil & gas pipelines, large industrial storage tanks, special high-pressure reaction equipment, large-diameter process systems | Large-diameter double lock ring type; Triple clamp type ; Electric actuated QOC; Electro-hydraulic actuated QOC; customized reinforced structure |
That's all for today's sharing. If you have any questions about quick-opening closures or customizing sizes, just leave a message. You can also click this link to explore our previous posts（clamp-type-quick-opening-closure）.
Next time, we'll talk about the operational guidelines and industry trends of quick-opening closures.