Serving Canada & the U.S. Since 1986

There is More to Quick-Opening Closures Than Meets the Eye

PS Filter® is now introducing a patented QOC (Quick Opening Closure) option for pipeline and other applications where safe and quick access is required for pressure vessels and pig launchers and receivers. This technology compliments our Filtration Separation equipment to save operational time and exposure to open existing and new pressure vessels for a multitude of process applications.

The QOC Technology can be easily utilized on existing pressure vessels to reduce operational time and costs and ensure operator exposure time to hazardous gases and liquids is dramatically reduced to provide a safer workplace environment.

These QOC’s (Quick Opening Closure) are ASME Code and will have the applicable CRN for respective provinces as required. The Twinlock® Quick Opening Closure will be a real advantage to the Canadian Industry because it is operationally one of the easiest and safest closure on the market and our initial market survey has found it is very competitively priced along with availability to meet tight schedules.

About the Twinlock Quick Opening Closure

Pipeline Equipment Inc’s primary focus is Safety First! Their newer patented technology such as the Pressure Alert Valve (PAV) accompanied by the interlocking double safety mechanism and heavy duty lugs with beveled groove integration correlates to less fatigue factor at all pressure levels in comparison to our competitors closures which have more wear points and older band technology.

Twinlock Quick Opening Closures are manufactured in the USA to meet customer specification and all applicable Code/CRN requirements and available in Canada through PS Filter®


Quick Opening

Pipeline Equipment, Inc. has designed and developed a quick opening closure. This innovative, patented closure system is safe and easy to operate and may be used in a broad range of applications. With more than 15 years of engineering, design and machining experience Pipeline Equipment, Inc. provides closures to meet customer specifications and achieve quick deliveries.

Easy To Operate

Operation of the closure can be accomplished by one person without the use of tools. The integration of the locking segments, locking mechanism and door handle into the door provides a compact and efficient design. To open the door, the handle requires only a quarter turn, which moves the locking segments from their stowed position. The internal components of the locking mechanism are protected by a weather seal and are stainless or plated to protect them from rust and corrosion. The o-ring groove is machined into the door with the hub o-ring seat area recessed to protect the seat during pig launching and receiving. This configuration assures a positive seal when the door is closed and locked.

Integrated Twin Locks

The safe operation of the closure is ensured by a redundant design in which the closure cannot be opened without the removal of the pressure alert valve and the movement of the safety lock. The pressure alert valve also provides the operator an indication of the presence of any residual pressure in the vessel should the operator inadvertently attempt to open the closure prior to all pressure on the vessel being relieved. Additionally, the safety lock mechanism prevents the door handle from being moved to the open position until after the pressure alert valve has been safely removed. The safety lock must also be returned to the locked position in order for the pressure alert valve to be installed.

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  • Nominal Diameter Range: 6" - 60" standard, larger sizes available on request
  • Design Code: ASME VIII, Division 1 & Pressure Piping Codes B31.3, B31.4, & B31.8
  • Orientation: Horizontal, Inclined or Vertical (Hydraulic, Mechanical, Electric)
  • Safety Features: Integrated safety lock and pressure alert valve
  • Pressure Class: 150#, 300#, 600#, 900#, 1500#, 2500#


  • Hub & Door: SA-105, SA-350 LF2, A-694 F48, Triple Certified
  • Pressure Alert Valve: A-316 Stainless Steel
  • Locking Segments: SA-182 F6A CL2
  • 0-Ring: Viton (standard), 8UNA, customer specified


  • Materials: High Yield, Stainless, other available upon request
  • Weld Bevel: Customer specified weld bevel
  • Flanged: Available on request as welded or a one-piece flanged design which eliminates field welds and x-rays
  • Coating: Primer standard, or per customer specification