S-3000 INTERNAL DOOR QUICK OPENING CLOSURE
Stark Solutions
The Stark S-3000 Internal Door Quick Opening Closure uses an internal lock ring that slides into the inner side of the hub and expands to latch the door securely in place. Durable actuating components are built to withstand the demands of long-term operation across any orientation, size, or pressure rating.
The closure is fail-safe: even if the lock ring malfunctions, the door stays wedged into the hub for another level of safety. A Pressure Alert Valve is attached to a segment of the lock ring and must be removed before the ring can contract and the door can open, and its design needs no O-ring or metal seal ring. A large cross-section O-ring, or an optional lip seal on select sizes, gives a positive seal with tolerance for minor surface damage over long service.
Available from 6″ through 84″ (DN150 to DN2100) in pressure series 150 through 2500, the closure is certified to ASME B31.3, B31.4, B31.8, CSA Z662 Cat. II, and ASME SEC VIII Div. 1. NACE MR0175-compliant materials and a -50°F to 400°F rating suit sour and wide-temperature service, with load binder assist standard on horizontal sizes 24″ and larger. Its range across sizes, pressures, and orientations makes it Stark’s broadest closure choice.
Typical Applications:
Pipeline pig launcher and receiver access, large-diameter filter and separator vessel access, high-pressure vessel access, offshore installations, and sour (NACE) service.
Key Features
- Internal door, expanding lock ring design
- Diameters 6″ through 84″ (DN150 to DN2100)
- Pressure series 150 to 2500
- Fail-safe wedged-door design
- Large cross-section O-ring
- Optional lip seal (S-3000L) on select sizes
- PAV attached to lock ring, no O-ring needed
- Horizontal or vertical orientation
- ASME B31.3, B31.4, B31.8, CSA Z662 Cat. II certified
- ASME SEC VIII Div. 1, U-Stamp available
- PAV per UG-35 of ASME BPVC VIII Div. 1
- NACE MR0175-compliant material
- -50°F to 400°F (-45°C to 204°C)
- Load binder assist on horizontal 24″ and larger
- External hinge trim option for offshore
- Hydraulic lift option on vertical closures
PERFORMANCE ADVANTAGES
Why the Stark S-3000 Closure Performs Where It Counts
FAIL-SAFE WEDGED DOOR
Even if the lock ring were to malfunction, the door remains wedged into the hub rather than releasing, providing a built-in second line of defense. That fail-safe geometry sets the internal door design apart on high-pressure and critical service.
LOCK RING TIED TO THE PAV
The Pressure Alert Valve is attached to a segment of the lock ring and must be removed before the ring can contract, so the door cannot open until pressure is deliberately checked. The PAV needs no O-ring or metal seal ring, removing a maintenance concern.
BROADEST SIZE AND ORIENTATION RANGE
Spanning 6″ through 84″ in series 150 through 2500, in horizontal or vertical orientation, the S-3000 covers applications the threaded and clamp designs cannot. One closure concept serves the widest span of pipeline and pressure vessel needs.
SEAL THAT TOLERATES WEAR
A large cross-section O-ring, or an optional lip seal, delivers a positive seal while tolerating minor surface damage that would defeat a tighter seal over long service. That keeps the closure sealing reliably through repeated cycles.