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Taper-Lok Pressure Energised Connectors

Welding Units present a smaller, lighter weight bolted connector providing a high integrity seal under extreme conditions.

Taper_Lok 1
Taper-Lok was developed by Bas-Tex/Brown Fintube in the USA, originally for ‘hairpin’ heat exchangers. The Taper-Lok seal is designed to be the safest possible of any mechanical connection. For this reason an area type seal was selected rather than the point seal used in some clamp type connectors.

The area tapered seal allows the flanges to accept up to 2° axial misalignment and still give a full integrity seal. During installation the misalignment capabilities coupled with low pre-stresses allow for easier bolt-up, particularly sub-sea or in other areas with poor accessibility.

Extensive testing has been performed on Taper-Lok Connectors over the years. Separate data sheets are available for these tests, which include:

Taper-Lok 2Taper_Lok 3

  • 10" 900 Weldneck Set - pulsating pressure fatigue test, combined static hydraulic pressure/cyclic bending test, hydrostatic burst test and static hydraulic pressure test.
  • 12" 5,000 Weldneck Set - internal pressure and bending moment test - flanges misaligned.
  • 8" 5,000 Swivel Set -internal N/He leak testing.
  • 8" 5,000 Swivel Set - full API 6FB Pt II Fire & Bend Test
  • 10° Misalignment Flange - internal & external testing

Taper-Lok has an outstanding record of service in the most demanding environments, recently these have included:

  • Phillips 30", 34" & 36" Ekofisk II Export Pipelines
  • Phillips Eldfisk Water Inj’n - Up To 24" NB at 418 Bar
  • BP ETAP Risers - Up to 24" NB 250 Bar at 105 °C
  • Chematur Chemical Treatment - Alloy 625 at 593 °C
  • Eastman Chemical - Hydrogen Reactor Vessels
  • Tested by NASA for Cryogenic Refuelling Systems on the Space Shuttle
  • Approved by the UK H&SE for use in Cellar Deck Area of Risers

A full reference list is available on request.

Taper-Lok is available in many different configurations including:

  • Weldneck Assembly
  • Swivel Assembly
  • 10° Misalignment Assembly
  • Vessel/Heat Exchanger End Closure
  • Manways/Nozzles, Clad & Unclad
  • 90° Elbow Assembly
  • Forged Branch Fittings, Elbows, Crosses, Etc.

For further information on Taper-Lok products, please contact:

Welding Units (UK) Ltd
Mill Lane, Rainford, Merseyside WA11 8LR
Tel. +44 1744 884881
Fax. +44 1744 883302

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