CAD Files

FlexLock Coupling

  • FlexLock permits angular deflection between pipes, allowing for normal pipeline movement such as ground settlement. Long radius curves can also be accommodated, reducing the need for special fittings. FlexLock couplings allow for a total angular deflection of ±6° (±3° for flange adaptors).
  • Cost effective – FlexLock can provide significant cost savings compared to non-locking couplings with a harnessing system.
  • Restrains pressure thrusts without thrust blocks at bends.
  • Convert cut lengths of pipe into flanged pipes - allows use of pipe offcuts.
  • Working Pressure of 16bar on water up to and including DN200 and 10bar for DN250 & DN300. For gas applications a working pressure of 6 bar can be achieved.
  • The ability to provide angular deflection in ANY plane is a particular advantage - a harness assembly can provide angular deflection only in ONE plane.
Pipe Materials
Steel Ductile Iron
Gas Water

1 Suitable for Water & Gas

A FlexLock is supplied as standard with EPDM gaskets for water applications to EN 681. However it is also available with Nitrile gaskets to EN 682 suitable for natural gas, petroleum products, low aromatic fuels, sewage and drainage.

Viking Johnson FlexLockgaskets

2 Excellent Corrosion Protection

Metal components are coated with Rilsan Nylon 11 which is WRAS approved for use with potable water. The nuts and bolts are Sheraplex coated to WIS 4-52-03, offering long term protection against corrosion, impact and abrasion to ensure continued reliable performance.

Viking Johnson FlexLock-Rilsan

3 Unique Load Bearing Teeth

As the compression bolts are tightened, unique load bearing stainless steel teeth, that are moulded into the gasket grip around the outside diameter of the pipe, providing a fully end load restraint joint.

Viking Johnson FlexLock Illus Teeth

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    FlexLock Brochure

    Couplings & flange adaptors for ductile iron or steel pipes


Data Sheets

Fitting Instruction

  • flexlock cover FlexiLock Couplings & Flange Adaptors Installation Manual

General Videos

  • Viking Johnson Multi Million Pound Investment
    Crane BS&U has completed a multi-million pound investment in its Viking Johnson factory at Hitchin that will strengthen its business model to deliver enhanced customer benefits in terms of 'Best in Class' service and products. The investment has supported the creation of an entire linked value stream from the supply of raw materials through to the final manufacture of the products resulting in vastly improved lead times, product availability and plant flexibility.
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