FLOWTITE Couplings and joints

The majority of buried Flowtite pipe-lines are assembled with the trusted Flowtite Double Bell Coupling. They have been used on all continents of the world since 1979.


Installation of a Flowtite Double Bell Coupling. The small cloth underneath the coupling is preventing gravel from the pipe bed entering into the coupling as it is assembled - a quick way to make a secure coupling assembly.

The expected lifetime of Flowtite Couplings is more than 150 years. Therefore, the Double Bell Coupling is a preferred coupling for the majority Flowtite installations. The Double Bell Coupling comes in four different versions: (1) Standard Pressure, (2) Sewer, (3) Biaxial Lockjoint and (4) Angled Coupling.

Technical data
Flowtite double bell coupling

Operating pressure*: Up to 32 bar

Main materials: Resin, glassfibre, sand

Estimated lifetime: More than 150 years

External waterhead: 50 meter +

Operating temperature: -50°C - +50°C

Estimated gasket lifetime: 150 years

Gasket: Reka


Cross section of a Flowtite Pressure Coupling as it will appear before pressure is applied in the pipeline. The Reka gaskets are seen in black. The center gaskets is protecting the spigot ends.


Cross section of a Flowtite Pressure Coupling after pressure is applied in the pipeline. The Reka gaskets is compressed towards the coupling wall.


Flowtite Flanges
Flowtite manufacture and sell flanges in different designs and according to different standards and requirements. When connecting two GRP flanges over 300 mm in diameter, only one flange will have a gasket groove in the face. The standard bolt pattern to which flanges are manufacuted is ISO2084. Other bolting dimension systems such as AWWA, ANSI, DIN and JIS can be supplied.


Close up of a Flowtite flange.

Butt-Wrap Joints
Flowtite pipes may be joint using glass fibre reinforce-ment and resin. The butt-wrap joints are common in applications with axial thrust. Flowtite provides the necessary instructions for butt-wrap joining according to Flowtites patented butt-wrap technology. This patented technology provides faster and more cost efficient installation.


DN 4000 Flowtite pipes with butt-wrap joints in Jubail, Saudi Arabia.

Using Steel Couplings to Join Flowtite Pipes
Flowtite pipes can be joined using steel couplings. Examples of steel couplings are the tangential bolt couplings of Straub, Tee-Kay and Arpol, and the axial bolt couplings of Viking Johnson, Helden and Klamflex.


Steel couplings on Flowtite pipes at Fall hydropower plant in Norway.