Socket joints for ductile cast iron pipes und fittings Our ductile cast iron pipes and fittings can be supplied with different restrained socket joints. These are basically divided into restrained and non-restrained connections.
The restrained connections are divided into form-locking and friction-locking connections.
Our form-locking connection is the BLS restrained socket joint. BLS stands for “Buderus Lock System”. The English word “Lock” thereby stands for the lock with which the BLS restrained socket joint is locked together by means of the interaction between the preliminary chamber and the welding bead. This high-strength yet easy to install connection is suitable for even the most extreme application cases, allowing operating pressures up to 100 bar, depending on the nominal width. This also means high permissible tensile forces.
Not least for this reason, but also because of their deviation capability of up to 4°, ductile cast iron pipes with the BLS restrained socket joints are also suitable for trenchless installation procedures such as burst lining procedures, horizontal directional drilling, press-pull procedures etc. Further areas of application include, amongst others, snow-making technology, fire-extinguishing pipes (FM approval received), turbine pipes, exposed pipes, inclined pipes etc.
Thanks to the comprehensive range of fittings, and the completion of the BLS system by corresponding valves and flap valves and other specific accessories, this system is also ideal for the complete production of pipe junctions and intersections.
The BLS restrained socket joint is available in the nominal widths DN 80 to DN 1000.
Our friction-locking connection is the BRS restrained socket joint. BRS stands for “Buderus Restrain System”. The restrained locking is, in this case, ensured by the TYTON-SIT-PLUS ring, which can be inserted into every TYTON socket. This means that normal TYTON pipes and fittings can be used for the restrained arrangement of a pipeline.
The BRS restrained socket joint is available in the nominal widths DN 80 to DN 600 (including DN 350). The permissible operating pressure is up to 32 bar, depending on the nominal width. Thanks to the deviation capability of the joint connection of up to 3°, the pipes, at a length of 6 m, can be laid in a curve radius of only 115 m.
These include the TYTON socket joint, the screw-socket joint and the gland-socket joint.
The TYTON socket joint is found in practically every pipe and in most fittings. Proven over decades, it is not immediately apparent what the TYTON socket joint does. Pipe systems with these proven connection joints remain tight even under high internal pressure, maximum decentring and external over-pressure, e.g. from surrounding ground water. This also applies if restrained forces or bending stresses occur due to traffic loads and ground movements.
Acting as a joint, the system follows the ground movements, without transmitting bending stresses to the next pipes or fittings. These properties are achieved thanks to the high form stability of the joints and their special design.
The TYTON socket joint is proof against roots and can withstand high stresses; deviation of the connection by up to 5° is possible, depending on the nominal width.
- with TYTON socket joint to DIN 28 603 (Type A)
DN 80 to DN 600
- with TYTON socket joint to DIN 28 603 (Type B, long socket)
DN 700 to DN 1000
The screw-socket joint and gland-socket joint are found only in some fittings, such as EUor U-pieces.