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Société des Anciens Établissements L.GEISMAR
– Prohibited Reproduction ©
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General information
The TH 70 VLA hydraulic tensioner, easy to install because of the assembly of its various
components by articulation forks and pins, is particularly designed to obtain, through controlled
mechanical traction, the equilibrium (release) of long welded rails (LWR’s). This is achieved by a
mechanical deformation of the rails remaining in the elastic domain. A thermal engine drives the
hydraulic unit that will supply the cylinders.
The TH 70 VLA hydraulic tensioner can also be used for :
reducing gaps during operations of repairing rails or broken welds;
avoiding the removal of bars in the case of replacement of a defective weld that has not
broken or in the case of the creation of a bonded joint on the track;
adjustment of an expansion appliance;
incorporation of appliances.
At any time the traction of thrust force can be modified according to variations in ambient
temperature, and therefore that of the rail, by adjusting the hydraulic pressure.
The traction exerted on the ends of the rails helps to maintain the correct position of the latter
in the horizontal and vertical planes, thus preventing any deformation during the welding
operation and eliminating contraction tensions in the weld.
Thanks to the double-acting cylinders, the hydraulic tensioner can also cancel out the internal
stresses in the rails, thus making it possible to carry out sawing and cutting without risk to the
users, preventing jamming of the tools.
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Using conditions
The thrust force must be limited to 200kN with the use of the arches, because of
their resistance. The use into thrust must always be carried out without using the
rods.
