BoWex® GT curved-tooth gear coupling® for processing pumps

Easy to assemble, able to compensate for high displacements and free from restoring forces
On the occasion of the ACHEMA KTR Rheine had introduced the new BoWex® GT curved-tooth gear coupling® for processing pumps for the first time worldwide the predecessor product of which has been used in drive technology for several decades. The coupling which has proven its worth in the chemical industry in many cases was designed for a shaft diameter up to 38 mm.

The ability to compensate for misalignment which is frequently requested for the rough industrial operation is not only preserved by the double-cardanic operating principle, but even increased. The curved-tooth gear coupling® allows for the requested positive-locking torque transmission both with axial, radial and angular shaft misalignment. The reason is the curved tooth preventing edge pressure with angular/radial displacement. The large contact surface bet-ween hub spline and sleeve and the material combination of steel hub with nylon sleeve are the secret of the optimum characteristics with wear.

The BoWex® M coupling allows as a standard a very short shaft distance dimension of 4 mm, the hub splines being close to each other. For each hub an angular displacement of a maximum of 1° per bending level, i. e. per each hub, is admitted. Since the hubs of BoWex® GT are simply assembled upside down, the distance between the hub splines grows. This amendment in geometry allows for a significantly higher radial displacement of about 0.95 mm, again with an angular displacement of 1° per hub. Compared to the usual flexible coupling systems this corresponds to a three times bigger ability to compensate for displacements.

The double-cardanic BoWex® GT does not only reliably compensate for the displacements that arise, but it does not produce any restoring forces either. The coupling operates without any constraints with radial displacement, in this way minimising the load on bearings and seals particularly on the pump. Below the line this has a positive effect on the balance of the life cycle cost of the pump system.

In order to further simplify the assembly of the BoWex® GT coupling, the coupling sleeve was separated into two absolutely identical semi shells. Having unscrewed four screws, these can be disassembled easily and quickly without having to shift motor or pump. The new sleeves are made of fibre-reinforced nylon materials. In this way BoWex® GT is in accordance with the requirements of ATEX as well. The time which a preventive maintenance of the coupling takes can therefore be reduced to a minimum. It is possible to retrofit older types of BoWex® couplings which have already been installed with the split sleeves, too. KTR is in a position to issue a corresponding certificate of conformity for existing pump systems according to a process certified by Bureau Veritas.