Double-handed lead screws need no lubrication

Abssac can readily supply lead screws in both a right-handed and left-handed thread format. As an example of the type of problem these products can solve, a redesigned food packaging machine was originally using opposing screws to operate a high-speed gripper. This gripper was required for hot plastic foil sealing of ready-to-cook meals destined for a leading supermarket chain. Since the machine operated within a food grade environment, there could be no lubrication with the system, which contributed to the premature failure of the nuts after only 50,000 cycles. It was also a concern that the existing lead accuracy matching between the pair of lead screws could also be a factor in the excessive wear of the nuts.

By utilising a PTFE-impregnated plastic as the antibacklash nut base material, and by ensuring a matched pitch accuracy of the screws in both the right- and left-handed screws, initial tests of up to 56,000 cycles could be completed without any sign of wear to the nuts.

Being able to match the screws' pitch accuracy reduces the stresses within the system considerably, thereby ensuring a more reliable linear movement.