How does the manual stroke adjustment of the drive units work?

Some of the drive unit types introduced are capable of providing adjustable stroke lengths, i.e. various amplitudes of reciprocating movement towards the pump head. The process of stroke adjustment is operated in various ways depending on the requirements of the user.

Figure 1: Examples of manual stroke adjustments

Stroke adjustment through the direct, manual intervention by operating personnel at the pump on site is the most common standard solution. Depending on the size of the pump and on the mechanical adjustment principle, a certain torque is required for actuation, which is transmitted using turning knobs or hand-wheels with crank handle. Figure 1 shows design variants of manual stroke adjustments.