In Documentary

Lowering in can often cause more challenges than lifting in lifting & lowering applications due to the need to control speed and adhere to maximum safety speed requirements. The speeds for lifting and lowering are generally limited by load-independent flow control valves. So, to enhance efficiency of mobile applications such as agricultural machinery, forklifts, cranes, elevators, etc., lowering functions will generally require a more complex hydraulic circuit to operate at higher speeds while still moving loads evenly and safely.

This more complex circuit can be simplified by including load-independent flow controllers. The optimal choice for these controllers is the all-in-one proportional 2-way flow control cartridges with pressure compensator and a seat function in the normally closed switching position. Hydraquip is proud to partner with Wandlfuh Hydraulics & Electronics to provide this “all-in-one” valve technology.
The “all-in-one” valves from Wandfluh can be applied to ensure machinery will not exceed maximum speeds in any circumstance and ensure good resolution in the range of lower speeds. This resolution can also help to lower loads sensitively as well as pick them up accurately.

The all-in one solution:
– Keeps the load stable with seat tight design in de-energized state.
– Sensitively regulates oil quantity in proportion to the control current.
– Maintains constant lowering speed, independent of the load.
– Simplifies the hydraulic diagram because all-in-one construction combines load holding and speed limiting functions.
– Delivers a compact and cost-efficient system.

Wandfluh offers QSPPU10 valves (UNF10 up to 35 l/min) for smaller solutions and M33 valves (over 100 l/min) for larger solutions. Hydraquip has the technical expertise to help customers apply an all-in-one solution to several different types of applications. Our fluid power certified sales team can help design your circuit to maximize efficiency of your system and enhance the operational safety. Contact us today for assistance with your lifting/lowering applications.