VERLINDE expands its catalogue with a new range of PDW open winches for heavy applications

PDW now widens VERLINDE's open winch lineup to cover heavy-duty work. Spanning capacities from 6.3 to 70 tonnes with duty classes reaching M6, this range answers a broad set of lifting needs.

Among the technical characteristics standard across the range of VERLINDE PDW open winches are hoist motors equipped as standard with extended speed range (ESR): slow speeds and high torque favour safety when shifting loads, while fast speed in unloaded travel promotes productivity. Trolley drive is regulated with VVF drive for speeds from 20m/min to 61m/min. The trolley, in its double girder or suspended version, is equipped with two travel mechanisms.

Lateral traction across the trolley's transverse axis comes from the compact rope lead-offs, which are simple to handle thanks to their closed-in build and can spin freely through roughly 360 degrees.

The pulleys require less rope lead-off and fewer wire rope turns per cycle, so the lifespan of the high strength steel wire rope is extended. Likewise, rail spacing is designed to optimize the quantity of steel ropes and their dimensions.

Better lifting performance

Mounting the motor via flange rules out misalignment between it and the gear box. Both winch and travel motors use a squirrel-cage design, purpose-built for overhead crane use. A distinctive gear box and lifting drum design keeps the drum and trolley structures from deforming and keeps drum and gearbox aligned, which curbs fatigue breakage and stretches out the equipment's working life.

The modular design of the lifting mechanism gives a compact structure, with rail spacing optimized according to the lift height the application requires. The lifting mechanism is supported by an original floating suspension which eliminates bending forces caused by the weight of the load. A fatigue analysis of the structure has led to an innovative design of the mechanism's support system that eliminates internal stress. As standard, this hoist unit is fitted with an electrohydraulic thruster disc brake whose torque is at least 200% of the rated load.

Extra devices for greater safety

Hook overtravel is blocked by adjustable bottom limit switches that reset automatically. The trolley's transverse travel also gets slow-down and stop functions.

Upward hoisting motion is backed by a safety limit switch that guarantees the top mechanical limit switch works as intended. End carriages come with buffer stops built in.

A load limiter on every winch stops hoisting once the rated load is exceeded, guarding against overloading.

All configurations can optionally add a guard bar that protects the wire rope drum from overlap.

A diagnostic unit also keeps constant watch over the SWP (safe working period) — how long a hoist can safely operate within its duty classification's limits.