Lift, Transport and Reinstall Stuck Manhole Covers with Ease


23. marzo 2016

It takes a lot of muscle power to lift manhole covers out of their frames manually using a hook. Manhole covers may weigh up to 70 kilograms (154 lbs.). Ergonomic considerations make lifting heavy manhole covers a rather risky undertaking. Even if two persons lift the heavy covers, injuries may occur.

The Probst GmbH developed three versions of manhole cover lifters for use as muscle power-saving alternatives to a hook. These lifting aids lighten the work on construction yards and in logistics facilities considerably and increase the efficiency. One hydraulic and two mechanically operated lifters are available. The long cover lifting bar with handle clearly facilitates the use and maneuvering. To lift the cover out of its frame the operator inserts two 'keys' into the two opening in the manhole cover. These keys are then hitched to the lifter hook. The lifter hooks can move continuously in horizontal direction. This allows the step-less adjustment of the connection between manhole cover holes and hooks.

Among the three lifter versions, the hydraulic manhole cover lifter SDH-H features the largest breakout force (1,500 kilograms [3,307 lbs.]). Integrated into the hydraulic lifter is a hydraulic cylinder with manual pump. The operator may adjust the space between the hooks continuously as needed from 260 to 950 mm (10.2 – 37.4''). It takes only a few steps to take the lifter apart. In this transport form, it fits into any rear trunk.

The mechanically operated manhole cover lifter SDH-M-10 is suitable for manhole covers with diameters up to 900 mm (35.4''). Operators may adjust the distance between the hooks continuously between 100 mm and no more than 590 mm (3.9 – 23.2''). Tilting the SDH-M-10 using the lifting bar with handle will lift up the manhole cover.

After several years of remaining in place undisturbed, manhole covers may resist attempts at lifting them. For such covers, the mechanically operated manhole cover lifter SDH-M-10 features foldout legs (lifting spindles). These remain in 'park position' as long as they are not needed. In 'swivel position', the feet are placed on the floor. The operator can now turn a crank lever to push out the stuck manhole cover. Once the manhole cover can move freely, the leg supports are swiveled back into park position.

Alternatively, loosely seated cast steel or gray cast iron covers may be lifted using a magnet. This eliminates the need to adjust the hook distances. For this procedure, the Probst Company offers a shortened hook, which links up to the optional permanent lifting magnet PML-400. The magnet may be turned on or off with a single easy hand movement.

Possibly required special traverses to lift split manhole covers may be installed on the SDH-M-10 lifter.

The SDH-LIGHT lifter is the low-cost 'little brother' in the family of Probst manhole cover lifters. This lifter is particularly light and handy. It weighs only 18 kg (39.7 lbs.). Upon request, we retrofit this manhole cover lifter with a permanent lifting magnet. The SDH-LIGHT lifter is suitable for manhole covers with diameters up to 800 mm (31.5''). Lowering the handles tilts the SDH-LIGHT and the manhole cover is lifted up. As described for the SDH-M-10, special traverses may also be mounted on the SDH-LIGHT for the lifting of split manhole covers.