Durable plastic energy chains successfully replace festooning in waste cranes

Profile

• What was needed: plastic energy chains, supplied as a completely pre-fitted readychain system, i.Sense Push/Pull Detection System to prevent failures
• Requirements: high speeds (2.5m/s) and fast accelerations (0.5m/s²) were achieved in the cranes. In addition, a long travel of 116m, a tight bend radius and the presence of moisture and dust placed additional strain on the energy supply. 
• Industry: Cranes
• Success for the customer: by installing two e-chains, the required cable length and cable cross-sections were significantly reduced, resulting in major savings. In addition, the service life increased to 7.5 years for the e-chain and 10 years for the cables.

Problem

MBS is a waste-processing company that operates a facility in Geel where bulky waste is handled by two travelling cranes with scrap grapples. The cranes installed in 2003 were initially equipped with festooning cable systems for the power supply. However, both the festooning cables and the trolleys suffered from the adverse operating conditions, including high speed (2.5m/s), fast acceleration/deceleration (0.5m/s²) and the presence of moisture and dust. In addition, the cables were vulnerable due to the extended length required to cover the 116m travel and the trolleys' tight bend radii. The abrupt accelerations and decelerations also very often caused the festooning system's cable trolleys to collide at high speed.
As a result, the cables and trolleys were often damaged, leading to costly unplanned production downtime. Although several attempts were made to improve the situation, the problem could not be successfully resolved.

Solution

In 2013, the operator MBS commissioned TCS to carry out preventive maintenance on the cranes. They determined that the installed festooning cable system was not suitable for this application. After TCS suggested our e-chains, the operator decided to install two of our 60m long energy supply systems with a floating moving end. This meant that significantly shorter cables could be used (half the track length instead of 1.2 times the track length) and the cable cross-section reduced, which led to major savings. In addition, the service life increased to 7.5 years for the e-chain and 10 years for the cables.By supplying the e-chains as a readychain system, i.e. as a pre-fitted cable guidance system complete with cables, the chain could be installed quickly and without long system downtimes.
Additional safety is also provided by an i.Sense push/pull force measurement, which monitors the entire system and switches off the crane in the event of an overload. This prevents damage to the chain and cables and thus costly failures, reacting to them before they can occur.

In this waste facility, the trolleys of two cranes travel over a length of 116m.

The e-chains installed today enable greater safety at lower costs. Among other things, this was achieved using a push/pull detection system (right side of image).

The trailing cables previously used not only required longer cable lengths and larger diameters, but were also more susceptible to faults due to the high travelling speeds.