While many of the cranes we design and manufacture end up in internal warehouse or factory locations, we also produce a number of lifting systems every year for external environments.
Here we take a look back a project we carried out in 2014 for London Underground Ltd. involving two outdoor overhead cranes featuring a special tandem travel positioning sensor system.
Outdoor overhead cranes
London Underground Ltd. approached various suppliers to replace two overhead cranes on an existing outdoor gantry framework at their Ruislip Depot. Pelloby’s design for the dual ten tonne capacity cranes was eventually selected and production began on with Pelloby providing project management support at all stages of the process.
Each crane bridge when installed on top of the gantry offered a 7.1 metre height of lift and a considerable 26.3 metre span. A Verlinde VT low headroom hoist unit was attached to either beam with hoisting motion, hoist travel and the crane long travel all operated from a remote joystick radio control.
Additional features were incorporated into the design to ensure these outdoor overhead cranes were well suited to their external environments. A storm anchor system at the foot of each end carriage wheel base provided extra stability during adverse weather conditions and a special canopy was fitted to the drive motors to protection from the elements.
Tandem travel positioning sensors
In addition to a laser anti-collision system that helped ensure the cranes’ end carriages avoided contact with one another by shutting down the power if they entered pre-determinable distance of each other, these outdoor overhead cranes also featured special tandem travel positioning sensors.
This system also made use of laser technology by measuring the distance between the two crane beams and ensuring it remains constant at all times during tandem lifts where both cranes were being used to handle a single load. Keeping this distance the same maximises stability and ensures the load is evenly supported by both cranes so neither is exceeding its safe working capacity. The system also coordinates the cross travel motion of the hoists along the beams to ensure the load is always lifted as securely as possible.
Have an outdoor overhead crane requirement at your workplace? Or want to find out more about tandem travel positioning sensors? Get in touch on 01952 586 626 or email sales@pelloby.com.
