Overhead and jib cranes streamline production at Mining Machinery Developments' factory expansion

Worldwide success has prompted Mining Machinery Developments (MMD) to undertake a multi-million pound factory expansion featuring new cranes from Street Crane Company.  The cranes will speed the manufacture and assembly of MMD's heavy duty mineral sizing equipment.  A mix of overhead travelling and jib cranes provides a flexible system for efficient and reliable lifting, handling and production flow that can be easily adapted to meet future expansion.

Two new bays have been added to MMD's factory for the manufacture of heavy fabrications.  Three 20 tonne overhead cranes in each bay run on full-length freestanding 60 metre gantries.  The cranes will be used for offloading vehicles and advancing product through the various stages of production.  Having adequate cranage in the production area ensures optimum levels of productivity as the highly skilled workforce do not have to wait for cranes to become available.

The cranes are double girder box beam design and feature infra-red anti-collision systems so they can safely operate on the same track.  For heavier lifts of up to 40 tonnes, they may be used in tandem and weight distributed by a spreader beam.

The new bays are also equipped with 10 one-tonne jib cranes, with seven units in one bay and three in the adjoining bay.  Each one supports a workstation manned by two welders or platers.  The slewing jib cranes are attached to the gantry legs with fittings that can be dismantled, enabling the jibs to be readily re-located as production needs change.

Within the original factory buildings, where the sizing machines are assembled, Street has installed two double girder cranes of 50 tonnes and one of 25 tonnes.  One of the larger units has an auxiliary 15 tonne hoist to give greater materials handling flexibility.

The 20 tonne overhead cranes feature hoists from Street's ZX series.  An advanced specification hoist designed for reliability and ease of maintenance, the ZX offers true vertical lift and placement.  The 50 tonne cranes feature custom built hoists from Street's VX series.  These heavy duty hoists also offer vertical lift to safeguard product from lateral movement and assure greater safety.  The one tonne jib cranes all use chain hoists from the company's LX series.

For maximum freedom each overhead crane is operated by radio controlled push button hand held remote.  This allows the operator to choose a working location that maximises personal safety and with best visibility.  A standby push-button pendant is also provided for back up.

Since the installation, MMD has continued to receive orders from mining, quarrying, civil engineering and waste handling companies around the world.  The new facilities and cranes have enabled them to speed throughput, reducing delivery times and improving competitiveness and productivity.