Crane & Monorail System in Modern Foundries
Overhead crane and monorail systems have been used in foundries for many years to handle hot metal, molds, scrap, furnace charges, casting cooling and finished castings. With the advances and reliability of today's crane and monorail controls, automating some of the repetitive operations in foundry applications is becoming more favorable.
Operator fatigue is a critical concern when moving loads of hot metal. Continuous, repetitive moves increase the likelihood of fatigue, resulting in safety concerns for the operator, equipment and other personnel.
Automate the repetitive travel functions of crane or monorail systems that deliver material from single or multiple points to one or more locations in order to achieve a more productive and safer workplace. Installing Electromotive IMPULSE® AFD controls on the crane travel motions can optimize travel speeds and control. Also, radio remote controls allow the operator to safely control the crane equipment.
By incorporating automation, foundries can be more effective workplaces with improved safety by keeping workers away from hazardous areas. Such automated systems also increase worker productivity and improve overall material throughput through optimization of the production processes. When a crane or monorail system is automated, the system becomes more like a process tool than a material handling device. Wear and tear of the mechanical components is reduced due to the use of AFD's, and maximum production throughput is obtained. Following are two examples: 1) An automated crane and monorail system delivers scrap from an enclosed scrap yard to three induction melting furnaces and 2) an auto dispatch monorail carrier delivers hot metal between melt furnaces and a pouring line.
Furnace Charging System
The facility includes three new induction melting furnaces with an enclosed scrap yard. An overhead cab operated magnet crane transports the scrap to bins. The scrap is then dumped into a charge bucket which will be carried by one of two automated monorail carriers to one of the three furnaces. The charge bucket is automatically dumped and the empty bucket is returned to the scrap drier by the monorail carrier.
A PLC in the control room provides the necessary controls for automatic operation, interlocks, carrier routing, carrier anti-collision and personnel safety. The carriers are provided with travel alarms and warning lights. Manual control from a remote radio system is also available.
Hot Metal Delivery Monorail
A monorail carrier delivers hot metal from one of three melt furnaces to one of two pouring stations. The cycle begins by manually filling the hot metal carrier at one of three melt furnaces. The furnace operator manually moves the hot metal carrier to an intermediate treatment station. After treatment, the operator automatically dispatches the carrier to a pouring station where the pouring station operator manually unloads the ladle. Upon completion, the operator selects one of the three melt furnaces and automatically dispatches the carrier to the selected furnace. The hot metal carrier travels to the selected furnace where the cycle is repeated. A PLC mounted on the carrier controls the automatic operation. The carrier is provided with warning lights and travel alarms during automatic travel. IMPULSE® AFD's provide control to prevent sudden acceleration or deceleration of the moving load.