EMP Automated Tapping Mechanism Improves ... - Pyrotek

September 2010 Volume 4, Issue 3ask the expert...EMP AUTOMATED TAPPING MECHANISMIMPROVES PERFORMANCE IN METAL TRANSFERresultant effect of pumping metal intothe chargewell is that a molten metalpressure head is formed. The level ofpressure head is a function of the depthof metal in the furnace and the rate offlow of the metal into the chargewell.E MPTMTechnologiesJason Midgley,OperationsDirector, EMPTechnologiesThe traditional method of transferringmolten metal from a furnace is throughthe combination of transfer height andgravity. Here, Jason Midgley* respondsto a range of customer questions aboutthe function of the metal transfer systemfrom EMP Technologies, Pyrotek MCR(Melt Circulation & Recovery) Group. Itis explained that this system providesan ideal and efficient solution forinstallations where there is a restrictionin transfer height or space due to theplant layout.Q: When is this automated tappingmechanism required?A: The EMP transfer function can beused to assist transfer of metal into acrucible, holding furnace or castingoperation, where height restrictionsprevent the natural, gravity free-flowof metal. In this application the EMPsystem is used to raise the level withinthe EMP chargewell and dischargemolten metal at an elevated height toovercome these limitations.Q: How does this system differ fromtraditional equipment?A: The initial concept was to use theEMP system as a transfer device inaddition to its normal function ofcirculating the furnace, charging lightgaugescrap and achieving excellentthermal and chemical homogeneity. TheBy controlling the speed of flow intothe chargewell, the pressure head canbe adjusted using the EMP pump, toraise and lower the level of aluminiumin the EMP chargewell. This changein pressure head can be used to allowthe flow of aluminium in conjunctionwith a pneumatically-operated tappingplug and precast tapping hole locatedin the rear of the EMP chargewell. Therate of transfer is achieved through acombination of metal level and thesize of the tapping hole in the EMPchargewell.Q: What is the main purpose of thetransfer mechanism?A: The transfer mechanism enables thesafe transfer of metal with finite controlof the flow rate, so that the only operatorinterface required is to start the transferprocess and replace the ceramic coneon the transfer plug.When the transfer process is complete,the EMP can be placed in the reversedirection, causing the EMP chargewellto empty, and allowing the transfermechanism to be positioned withouta molten metal pressure head present,thus making the process much safer.Q: What are the materials and designsused in the equipment?A: The transfer mechanism can beinstalled on a new EMP systemor retrofitted to an existing EMPequipment installation. The overallsupply of equipment from EMP includesEMP automated tapping system schematic, showingmechanism, chargewell and crucibleRecently installed EMP system operating incustomer’s plant

ask the expert... (continued) by Jason MidgelyEMP AUTOMATED TAPPING MECHANISM IMPROVES PERFORMANCE IN METAL TRANSFERa pneumatic transfer mechanism,installation of a tapping block in theEMP chargewell and modifications tothe EMP PLC and HMI control software,as required.Q: What are the special features andthe process benefits achieved usingthis Pyrotek product?A: Features of the Pyrotek EMP systembring a range of benefits to customerprocess operations, including thefollowing.• The operator can be at a safedistance from the tap-out whilemetal is transferred• Metal flow can be turned on and offefficiently• Metal flow rate is easily controlled• Minimal operator interface• Instantaneous and quiescent metalflow• High flow capability• Pressure head can remove heightrestrictions• Long distance transfers possibleQ: What are the additional advantagesfor the customer?A: The rates of transfer experiencedhave been between 2 and 4 tonnes perminute, while still achieving circulationwithin the furnace and maintaininggood levels of thermal and chemicalhomogeneity during the transferprocess.Pyrotek now has installed over 20systems in melting operations globally,employing the EMP transfer functionwith different variants, all delivering thebenefits to customers as described here.www.pyrotek.info/emp*Jason Midgley is Operations Director, EMPTechnologies, Pyrotek MCR Group, Burtonon-Trent,United Kingdom, with extensive fieldexperience in equipment for molten metalhandling and treatment.