Barrel Heaters - Hasmak.com.tr

<strong>Barrel</strong> <strong>Heaters</strong>Case HistoryDJ/Nypro Energy AssessmentProblem:DJ/Nypro, a Louisville, Kentuckyinjection molder, needed to increaseenergy savings and reduce operationalcosts during production. The<strong>com</strong>pany used a 750-ton Toshibainjection molding machine and wasseeking a more efficient heatingsolution than their current mica bandheaters.Solution:Watlow’s MI Band heaters provideexceptional heat transfer, high wattdensities and prolonged heater life.To prove their efficiency, Watlowperformed an energy assessment ofthe MI band heaters in <strong>com</strong>parisonto DJ/Nypro’s mica heaters. Bothheaters received resistance tests toinsure that they had the same voltsand watts. For simplicity, calculationswere based on a 24-hour-aday,7-day-a-week operation with anelectricity cost of $0.0404 per kilowatthour.Testing:Testing started with the mica bandsalready in place on the injectionmolding machine. Ten were installedon the barrel and three more wereon the transition, not including thenozzle bands. The goal was to firstanalyze start-up time and temperaturerise and then analyze energyusage during a normal run. Sincethe mold- an automobile sunroofwasnew for the plant- figures werenot established on the quantity ofsunroofs produced in a normal run.The thermocouples and controllersthat were already installed on thebarrel for barrel temperature monitoringwere used in the testing procedures.A surface temperatureprobe measured the outside surfacetemperature of the mica and MIBands. A power analyzer was usedfor voltage and consumption measurements.The analyzer was connectedto the main power leadssupplied to the Toshiba injectionmolding machine. The power analyzercontinuously reads the inputvoltage and current and <strong>com</strong>putespower factor and actual power usedin a given time.The power connections consistedof voltage taps on all three-phasesplus a leakage indication on thecenter leg and a true ground determinationfrom the plant ground.Portable coil transformers were usedto determine current usage.The first day of testing includedrunning the part with an 80-secondcycle time running at a barrel temperatureof 280°C (540°F).$33,000$32,000$31,000$30,000$29,000$28,000$27,000Annual Machine Power Consumption$32,784.46Results:The test results showed 12.26percent yearly energy savings withthe use of Watlow’s MI Band heatersover mica bands. Using this rate tocalculate electricity usage (savingsbased on a 24-hour-a-day, sevenday-a-week,52-weeks-per-yearusage) the annual savings would be$4,024.68 at $0.0404 per kilowatthour. Considering the cost of a newset of heaters, payback would beachieved in less than seven and ahalf months.While the electrical savings are verysignificant, there are also very reallong-term savings from downtimedue to faulty heaters. DJ/Nypro alsorealized benefits from the simplifiedset up of the MI Band heaters thatresulted in reduced down time.Mica Band$28,759.78WatlowMI Band$26,000$3.7258 Mica cost/hr X 24 hrs/day X 7 days/wk X 52 wks/yr= $32,784.46 Mica Band Annual Electric Cost$3.2921 MI cost/hr X 24 hrs/day X 7 days/wk X 52 wks/yr= $28,759.78 MI Band Annual Electric CostWatlow’s MI Band heaters saved DJ/Nypro$4,024.68 per year in power consumption.62