Barrel Heaters - Hasmak.com.tr

W A T L O WHot RunnerNozzle <strong>Heaters</strong>FIREROD CartridgeMaximum AllowableWatt DensityContinuedHeating Steam, Air and GasesAmbient Temperature—°FFIREROD Sheath Temperature—°F1600140012001000800600400200200015001000500Maximum Allowable WattDensity vs. Ambient Air10 20 30 40 50 60Watt Density—W/in 2FIRERODSheath Temperature WhenOperated in 210°C (70°F) Ambient AirNot Pre-oxidizedPre-oxidized10 20 30 40 50 60Watt Density—W/in 2Watt Density vs AmbientAir TemperatureThe Watt Density vs Ambient AirTemperature graph shows themaximum allowable watt densitywhen one FIREROD is operated inair or similar gas.For FIRERODs grouped in a singlerow, with no less than one diameterbetween elements, multiply valuefrom graph by 0.95. When a reflectoris placed behind the heaters,multiply the maximum allowablewatt density value from the graphby 0.85.Sheath Temperaturein Ambient AirThe Sheath Temperature in AmbientAir graph indicates the watt densityrequired to bring a pre-oxidizedFIREROD to a given sheathtemperature when operated in20°C (70°F) ambient air.At 6.8 W/cm 2 (44 W/in 2 ), the sheathtemperature would be 790°C(1450°F). At this temperature, oneyear life would be expected,provided that cycling is not toofrequent.Higher temperatures would result inreduced heater life.Injection MoldingHot Runner Nozzle <strong>Heaters</strong>Air Velocity Past Heater—FPM45004000350030002500200015001000500Maximum AllowableWatt Density in Moving AirEntering AirUp To 93°C (200°F)FIREROD–Parallel To Air FlowFIREROD–Perpendicular To Air FlowWatt Density in Moving AirThe Watt Density in Moving Airgraph gives the maximum allowablewatt density of a FIREROD inmoving air.The air movement is expressed infeet per minute (FPM). If the air flowis known in cubic feet per minute(CFM), divide the CFM by the netfree area around the heater (ft 2 ). Thenet free area is the total area of theenclosure minus the area occupiedby the heater.20 40 60 80 100 120Watt Density—W/in 214073