PRODUCT OVERVIEW ① CARTRIDGE HEATER
■ Basic Structure Drawing
■ Notes on handling 1) Water adhesion If water (humidity) enters inside the heater, it may break insulation and cause shorts of the heater and breakage of the controller for the heater. If the heater shorts out, it may cause a break in the heater and heating and ignition of lead wires. 2) Oil adhesion If the heater is inserted into mold with oil or used under a situation where the heater gets oil on it, oil carbonizes and it may cause abnormal heating and shorts of the heater. Please be sure to remove oil completely before use. 3) Heating of the heater in air If you remove the heater from the mold and heat it in air, it may cause abnormal heating and shorts of the heater because the heater can dissipate less heat in air. Even if the heater is mounted to the mold, but the heat generator or the stainless sheath (bottom or tip) is exposed to the air, it may cause abnormal heating and shorts of the part. 4) Prohibition of the use with more than the rated voltage (V) If you use the heater with more than the rated voltage, it may cause abnormal heating, breakage and short–circuit of the heater. It may also cause shorts inside the controller for the heater. 5) Control method of the controller for the heater In order to gain stability in mold products and longer lifetime of the heater, use a PID heater controller. ■ How to select a heater ① Calculate necessary wattage (W) for a heater to raise mold temperature up to a preset temperature. It is calculated from the mass of the object to be heated, the specific heat, increase in temperature, and the time required to heat to the set temperature of the mold by the following formula. Weight of heated object (kg) × Specific heat of heated object (kcal/kg∙°C) × Temperature increase (°C) 860 × Heating time (h) × Efficiency ( η ) Though it is difficult to calculate accurately efficiency ( η ) because it varies on conditions of heat–retention, heat insulation, arrangement of the heater, etc., generally 0.2–0.5 is suitable. Material Specific gravity (g/cm 3 ) Specific heat (kcal/kg∙°C) Steel 7.85 0.113 Stainless Steel 7.82 0.110 Aluminum (A7075P series) 2.80 0.230 Brass 8.70 0.100 Example) Necessary wattage when controlling stainless mold of 130kg with heater and raising mold temperature up to 110°C in 30 minutes (Temperature = 21°C, efficiency η= 0.5) Necessary wattage for heater (kW) = 130 × 0.11 × (110–21) = 6(kW) = 6000 (W) 860 × 0.5 × 0.5 Necessary wattage for heater (kW) =
① Stainless sheath
② Magnesium oxide (Insulating powder)
⑤ Lead
④ Exotherm (Nichrome wire)
③ Core
⑥ Insulating glass
■ Heater selection chart
Shape
Shaft diameter/Length/ Wattage/Voltage
Function
Straight
With ange
Others
Output selection type MCH/MCHV D P.1056/1057
Output selection type MFCH D P.1058 With lead protection cover MCHJ D P.1060
Standard
You want to bend and/ or protect leads Applicable for sprue and nozzles
Fixed size
Band heater MBH D P.1074
Cartridge heater L dimension/Voltage/Wattage selection MSCH □ D P.1059 High wattage cartridge heater/Bottom reinforced type L dimension/Voltage/Wattage selection MSCHW □ D P. 1063 / MNCHW □ D P. 1064 With lead protection cover L dimension/Voltage/Wattage selection MJCH □ D P. 1061 Bottom reinforced type L dimension/Voltage/Wattage selection MNCH □ D P. 1062 Knurl cap type L dimension/Voltage/Wattage selection MRCH □ D P. 1065 Sensor attached type L dimension/Voltage/Wattage selection MTSJCH □ D P. 1070 Soaking type L dimension/Voltage/Wattage selection MKCH □ D P. 1066 Soaking type With lead protection cover L dimension/Voltage/Wattage selection MKJCH □ D P. 1067 Tip part heating type L dimension/Voltage/Wattage selection MTCH □ D P. 1068
Standard
You want to raise the temperature ef ciently Break-resistant lead wire bottom With a cap to hold for frequent removal Sensor attached type for limited space L-shaped for limited space You want to bend and/ or protect leads
Free to select
L type L dimension/Voltage/Wattage selection MLCH □ D P.1069
② Calculate number of heaters and wattage (W) for one heater Decide the number of the heaters depending on the size of object to heat, and get total wattage required to rise the temperature of it. Example) Use six heaters of approximately 1000 (W) (Total 6000W). ※ Heat loss is not taken into account. Please consider approximately 20–30% increase for the calculated value in wattage.
Standard
You want to bend and/ or protect leads
Selectable heat generator details
■ How to select a cartridge heater type • For fixed size
Heatable tip
Flexible Heater MSCHS D P. 1071
You want to bend the heater
① Select a heater diameter and its length.
② Select usable voltage.
③ Select necessary wattage.
Q How to mount cartridge heater ① Process for mounting hole • Specify the recommended hole diameter tolerance on the plate such that D dimension is H7 or within D+0.1. • For high watt cartridge heaters, set within D+0.03. If clearance between the mounting hole and the heater is bigger, the heater may have abnormal heating and it may cause a break and ignite. • We recommend applying reaming to the mounting hole. • We recommend using lubricating oil for cartridge heater in order to help more uniform radiation. (Anti–seizure agents are mentioned on P.1072 and 1073 ) ② Extended part of the heater Avoid popping out the heater from the plate as it may lead to abnormal heat generation. (The
MFCH12 － 180
MFCH12 － 180 － V200
MFCH12 － 180 － V200 － W700
• For variable size
② Extended part
Straight heater
① Select a ange shape.
② Set a heater diameter and its length.
③ Select voltage.
④ Select necessary wattage. ※
MSCHA12 － 300
MSCHA12 － 300 － V200
MSCHA12 － 300 － V200 － W1400
MSCHA
Insulating glass
※ For a variable–size heater, specify the wattage such that the watt density is 2 ≦ W/cm 2 ≦ 15 when setting wattage. The heaters whose watt density (W/cm 2 ) is low last long and have more stable control.
heater can stick out from the insulating glass and the flange.) ③ Distance between the heater and the temperature sensor
Heater with flange
10mm or longer is appropriate for the distance between the heater and the temperature sensor (thermocouple). If they are too close, it may cause malfunction of the temperature sensor. (Except for the sensor attached type) ④ Lead handling Note that lead wires may break if you repeatedly bend them.
Watts (W) Heat generator length × Heater diameter × 3.14
④ Lead
Watt density (W/cm 2 ) =
Temperature sensor
1049
1050
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