Subhot Industrial

Coil & Hot Runner Heater/ Mica Band Heater / Ceramic Band Heater

Applications

Hot runner heaters are essential components of hot runner systems, which are used to convey molten plastic from the injection molding machine to the mold cavities. Hot runner heaters are responsible for heating up the plastic inside the mold and maintaining a constant temperature throughout the process.
Hot runner systems have many advantages over cold runner systems, such as:
- Reduced material waste and cost
- Improved product quality and consistency
- Faster cycle time and productivity
- Easier color change and material change
- Lower environmental impact

There are different types of hot runner heaters available in the market, depending on their shape, size, material and design. Some of the common types are:

- Coil heaters :   These are flexible heaters that can be bent into various shapes and sizes to fit into complex mold geometries. They have a high power density (up to 60 W/cm2) and fast heat transfer rate (up to 50°C/s). They are made of nickel-chromium alloy wire wrapped around a ceramic or metal core. They can withstand temperatures up to 900°C.

- Cartridge heaters :   These are cylindrical heaters that can be inserted into holes or grooves in the mold. They have a low power density (up to 15 W/cm2) and slow heat transfer rate (up to 10°C/s). They are made of nickel-chromium alloy wire embedded in a ceramic or metal tube filled with magnesium oxide powder. They can withstand temperatures up to 800°C.

- Tubular heaters :   These are rigid heaters that can be formed into straight or curved sections to fit into simple mold geometries. They have a medium power density (up to 30 W/cm2) and heat transfer rate (up to 20°C/s). They are made of nickel-chromium alloy wire coiled inside a metal tube with fins or ribs for better heat dissipation. They can withstand temperatures up to 700°C.

MICA BAND HEATER

Mica band heaters offer efficient and economical solutions for heating cylindrical surfaces that require indirect external heating. They are ideal solution for high watt density and high temperature applications. It uses nickel chromium resistance strip as heating element which is precisely wounded on a dielectric material for even heat distribution. The heating element is insulated within a mica core enclosed in a metal sheath which provides exceptional insulation, dielectric strength and heat transfer capability for faster heat up and longer heater life. Heaters can incorporate various sized holes and cut-outs and are customizable for various dimensions, wattages, voltages and materials to suit different application requirements. Mica band heaters can also accommodate built in thermocouple which helps in controlling temperature more accurately. Thermocouples can be of type “J” or type “K”, grounded or ungrounded.

Technical Specifications

Max. Sheath Temperature	450°C
Voltage	120 V & 240V, Single Phase, 2 Phase, 3 Phase
Watt Density	Up to 45 W/in2
Minimum Diameter	2”
Minimum width	1”
Regular Gap	3/8”
Terminal Enclosure	Regular or moisture-resistant terminal box
Control	Thermostat or Thermocouple

Applications

• • Injection, Extrusion and Mlding Processes.
• • Plastic Processing Industry.
• • Chemical Industries.
• • Food Processing Industries.
• • Oil Lubricating Unit.
• • External Tank And Vessel Heating.
• • Blown Film Dies.

Features

• • Injection, Extrusion and Molding Processes.
• • Plastic Processing Industry.
• • Chemical Industries.
• • Food Processing Industries.
• • Oil Lubricating Unit.
• • External Tank And Vessel Heating.
• • Blown Film Dies.

Ceramic Band Heater

Ceramic Band Heaters are manufactured by using special ceramic insulation material ' Steatite ' and fabricated with stainless steel sheet. The heating coils is made of high quality Nichrome wires.The spot welded clamp bars, Allen screw clamping provides a uniform clamping.

Ceramic Band Heaters are used for heating of moulds,dies,nozzles and barrels on all types of plastic processing machinery.Heaters having high watt densities provide high operating temperature, resulting into high productivity. Its Maximum sheet temperature up to 800 degree Celsius and

Its Maximum Watt density up to 50 Watts per Square Inches for the blower air cooling, the perforated ceramic heaters with cooling fins or without cooling fins can be manufactured as per customers specification.

Technical Specifications

Sheath Material	Aluminium coated or Stainless Steel
Insulation Material	Ceramic Fiber Blanket
Watt Density	Up to 45 W/in2
Watt Ratings	500 – 5000 W
Voltage	120 V & 240 V, single phase, 2 phase and 3 phase
Width	25mm – 250mm
Diameter	40mm minimum, expandable up to 1200mm in 3 parts.
Operating temperature	650°C

Applications

• • Plastic injection molding machine.
• • Plastic extrusion machine.
• • Waste incineration.
• • Pipeline heating.
• • Semiconductor industry.

Features

• Lower Operating Cost – Less heat escapes to the air and less wattage is required to maintain barrel temperature, due to superior insulation.
• Heat transfer – Conduction and radiation are used as the means to transfer heat, thus they are less prone to thermal expansion problems and a near perfect fit is not required as with other heaters.
• Longer Heater Life – All materials used are rated to operate at very high temperatures.
• Higher Operating Temperatures.
• Flexible – Easy to install and remove.
• Uniform heat distribution.