Custom Manufacturing of Heating Elements
Heaters are designed and fabricated to solve your heating application. We are able to incorporate many design variations, bonding methods and control options to make your heater attach to your part and function the most effectively
All holes, cutouts, and notches are located per your specifications and fit your exact design requirements.
Mechanical fasteners can be used for heating applications on cylindrical parts or where the installation is temporary. Spring fasteners allow for variations in circumference while providing close contact with the part to be heated.
Typical fasteners include: Eyelets, shoe hooks, grommets, springs, kevlar lace, buttons, D-rings, belts, hook and loop (Velcro™) fasteners.
Standard leads for heating elements are flexible silicone rubber insulated, UL Style 3135, and rated for 200°C/600 volt operation. Electrical wire lead types and exit locations are adaptable to application requirements.
Silicone rubber can be bonded to metal parts to create complete thermal sub-assemblies. Since a perfect fit between heater and your component is a vital factor in heater efficiency, we can factory bond or vulcanize the heater to the part in our factory, and thus assure optimum contact.
The maximum service temperature of this high temp silicone pressure sensitive adhesive (PSA) is 500°F (260°C). Bond strength is improved if a dwell time of 12 hours is observed before heater operation.
For lower temperature applications we utilize acrylic pressure sensitive adhesive (PSA) that is rated 250°F (121°C). Bond strength is improved if a dwell time of 12 hours is observed before operation.
We also have other adhesive options available, contact us for your application specific requirements.
Room temperature vulcanizing (RTV) silicone rubber adhesive can also be used when bonding heaters in the field. Heaters can be bonded to your parts at our factory, or we will supply recommendations for proper application.
Heaters can be fabricated with thermostats, thermal fuses, temperature sensors, thermocouples and resistance temperature detectors (RTD) as an integral part of the heater.
Snap action and creep action are two different types of thermostats. Both are based on a bimetal expansion-contraction principle and nearly all are pre-set to a specific temperature (non-adjustable). If the heater application requires very close temperature control an electronic controller with sensor is suggested over the mechanical thermostat.
Freeze protection, enclosure temperature and high limit protection are the applications best suited for the low cost mechanical thermostat.
The creep action units are constructed with a bimetal strip that curves with the temperature excursions to provide the mechanical action of make and break for the contacts. This provides a close differential between on/off, but can cause radio frequency interference in enclosures that have sensitive electronics. The temperature setting is factory preset and has the range of between 40°F and 300°F, +/- 5°F. Maximum amperage of these units is 8 amps at 120 volts. These small thermostats are commonly used as motor protectors or over temperature protectors in appliance applications.
The snap action units are round in construction (approx 5/8” dia.) due to the bimetal disk that provides the snap action. The disk is shaped similar to a contact lens and snaps back and forth at preset temperatures to make and break the contact points. The pros and cons of these types of units are:
Due to the energy required to snap the disk over center, the temperature differential between on and off is 20° to 30°F. When used as a high limit over 300°F this differential can be as large as 75°F. Maximum temperature for high limit is 500°F. The wide differential does not provide narrow band temperature control but also does not generate any radio frequency interference due to the positive make/break action. The most common use for these units is freeze protection and enclosure control with a setting of On at 40°F / Off at 60°F. These units must be covered with an overmold that is bonded to the heater.
Sensors can be located to monitor either heater surface or part temperature. Small sensors are held in place with a protective cover of silicone rubber/fiberglass vulcanized to the heater body. Larger sensors and thermostats have a protective cover (overmold) that is bonded to the heater body.
Thermal fuses open the circuit if the heater exceeds the selected fuse temperature. They are a one time over temperature protection device that can prevent heater runaway in the event that a control device has frozen in the on position. Testing is suggested to select the location and temperature setting of the fuse to protect your product most effectively.
Fuses are preset with a range of 150°F to 460°F. Electrical ratings are 120/250 VAC and 15 amp maximum. They must be covered or enclosed because the outer case of the fuse is electrically live.
Thermocouples & Resistance Temperature Devices (RTDs)
These devices are most commonly very small and can be attached to the heater with a patch of silicone rubber/fiberglass. Almost any type thermocouple can be used. Type ”J” is most commonly employed. RTDs are either 100 Ohm or 1000 Ohm two conductor type. Special sensors can be provided to your specifications and we can mount customer-supplied sensors.