Bolt Heaters are used to preheat large, hollow holding bolts or studs where a high concentration of heat is critical for bolt expansion in a short period of time. As an insertion type unit, the bolt heater is widely used in the manufacture and servicing of heavy duty steam or other pressure equipment. It is also used to heat die blocks and large platens and to expand adjusting bolts on mechanical or hydraulic presses.
Bolt Heaters are used as an aid to tighten large bolts in heavy machinery and equipment. Heaters are sized for easy insertion into a drilled hole in the bolt. The rapid heating of the bolt expands it allowing further tightening of the nut. The heater is then de-energized and removed. As the bolt cools its contraction back to original size provides a tight fit. Our bolt heaters are constructed with an efficient and high quality heating element.
Features:
- Swaged tubular heater construction
- 4″ octagon electrical enclosure with knock outs for easy wiring
- Insulated handle
- Special watt densities, wattages, and lengths, and diameters
- Flexible designs available
- Fast response time
- Power leads and plug assemblies
- High Temperature Lead Wires for temperatures up to 550° C.
- High Impact Ceramic Cap retards contamination and is suitable for high vibration applications. Deep holes in cap prevent fraying of leads when bent.
- Nickel-Chromium Resistance Wire for maximum heater life, evenly wound for even heat distribution.
- High Purity Magnesium Oxide fill selected for maximum dielectric strength and thermal conductivity, highly compacted for maximum heat transfer.
- 304 Stainless Steel Sheath for oxidation resistance in a wide variety of environments. 316 Stainless Steel and Incoloy® are also available. Please consult the Sheath Suitability Chart to determine which material is best for your application.
- TIG Welded End Disc to prevent contamination and moisture absorption.
Standard Specifications
| Nominal Diameter |
Minimum Diameter |
Maximum Diameter |
Std. Lead Wire Gage |
Max Amps w/ Std. Gage |
Max Lead Wire Gage |
Max Amps |
Max Volts |
|---|---|---|---|---|---|---|---|
| 1/8″ | .119 | .124 | 24 | 3.6 | 24 | 3.6 | 240 |
| 1/4″ | .244 | .249 | 24 | 6 | 22 | 9 | 300 |
| 6.5 mm | .250 | .255 | 24 | 6 | 22 | 9 | 300 |
| 5/16″ | .306 | .311 | 24 | 6 | 22 | 9 | 300 |
| 8 mm | .309 | .314 | 24 | 6 | 22 | 9 | 300 |
| 3/8″ | .369 | .374 | 22 | 9 | 18 | 15 | 480 |
| 10 mm | .388 | .393 | 22 | 9 | 18 | 15 | 480 |
| 12 mm | .466 | .471 | 22 | 9 | 18 | 15 | 480 |
| 12.5 mm | .486 | .491 | 22 | 9 | 18 | 15 | 480 |
| 1/2″ | .494 | .499 | 22 | 9 | 18 | 15 | 480 |
| 13 mm | .506 | .511 | 22 | 9 | 18 | 15 | 480 |
| 17/32″ | .525 | .530 | 22 | 9 | 18 | 15 | 480 |
| 14 mm | .545 | .550 | 18 | 15 | 14 | 26 | 480 |
| 5/8″ | .619 | .624 | 18 | 15 | 14 | 26 | 480 |
| 16 mm | .624 | .629 | 18 | 15 | 14 | 26 | 480 |
| 17 mm | .663 | .668 | 18 | 15 | 14 | 26 | 480 |
| 11/16″ | .682 | .687 | 18 | 15 | 14 | 26 | 480 |
| 19 mm | .742 | .747 | 18 | 15 | 14 | 26 | 480 |
| 3/4″ | .744 | .749 | 18 | 15 | 14 | 26 | 480 |
| 25 mm | .978 | .983 | 18 | 15 | 14 | 26 | 480 |
| 1″ | .994 | .999 | 18 | 15 | 14 | 26 | 480 |
- Length tolerance is +/- 3% or +/- 3/32, whichever is greater.
- Camber tolerance is .025″ per foot of length. Slight camber is normally not a problem since the heater will flex enough to enter a clean hole.
- Wattage tolerance is +5%, -10%