Introduction; Application; Operating Conditions; Principle Of Operation - Bessey PV Series User Manual

Safety features

The heater will switch off automatically if the ambient temperature exceeds 70ºC (158ºF).

When using the temperature mode, the heater will switch off automatically if the rate of
temperature rise is too low.

On models equipped with a swing arm, the arm can be fixed in the open position.
Caution:

Induction bearing heaters work due to a magnetic field. Please always keep at least a meter
(39 IN) from the unit during operation. Bear in mind that this can influence electronic
equipment, e.g. watches, magnetic charts etc.

2. Introduction

2.1 Application

Induction Heaters are designed to heat bearings, bushings, gear wheels, couplings or other
metallic work pieces which form a closed electrical loop. This will facilitate mounting where an
interference fit is required.
The heaters are designed to heat the work piece up to a maximum temperature of 240ºC (464ºF),
with the exception of the PV2412 model where the temperature is limited to a maximum of 150ºC
(302ºF) and special custom-designed heaters where the maximum temperature can be as high as
480ºC (896ºF).
Induction heaters PV/PVH/SVH can be used on continuous basis. There is however a limitation;
do not operate heater at a temperature of 240°C (464°F) or more for more than half an hour. By
heating with the time function this has to be checked with an external temperature meter.
Caution:

Bearings generally should only be heated up to a maximum temperature of 120ºC (248ºF).

Precision bearings should only be heated up to a maximum temperature of 70ºC (158ºF).
Heating to higher temperatures may affect the metallurgical structure and dimensional stability
resulting in premature bearing failure or loss of bearing performance.

Do not use induction heaters for bearings or work pieces, which are outside the minimum, or
maximum dimensions as specified in the sales data sheet

Do not switch off the heater with the main switch while heating cycle is running

2.2 Operating conditions

Designed to be used in an industrial environment with an ambient temperature of 0ºC to 50ºC
(32ºF to 122ºF), and an atmospheric humidity of between 5% to 90%. The induction heater is
meant for indoor use only.

2.3 Principle of operation

The heater works in the same way as a transformer. The primary coil is the
heater and the secondary coil is the work piece.
When the heater is switched on, a high voltage, low alternating current passes
through the numerous windings of the primary coil. This induces a low voltage,
high current in the work piece acting as the secondary coil. This high current
results in the heating up of the work piece.
The current is only flowing in the work piece, hence it is only this which starts to
heat up. The work piece is automatically demagnetised at the end of each heating cycle.
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