Introduction; Intended Use; Principle Of Operation - SKF TIH 200m Mode D'emploi

1. Introduction

The SKF TIH 220m induction heater is designed to heat bearings, which are mounted with
an interference fit onto a shaft. The heat causes the bearing to expand, which eliminates
the need to use force during installation. A 90 °C (162 °F) temperature difference
between the bearing and shaft is generally sufficient to enable installation. At an ambient
temperature of 20 °C (68 °F), the bearing must therefore be heated to 110 °C (230 °F).

1.1 Intended use

The TIH 220m has been designed to heat rolling bearings. However, other metal
workpieces that form a closed circuit can also be heated. Examples of acceptable
workpieces include bushings, shrink rings, pulleys, and gears. All bearings that fit over the
induction coil and between the vertical supports with the top yoke in place can be heated
using the TIH 220m. In addition, smaller bearings can be placed over any of the two
standard yokes. See the illustrations at the beginning of this manual for examples.

1.2 Principle of operation

The principle of operation of the TIH 220m can be compared to a transformer.
The high voltage, low electrical current flowing through a large number of windings in the
TIH 220m's induction coil induces low voltage, high current electricity in the workpiece.
Because the workpiece has the electrical characteristics of a coil with a single, short-
circuited winding, the high current generates heat within the workpiece. Because the heat
is generated within the workpiece, all of the heater components remain cool.
6 SKF TIH 220m