BS EN IEC 63078:2020 pdf free download – Installations for electroheating and electromagnetic processing – Test methods for induction through-heating installations
The tests of an induction through-heating installation are divided into cold state tests and hot state tests. Unless otherwise specified, the hot state tests shall be undertaken after the cold state tests are qualified. The cold state tests shall be undertaken after manufacture or repair as well as during installation and regulation in the cold state. Installation and test preparation shall be carried out according to the manufacturer’s instructions. Before the test, the electrical connections, switches, control system and some dimensions, etc. of the installation shall be inspected.
The hot state tests shall be undertaken with a new lining of specified dimensions and materials as agreed between the manufacturer and the user. The requirements for test billets shall be in accordance with 6.7.1 01 . The technological process for heating and holding shall be agreed between the manufacturer and the user. The technological process also includes the loading, temperature measurement and unloading of billet. Where a test is to be performed in the hot state (see 3.1 23), the induction through-heating equipment shall have been in operation for at least 8 h (depending on the dimensions of billet or agreed between the manufacturer and the user) prior to the test. In the case where it starts with a new lining, it shall have been in operation for at least 24 h prior to the test.
The electrical data at the input of the supply line to be established by the tests of items b), c) and e) of 8.3 are related to the rated voltage U n and the rated frequency f n . Admissible deviations from the rated voltage and frequency shall be agreed between the manufacturer and the user. If during the test these deviations are exceeded, this shall be taken into account in the evaluation. In the case where a mains transformer is used solely for the induction through-heating equipment, the electrical values at the input of the supply line may be determined from the corresponding values on the secondary side of the transformer taking into account its characteristic.
Attention should be drawn to the different parameters to be considered as regards the rated values of an induction through-heating equipment and to the tests intended for their verification; irrespective of the size of the equipment, its performance depends on:
– the heating type of the equipment;
– the design of the equipment and its heating inductor themselves;
– the material, shape and dimensions of the billet;
– the type and automation degree of the handling mechanisms of the billet;
– the type and frequency of the power supply unit used to feed the equipment;
– the type of control and regulating system of the power supply unit for the equipment;
– the ability of the power supply unit of the equipment to react to rapid variations of reactive power.