Epoxy Glass Fibre Tube
Epoxy Glass Fibre Tube
Epoxy Glass Fibre Tube Epoxy Glass Fibre Tube Epoxy Glass Fibre Tube

The impeder is usually a ferrite rod inside a fiberglass or quartz shield. The purpose of the shield is to protect the ferrite from damage and to channel the cooling water around the ferrite. However, it is the ferrite that controls themagnetic field generated by the work coil. Hence the dimensions of the ferrite – not the dimensions of the shield –affect the results of the process.

Impeders should be chosen and positioned according to the following guidelines:

The ferrite’s diameter should be as large as is practical. In general, its diameter should be 75% of the tube ID.
In large pipe or tube fabrication, where multiple ferrite rods are used or in cases where internal scarfing deviceslimit placement of the ferrite within the tube, the ferrite should be placed as close to the vee as possible.
The length of the impeder should be chosen so that the “head roll” end of the ferrite (not the end of the housing)extends approximately 0.125-0.25beyond the apex of the vee (past the head rolls), and the other end of theferrite extends approximately two tube diameters up-stream from the work coil.
Identify the inside diameter of the pipe or tube to be produced