Examples of this are galvanised tubes (to prevent ‘white rust’ formation) and also stainless steel tubes (to avoid coolant in the welding zone).
Replacement cut-to-length casings and ferrite cores are available from stock. We now also offer RFI impedors with our S300WG casings. This unique white fluoro polymer offers excellent non-stick properties and increases casing temperature endurance by almost 100ºC.RFI impeders have significant advantages over other return flow designs such as:
- Rugged CNC machined brass internal assemblies
- Centre tube pinned to end plug avoiding any possible detachment during production
- High temperature glass casing
- High temperature O rings
- NPT tapered thread connections to ensure full leak proof connection
- No drilled holes or fasteners in casing body
We offer a variety of impeder couplings/supports for return flow impeders
Return flow impeder cooling
Return-flow impeders may offer more resistance to coolant flow than through-flow types, a higher coolant pressure is therefore recommended. A minimum pressure of 5.5Bar(80Psi)’ensures adequate cooling under most operating conditions. Coolant flow requirements vary widely due to inlet temperature, weld power, frequency and weld area geometry. Clean filtered coolant is recommended when using return-flow impeders. Since coolant flow can be reduced at lower inlet temperatures, it is beneficial to keep the inlet temperature as low as possible. This may require the use of a heat exchanger or refrigerative cooler when using return-flow impeders. Coolant temperature entering the impeder should be below 20C/70F to ensure optimal performance and lifetime.