It Pays To Switch To Electric

John M Henderson & Co Ltd, established since 1866 has built up a world wide reputation for the quality of its mechanical handling products. Post weld heat treatment is central to their manufacturing process and had been traditionally carried out in brick lined gas fired furnaces.

These were very inefficient, requiring frequent downtime for maintenance and creating an unpleasant working environment.

Subcontracting of large structures was necessary because of limited capacity of the furnace. When it was decided to relocate its manufacturing facility from Aberdeen to Arbroath taking this opportunity to review its heat treatment requirements.

Gas and Electric furnaces were carefully considered. The company finally decided to install a new microprocessor controlled Electric Bogie Hearth Furnace rated at 750 KW with sufficient capacity to accommodate all their requirement. Maximum working temperature is 850°C. The advantages the electric furnace offered were its ability to achieve a wide range of treatments under fully automatic control. Programmable heating and cooling cycles offer ramp, soak and cooling periods. Permanent furnace control charts records for customer retention show that the correct treatment cycle has been applied.

Better metallurgical control was also achieved because electric heat treatment gives the correct combination of mechanical properties with minimum scaling and a significantly reduced risk of rejects.