History of Electric Induction Heating

This Chapter

Induction Heating
  1. Early work to Salesman
  2. Salesman to entrepreneur
  3. Vacuum furnaces
  4. Henry Rowan, Mars Rocket
  5. Cheston, Cragmet, IRS
  6. Visit Russia, Meet Vera
  7. Around the world, Meet the president
  8. Kramatorsk
  9. Consarc
  10. Consarc UK
  11. Carbon contract
  12. Russians in Scotland
  13. The Embargo is Coming
  14. Embargo and Aftermath
  15. BEPA
  16. After BEPA
  17. Fiber Materials Appeal
  18. Consarc Officials Deny Wrongdoing in Sales to Soviets
  19. Memos from Henry Rowan to Metcalf
  20. Rowland motor patent 1868
  21. Rowland reviews the bids for Niagara Falls power station
  22. Metcalf's father's poem, and Metcalf genealogy
  23. The Peace Treaty of Brest-Litovsk
  24. Problems of Russia's Policy With Respect to China and Japan
  25. History of Ajax Magnethermic
  26. The most important event for Inductotherm
  27. Fright Flight
  28. Black art of carbon production
  29. Polaris Missile
  30. Nuclear Airplane
  31. Nuclear Engine
  32. Molten metal eats through and explodes
  33. Cannon Muskegon Corporation
  34. Metcalf at General Motors Research from April 1955 to Oct 1955
  35. Metcalf pouring superalloy at GE from Oct 1955 to June 1956
  36. Metcalf at Waimet (later Howmet) from June 1956 to July 1957
  37. Black art of carbon production
  38. Project to test NASA hot hydrogen engine
  39. Special Metals Number 9
  40. Metcalf joins Inductotherm group
  41. Device to load materials into a furnace for melting
  42. Bank reneged on a commitment to finance a job in Russia
  43. Inductotherm private airport
  44. NERVA (Nuclear Engine for Rocket Vehicle Application) and all I know about carbon
  45. NERVA Engine Control Rods
  46. same as 383-Nuke.html
  47. Development of Polaris missle
  48. Ajax NASA
  49. Production of carbon fabrics and threads made from rayon
  50. George Houghton, Aerojet Inspector gives Metcalf Rocket history
  51. Rayon to carbon to graphite
  52. Metcalf buys the control division of the Pelton Water Wheel Company
  53. Rowan's account of firing Consarc President
  54. Kama Purchasing Commission, Ukraine
  55. Role of chromium in vacuum melters
  56. ASEA wins contract for isopress
  57. Induction heating to re-refile tank cannon
  58. Hoover-Ugine Company
  59. Letter to Henry Rowan at Inductotherm
  60. John Mortimer in Rancocas
  61. Consarc Board of Directors Meeting
  62. Consarc Board of Directors Meeting
  63. Hillbilly
  64. How to produce Calcarb
  65. Newsday, late 1987
  66. Embargo Regulations
  67. Seizure of Goods
  68. Minutes of Dept of Trade, London
  69. Minutes of ECGD Meeting
  70. Rowan Interview
  71. Bombshell looks like dud
  72. Letter to Hank Rowan
  73. Consarc Board Meeting
  74. Minutes of DTI Meeting, London
  75. Stansted Fluid Power
  76. Minutes of DTI Meeting, 3 Oct 85
  77. Letter to IHI Master Metals

Induction Heating

By James Farol Metcalf

Metcalf Pouring Superalloy at GE from Oct 1955 to June 1956

General Electric was looking for melters with experience with superalloy melting. My partner who had taught me how to melt left General Motors to work at General Electric. He helped me get the better paying position after only six months with General Motors. The new job was operation of a one ton vacuum induction-melting furnace. Their main contract was with the Allison Division of General Motors to produce metal for the turboprop engine for the Electra aircraft.

My job was to load the proper mix of pure metals into the furnace and push the button. I also had to load and unload the molds into which the liquid metal was poured for cooling. The equipment was just too fancy to do the simple job of melting and pouring in a controlled environment. The facility was not designed for the poor furnace operator that had to climb in and out of the chamber to accomplish the task. The precision valves and seals were always getting jammed with metal shot that was thrown from the metal surface during melting.

The job at GE taught me why and how to melt metal in a vacuum to produce the metals needed for the jet age. The new steels required for the jet age contain materials that burn to slag and leave inclusions in the metal if melted in normal furnace operation in air. When the melting operation was carried out in a vacuum the metal had a much better quality. The equipment was a simple induction furnace that was mounted in a large steel chamber. The air was removed from the chamber with vacuum pumps, so the metal could be melted and poured without the effect of air.

The GE furnace was designed to allow several melts to be made before vacuum was released in the melting chamber. This was accomplished using a mold chamber that was separated by a valve under the pouring point for the liquid metal. Molds were raised to the lip of the furnace by a long polished rod that passed through a sliding vacuum seal. There was a turntable with six positions in the mold chamber. High level management from GE headquarters attended the first production melt and I was the furnace operator. The alloy contained manganese that boiled and coated the sight glass during the melt so it was hard for the visitors to see the liquid metal. They departed just before the pouring operation. I knew there were four molds loaded on the six positions by the previous shift but I did not know where they were. I decided that number one must be full so I sent it up to pour. The only thing I could see was the red color of the melt and as bad luck would have it I dumped liquid metal on that beautiful polished shaft. My first design contribution to vacuum melting was a suggestion to use a four-inch gate valve so the sight glass could be changed if necessary.

My hands-on experience allowed me to understand what was needed from the operational point of view and to talk and think like an expert on this subject without understanding the metallurgy.

Hunting was very popular in Michigan and everybody wanted the four-day weekend off at Thanksgiving. I babysat the furnace twenty-four hours per day and earned enough to buy a good used car.