Lower Convection Furnace

The following is an SOP on using the lower convection furnace in the deformation lab. This furnace is often used for pre-heating extrusion tooling and billets.

Contacts

• Russ Stein (restein@mtu.edu)
• Dale Dewald (dkdewald@mtu.edu)
• Tom Wood (tdwood@mtu.edu)

Safety

• PPE:
  • Required:
    • Safety glasses
    • Steel-toed boots
    • Green jacket
    • Gloves rated to the proper temperature
  • Recommended based on temperature:
    • Full-face shield (for medium-to-high temperatures)
    • Silver jacket and spats (for high temperatures)
• PPE should be your last defense. All hot metal should be grasped with tongues, not gloves. Make sure the area is clear prior to opening the furnace or moving hot metal.
• When unloading hot metal, turn the furnace off before opening the door. This will reduce the heat in the air pumped through the furnace.
• The furnace measures temperatures in Fahrenheit. Be careful not to melt anything. Pure aluminum melts at 1,221°F, but alloys can melt lower.
• The samples being heated should not be in contact with the furnace wall, ceiling, or floor. They can be supported on ceramic blocks or aluminum profiles with an aluminum plate on top of them.
• Be advised that the furnaces temperature is often different than the metal temperature. A thermocouple touching the metal is the best way to read metal temperature.
• A quench pool is by the rollers at the end of the extrusion press. Be careful of steam when quenching hot metal.

Procedure

Figure 1. Closed furnace and control panel.

Figure 2. Open furnace with aluminum billets on top of an aluminum base plate and old profiles.

1. Use the arrows on the lower temperature panel to set the furnace to the proper temperature. Press the lower-left start button and close the door.
2. When ready to unload samples, turn off the furnace with the lower-right red button. Make sure the area is clear before opening the furnace.