Pit furnace are those furnace that are applied for heating various metals or alloys of metals. They are available in various sizes and are either gas fired or fuel fired. They can operate at various temperatures and are designed in such a way that the heat loss is minimum.

Safe operation, is an important aspect of this furnace because the fan and heating elements are separate from the load chamber. Due to this damage from accidental contact is eliminated. Metal lining is used in the entire work chamber which gives the furnace maximum durability.

Silent Features:
Following are the features of pit furnace:

• They can withstand continuous operation.
  
  
• Some of the pit furnace have plug in type of door/retort cover.
  
  
• Temperature is distributed uniformly.
  
  
• For longer element life heating elements operate on low surface load.
  
  
• The furnace is well insulated by using high quality bricks/ceramic fiber for energy conservation.
  
  
• Latest pit furnace uses automatic temperature control by digital controller with safety back-up non-indicating controller.
  
  
• Furnace operation is safe because of the use of safety interlocks and protection devices.
  
  
• Using fan motor with shaft and blades of heat resistant material with water cooled bearings air circulation is effected.
  
  
• Pit type furnace has very good hermetic sealing.

Advantages

• The pit furnace are highly productive.
• Temperature is distributed uniformly.
• The operation is very simple.
• The maintenance is easy and cost effective

Types
There are different types of pit furnace that are used:

• Element Pit Furnace
• Electric Pit Furnace
• Gas-Fired Pit Furnace
• Electric Retort Pit Furnace
• Gas-Fired Retort Pit Furnace
• Nitriding Pit Furnace
• Tempering Pit Furnace

Applications

• Gas Carburizing
• Carbo Nitriding
• Nitriding
• Heat Treatment
• Annealing
• Bright Hardening
• Bright Annealing
• Bright Normalising