parallel furnace, also known as pit furnace, is an industrial heat treatment furnace with a unique structure. The furnace is vertically downward, shaped like a deep well, and the workpiece is vertically placed into the furnace from the furnace mouth for heating. This unique design makes the parallel furnace the first choice equipment for processing long shaft and cylindrical workpieces. It is widely used in machinery manufacturing, steel metallurgy, petrochemical and other industries.
Structural features of parallel furnace
The main structure of the parallel furnace consists of furnace shell, furnace lining, heating element, furnace cover and lifting mechanism. The furnace is cylindrical or square, with a depth ranging from 1 meter to several meters, customized according to the size of the workpiece and production needs. The furnace cover usually adopts an electric or manual lifting mechanism to facilitate the loading and unloading of workpieces. Some deep well furnaces are also equipped with a forced hot air circulation system to ensure uniform temperature distribution in the furnace.
Heating elements are usually arranged on the side walls and bottom of the furnace, in the form of resistance wires or resistance bands, and are evenly arranged around the furnace to radiate heat to the workpiece surface from all directions. For heat treatment processes that require atmosphere protection, the parallel furnace can be equipped with an atmosphere circulation system and a gas inlet to achieve controlled atmosphere heat treatment.
Main types of parallel furnaces
According to different process requirements, parallel furnaces can be divided into various types:
Low temperature well type tempering furnace: The working temperature is generally below 650°C and is mainly used for stress relief tempering and aging treatment of workpieces.
Medium temperature well type heating furnace: Working temperature is between 650℃ and 950℃, used for normalizing and annealing of carbon steel and alloy steel.
High temperature pit heating furnace: The working temperature can reach 1300℃, used for quenching and heating of high-speed steel and high-alloy steel.
Pit type carburizing furnace: Equipped with a carburizing atmosphere supply system for surface carburizing treatment of workpieces.
Process advantages of parallel furnace
The parallel furnace has the following significant advantages in heat treatment production:
1. Adaptable to long workpieces: The vertical charging method makes it particularly suitable for processing long-length shafts and pipe workpieces, avoiding the deflection problem of horizontal furnace loading.
2. Good temperature uniformity: Deep well structure combined with forced circulation fan makes the temperature distribution in the furnace more uniform.
3. Large furnace capacity: A single heat can process multiple long shafts, with high production efficiency.
4. atmosphere control: Can realize heat treatment processes in various protective atmospheres or carburizing atmospheres
5. Small footprint: Compared with bell-type furnaces and box-type furnaces, the parallel furnace occupies a smaller floor area.
Application areas of parallel furnaces
Parallel furnaces are widely used in the following industries and processes:
- Machinery manufacturing: Heat treatment of large parts such as long shafts, lead screws, gun barrels, turbine rotors, etc.
- Iron and steel metallurgy: Annealing and normalizing of steel rods, heat treatment of steel pipes
- oil drilling: Conditioning treatment of drill pipe and sucker rod
- Military products: Gun barrel and inner bore treatment of gun barrel
- Mold making: Annealing and quenching of long molds
Precautions for using parallel furnaces
In order to ensure the safe operation of the parallel furnace and stable product quality, attention should be paid during use: the workpiece should be placed vertically into the furnace to avoid contact with the heating element and cause a short circuit; the furnace loading capacity should comply with the furnace's rated power to avoid overload operation; the heating process should be carried out in accordance with the process regulations to prevent thermal shock from causing cracks in the furnace lining; regularly check the integrity of the furnace lining and repair damaged parts in a timely manner.
We provide multiple specifications of parallel furnace equipment, which can be customized according to your workpiece size and process requirements. Welcome to call us for detailed technical solutions and quotation information.
