|Fully automated tempering plant with two chamber furnaces, quench bath, conveyor system, and parking spots for four charge baskets||Annealing furnace with manipulator|
To temper steel, after annealing the furnace is opened at working temperatures of more than 1000 °C. The lift door opens and the manipulator places the charge into the quenching medium. After quenching the charge is placed into the forced convection chamber furnace for tempering. Good temperature uniformity is important.
Oil or water is used as a quenching medium. Depending on the steel grade and the required cooling rate, the charge can also be force-cooled or quenched in an air quenching chamber.
Alternative plant designs are tailored to process requirements. For lighter charge weights a manual tempering plant can be used, consisting of an annealing furnace, quench tank and manual manipulator. Semi-automatic or fully automatic plants are used for heavy loads and high throughput rates. The charge is placed into the hot furnace and subsequently into the quench tank by a manipulator.
The customer specifies the needed quenching delay time for the individual process counting from opening the furnace door until the charge is completely immersed in the quenching medium. Fast delay times are only possible with a powered manipulator. If the quenching delay time is not so critical, for example for heavy and thick-walled parts, bogie hearth furnaces can also be used. The bogie is driven out of the furnace electrically and the components can be transferred and quenched by a crane.
Top hat furnaces are suitable for long components or for processes with no need for short quenching delay times. The top hat is opened while the furnace is hot and the charge is then transferred and quenched by the customer’s crane with a C-hook.
Annealing Furnace Design Alternatives
- Chamber furnace with radiation heating and a lift door for charging with a manipulator
- Bogie hearth furnace with powered bogie for charging with a crane for low quenching delay time requirements
- Top hat furnace for long components, such as rod material for charging with a crane and C-hook
Quenching Design Alternatives
- Quench tanks with water, oil or polymer as a quenching medium
- Cooling station with powerful fan cooling for air quenching.
Charge Transfer Alternatives
- Manual manipulator for manual tempering plants
- Electric manipulator for manual tempering plants
- Rail-mounted 2-axle manipulator, semi-automatic for charging, unloading and quenching the charge in a liquid medium
- Rail-mounted 2-axle manipulator, semi-automatic or fully automatic for charging, unloading, quenching, subseguent tempering in forced convection furnace or transferring to a holding position