650 degree aluminum alloy rapid quenching furnace T6 heat treatment process
1.Overall view
The aluminum alloy quenching heat treatment resistance furnace is a periodic operation resistance furnace, which is mainly used for solid solution treatment such as rapid quenching and tempering of aluminum alloy castings.
2.Advantages
The workpieces of the furnace adopt hanging operation, with good thermal cycle state and uniform temperature.
After the completion of heating and holding stage, the workpiece can quickly fall from the furnace to the quenching medium in the pool within 12 seconds, and the quenching treatment quality is high.
The temperature control system adopts PID zero crossing trigger thyristor and Shanghai Guolong high precision with intelligent temperature control meter, the fast quenching heat treatment furnace has good stability and over-temperature alarm to ensure that the workpiece temperature does go overhigh.
Each mechanical transmission part of the electric resistance furnace adopts interlocking control and operation.
3.Main Technical Parameters
(1) Rated power: 100kW ± 10%
(2) Rated voltage: 380V, 3P, 50Hz
(3) Rated temperature: 650 ℃
(4) Temperature control mode: PID control
(5) Number of heating zones: 1 zone connection method: Y;
(6) Uniformity of furnace temperature: ≤± 5 ℃
(7) Temperature control accuracy: ± 2 ℃
(8) Effective workspace size: 1300×1300×1300mm
(9) Quenching transfer time: ≤ 12s (furnace door open to workpiece water)
(10) Heating time of empty furnace: ≤ 2H
(11) Empty furnace loss power: ≤ 12KW
(12) Fan power: 3kw
(13) Charge lifting motor: two speed motor
(14) Furnace side outer wall temperature: ≤ 35 ℃
(15) Basket: 1 set
4.Structure introduction
The electric heat treatment furnace structure is composed of heating furnace, lifting mechanism, quenching mechanism, control system, etc.
4.1 Heating furnace
The shell frame of the furnace body is welded by profile steel, and the inner wall is welded by 1Cr18Ni9Ti heat-resistant stainless steel plate. At the same time, in order to avoid the deformation of the stainless steel plate in the inner chamberr at high temperature, the stainless steel plate also has expansion slots. The lining is of all fiber structure, and a layer of rubber asbestos plate is attached to the inner surface of the furnace shell, which plays the role of heat insulation and protect the furnace shell surface from corrosion.
The heating element for rapid quenching heat treatment furnace is pressed into a strip with 0cr25a15 alloy, sleeved on the insulating porcelain tube and fixed on the inner chamber of the furnace body through stainless round steel. This structural resistance strip is hung around the furnace, which is conducive to heat dissipation and circulation.The heating element adopts Y-connection method.The surface load shall be controlled below 1.6w/cm2 to prolong the service life of the equipment.
The hot air circulation device is composed of fan device and air guide plate. The fan device is placed on the top of the furnace body, and the fan is made of 1Cr18Ni9Ti heat-resistant steel into centrifugal fan blades.The air guide plate is made of 1Cr18Ni9Ti heat-resistant steel, and is fixed on the inner wall of the furnace through several supporting rods. The resistance strip is wrapped inside, and the heat emitted by the resistance strip is thermally circulated through the hot air circulation system to make the temperature in the furnace uniform.The ventilation device is made according to the T6 heat treatment furnace volume and forced hot air circulation to meet the requirements of uniform furnace temperature.
The base frame is used for loading furnace parts and is welded with section steel.
The shell of the furnace door is welded with steel, and the lining is of all fiber structure.
The sealing between the furnace door and the furnace body adopts the worm gear reducer to work, and the automatic inertia sealing is carried out after it is in place.
The electric resistance furnace is equipped with a charging trolley.
4.2 lifting mechanism
The lifting mechanism is composed of winch, loading frame, lifting chain, rolling wheel, etc.
The winch is installed on one side of the base frame. It adopts a low-speed ratio reducer and is equipped with a self-locking device, which can ensure that the charging frame stays at any position and decelerates, so as to prevent the rapid impact of the charging frame on the quenching tank when it drops.
The lifting motor adopts two-speed motor, which is slow when lifting and fast when descending.
The loading frame is made of section steel or round steel according to the user's requirements, and one set is provided.
4.3 control system
The temperature control system adopts PID zero crossing trigger thyristor and Shanghai Guolong intelligent meter to control the temperature. It has overtemperature alarm function to ensure that the workpiece temperature doesn’t go overhigh.
The mechanical transmission parts of the electric heat treat furnace adopt interlocking control, that is, after the furnace door is slightly opened, the power supply of the ventilator device and heating parts will be cut off automatically, and the power supply of the lifting device will be restored automatically. After the charging frame reaches the designated position of the furnace, the power supply of the lifting device will be cut off automatically when the furnace door is closed. After the furnace door is closed in place, the power supply of fan device and heating element can be connected to prevent accidents due to misoperation.
