Wed, 18 Jul 2018 02:02:56 +0000
Composition of vacuum sintering furnace
1. The furnace:
Using double-layer water cooling jacket structure, cooling water is passed into the interlayer, which can ensure that the temperature of the outer wall of the furnace body meets the national safety standard under high temperature heating. The material of the furnace body is carbon steel.
Oven door and furnace body through a hinge, USES the wrong tooth body lock, solved under the working condition of high vacuum and positive pressure alternating between the furnace body and oven door seal, and under the condition of positive pressure furnace body and the strength of the oven door. The opening, closing and locking operation of furnace door is simple, flexible, safe and reliable. 5 point temperature measuring flanges are reserved on the furnace body to facilitate users to detect temperature uniformity in the process of use.
2. Heating chamber:
Stainless steel frame is adopted, the outer cylinder body is 2mm stainless steel plate, and multiple reinforcing bars are adopted to ensure the long-term use of unchangeable type. The inner part is 20mm thick graphite felt tube, and the middle layer is 80mm soft carbon felt. The heating body is arranged in a graphite circle. The t-type 95 ceramic material and boron nitride material are used for insulation to increase the section area and reduce the pollution of volatile matter. The graphite tube is used to measure temperature, so the structure can avoid the influence of pollutant on the temperature control precision of infrared thermometer during sintering. The front of the hot chamber is equipped with an inflatable interface for degumming. Exhaust outlet and degumming water cooling pipe are arranged at the rear end of the heating chamber.
3. Air cooling system:
Furnace back with axial flow fan and cooling gas after copper, copper heat exchanger cooling by circulating air duct to the front of the heating chamber, the heating chamber before screen driven by the cylinder, the wind to the front of the workpieces after the throttle discharge circulating cooling. The motor is arranged on the water-cooled flange to ensure the long-term stable operation of the motor. The motor and water-cooled flange and impeller can be directly disassembled from the upper part to facilitate maintenance.
4. Vacuum system:
It is composed of rotary vane pump, roots pump, vacuum baffle valve, stainless steel corrugated pipe, electromagnetic relief valve (to prevent oil return) and vacuum tube circuit.
5. Pneumatic dewaxing system:
The inflating system consists of electromagnetic valve, fine tuning valve, pipeline, barometer, etc. When the inflating pressure reaches the set point of the upper pressure, it can stop the aeration automatically. When it is below the set point of the lower pressure, it can also supply air automatically. The defocusing gas valve automatically opens when the pressure setting is reached. The degumming gas goes through the pipeline through the degumming tank into the vacuum pump and out of the room.
6. Electrical control system:
The control cabinet is a standard electric control cabinet structure with integrated ventilation system, which can ensure that the normal use of components and instruments in the cabinet will not be affected by the high ambient temperature. There is a sound and light alarm above the cabinet. The electrical control system is concentrated in the control cabinet and adopts touch screen and PLC linkage control. The process setting and daily operation can be completed through the touch screen.
The control department is allocated with air switches, buttons, contactors, relays, indicator lights and other components to realize the logical control of external equipment through signals of various sensors. The overall operation of the equipment can real-time display on the LCD screen, working condition of all the action is equipped with safety interlock protection, overtemperature without electricity or maintain, water power (delay stop heating, vacuum pump, etc.), air pressure protection, etc.
Operating system interface to realize various operating instructions and process condition, design a system to monitor the picture at the same time, fault handling pictures and help interface, the system can at any time to view, record in running a variety of data. The red flash indicator on the panel is used to display various alarm functions. The operator can determine the alarm position and handle it immediately according to the prompt.
The temperature control part consists of temperature control meter, armored k-type single-core thermocouple, infrared thermometer and thyristor voltage regulator. Low temperature heating section within 900 ℃ using K temperature control, up to 900 ℃ after into infrared measuring temperature, thermocouple through heating cylinder is transferred to outdoor at the same time. Ensure the long and effective service life of thermocouple.
The heating power is supplied by thyristor power regulator. Feature 2: it has the advantages of soft start and soft shutdown, which can protect the power supply and reduce the impact on the load. Feature 3: wide range of pressure regulation, with constant current function, overcurrent and overheat protection function.
7. Water cooling system:
The cooling parts include furnace body, furnace door, vacuum unit and water-cooled copper electrode. The pipe and valve are made of 304 materials and nameplate is installed. The inlet pipe is equipped with a contact pressure gauge, and the return pipe is equipped with a flow scope. When the water pressure is below the set value of 0.15mpa, the acoustooptic alarm is started and the heating state is stopped.
The cooling water system is provided with emergency bypass water supply interface and tap water connection, with manual ball valve. When the equipment is not normally power off, open the emergency tap water valve to ensure the natural cooling of the equipment.
The cooling water is supplied by circulating water in the closed cooling tower. The cooling tower can supply water automatically, save water and be safe and reliable. (not included in the quotation)
8. Pneumatic system:
Including pneumatic triplex, electromagnetic directional valve, cylinder and nylon hose, can provide clean compressed air.