Heat treatment furnace
Heat treatment furnace cold adjustment scheme
1. heat treatment furnace
Two new trolley type heat treatment furnaces are mainly used for heat treatment of forged products of alloy die steel, hot working die steel, roll steel and high quality carbon alloy steel. Two new trolley type heat treatment furnaces are mainly composed of furnace body steel frame, lining, trolley and towing mechanism, furnace door and lifting mechanism, sealing system, combustion system, pipeline and smoke exhaust system, automatic control system and other parts.
2. Heat treatment furnace purpose of cold commissioning
Through debugging, the technical properties of the heat treatment furnace meet the design requirements.
2.1 operational characteristics: verify whether the furnace equipment meets the design requirements when adjusting the mode.
Two point two
Free running function of furnace door and sealing of furnace door.
2.3, the free running function of trolley, the tightness of trolley and the stability of running position of trolley.
3. Heat treatment furnace steps of cold commissioning
Preparation: check the equipment according to the drawings and equipment list, prepare the mode.
3.1. piping system:
1) Blow-clean: After the pipeline is manufactured, the pipeline must be purged to prevent foreign bodies such as welding slag from entering the valve and breaking the important valve.
The natural gas pipeline, nitrogen pipeline and air pipeline are nitrogen washing medium.
B) matters needing attention in piping cleaning.
The pipe fittings that are not allowed to be washed should be temporarily dismantled and replaced by short pipes and after washing.
Before blowing, check whether the pipe support is firm and reliable.
The order of blowing and washing is in the order of main pipe and branch pipe. The dirt blown out is not allowed to enter the equipment or qualified pipe.
Each pipe should have an exhaust port.
The blowing pressure should not be less than 1.25 times the working pressure.
2) test pressure:
According to the specification, the natural gas pipeline and nitrogen pipeline must be compressed after completion. The test pressure is 1.25 times of the maximum working pressure of the pipeline, and the medium is nitrogen. During pressure test, the test pressure should be gradually increased slowly. When the pressure rises to 50% of the test pressure, if no abnormality or leakage is found, continue to press 10% of the test pressure.
Step-up, three-stage pressure test, each stage voltage for 3 minutes, until the experimental pressure, voltage for 5 minutes, and then pressure down to the design pressure, pressure 24 hours. Record the temperature and pressure at the beginning and the end of the test, and calculate the leakage rate, outdoor no more than 4%, indoor no more than 2% is qualified.
In order to ensure the safety of production, the natural gas pipeline must be purged when the first ignition after completion or the first ignition after long-term stoppage of the furnace. (purge nitrogen pressure should not exceed the inlet pressure of the natural gas before the pressure relief valve).
3.2 piping system commissioning:
1) combustion supporting air system:
Check whether all valves on the pipeline are working normally and whether the measuring instruments are normal.
Check whether all the executing agencies on the pipeline are working properly and whether manual operation is flexible.
Testing wind pressure of fan at maximum air volume;
Detect the linkage function of air solenoid valve and fan in front of furnace.
Check the adjustment function of the air double position disc valve in front of the furnace.
2) nitrogen system
Check whether all valves on the pipeline are working normally. Are all measuring instruments normal?
Check the pressure before and after the pressure reducing valve is correct, the electrical contact pressure gauge is normal, the pressure before the pressure reducing valve is 0.4-0.6 MPa, the pressure after the pressure reducing valve is 20-40 KPa.
3) natural gas system
Check whether all valves on the pipeline are working properly and whether the measuring instruments are normal.
Check the pressure before and after the valve is correct, the pressure gauge is normal, the pressure before the valve is 20-40 kPa, the pressure after the valve is 7-9 kpa.
Test whether the quick shut-off valve can work in the corresponding linkage condition and whether it can be cut off quickly.
Testing whether Tianxin flowmeter is refueling according to regulations.
Detect the linkage function of natural gas solenoid valve and fan and related valves before furnace.
Check the regulation of the valve before the natural gas.
3.3 mode of mechanical equipment
Furnace door lifting operation adjustment.
Sealing adjustment of furnace door.
Adjustment of furnace door proximity switch.
The adjustment and operation of the trolley.
The tightness of the trolley is adjusted.
The adjustment of the travel switch of the trolley.
The interlocking of furnace door and trolley movement is set.
3.4 commissioning of electrical equipment.
Instrument and electrical equipment debugging, without input / output conditions, all instruments are adjusted to zero and ensure that all wiring is correct before the next debugging;
In the case of disconnecting the power supply of the main circuit, turn on the control circuit, operate according to the requirements, and check whether the contactor, indicator light and push-twist switch are normal. Turn on the main circuit power, start the fan, observe the fan rotation direction is correct, the fan running 5 minutes, observe the fan air volume, motor temperature rise, working voltage, current is normal.
2) whether the pressure switches, pressure transmitters and differential pressure transmitters in different parts are normal.
3) instrument debugging:
The commissioning of the instrument cabinet and burner box should be completed before installation. After installation, the instrument cabinet and the burner operating cabinet in front of the furnace should be monotonically adjusted and connected with the "PLC" system of the main control cabinet and the computer. Confirm that no error can be debugged. After installation, add on-off signal to quick-cut valve, solenoid valve and electric regulating valve to check whether the valve body switch performance is correct and the signal feedback is correct, and set the switch limit in the correct position.