Cold chamber machines are mainly used to produce die castings of alloys such as copper, aluminum and magnesium (thick wall) with higher melting points. Hot chamber machines are used to produce die castings of alloys such as zinc, tin, lead and magnesium (thin wall) with lower melting points. Compared with the cold chamber machine, because the injection chamber of the hot chamber machine is directly immersed in the alloy solution, the pouring operation can be omitted, so the working cycle is short and the work efficiency is high.

In order to ensure the normal operation of the die-casting machine, scientific maintenance work should be carried out while using it correctly [5]. Therefore, it is necessary to formulate the operating procedures and maintenance management system of the machine according to the requirements of the manual and relevant regulations, especially the safety regulations. A dedicated person shall be responsible for their implementation and conscientious implementation, and illegal operations are strictly prohibited. (1) Clean the debris on the machine and the dust and dirt on all sliding surfaces, lubricate the non-automatically lubricated sliding friction surfaces, and check to maintain the normal amount of oil in the lubricating oil tank;

(2) Inspection Check whether the liquid level and pipeline in the hydraulic oil (liquid) tank are leaking, and whether the connecting fasteners are loose;

(3) Check whether the pressure gauge indication is normal, safety devices and strokes Whether the switch is normal;

(4) Check whether the pressure of the hydraulic system, hydraulic oil (liquid) temperature and color are normal;

(5) Check whether the automatic lubrication system is working normally, especially It is the lubrication condition of the toggle pin sleeve;

(6) Check the damage of the pressure chamber and punch, and clean and lubricate them in time;

(7) Check whether the cooling system is normal;< /p>

(8) Check whether there is any abnormal vibration and noise during operation of the machine, and deal with it in time. (1) Clean the dirt on the machine, paying special attention to the toggle part of the mold closing mechanism;

(2) Keep sufficient lubricating oil in the lubricating oil tank, and check the lubrication function of the lubrication system;

(3) Check whether the safety protection device and travel switch are normal, repair and tighten them in time;

(4) Check and tighten each connecting fastener;

( 5) Check whether there is leakage in the hydraulic system and the pressure change of the nitrogen-filled accumulator (whether there is air leakage);

(6) Check whether the injection position and the position of the large lever nut are consistent with the set position. Change and adjust in time;

(7) Check the tightening of solenoid valves, operating buttons and other components. (1) Clean the machine more thoroughly;

(2) Clean the filter element;

(3) Check whether the gap between the big bar and the guide bush is normal, and whether the big bar and Check whether the guide rail is strained. If it is strained, it should be smoothed with a whetstone in time;

(4) Comprehensively check and tighten the connecting fasteners of the hydraulic cylinder and hydraulic pipeline (including the fixation of the accumulator) ;

(5) Check the sealing condition of the electrical box, control box, etc., clean the dust attached inside, and tighten the components and wire connections;

(6) Check or replace Damaged wires and components;

(7) Check the lubrication function of the lubrication system;

(8) Check the fastening screws that fasten the large bar nuts of the machine's fixing plate;

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(9) After starting the machine for the first time or 300 hours after the overhaul, the filter element should be cleaned and replaced, the hydraulic oil (liquid) should be re-filtered (the degree of filtration should be as specified in the machine manual), and the machine's oil tank should also be cleaned Clean it again, and then add filtered hydraulic oil (fluid); after every 3,000 to 4,000 hours of operation, check the quality of the hydraulic oil (fluid) before re-filtering and adding it, otherwise new hydraulic oil (fluid) should be replaced; The hydraulic oil (liquid) pollution level limit is VAS II, and the comparative system is NAS level 8.

Common faults and troubleshooting of die-casting machines Causes and troubleshooting methods ① Incorrect steering of the hydraulic pump

② Improper adjustment or damage of the relief valve

③ Hydraulic pump failure

④Large leakage inside and outside the pipeline

⑤Insufficient oil (liquid) suction (low oil/liquid level, blockage or air leakage in the oil/liquid pipe) ①Adjust the motor steering

②Re-adjust or replace new valves

③Repair or replace

④Inspect pipelines and components

⑤Add oil (liquid) and inspect Oil suction (liquid) pipeline ①The oil (liquid) level in the oil (liquid) tank is too low and the suction oil (liquid) is insufficient

②The hydraulic pump is faulty or the pump speed is low

③Pump, Large leakage of valves, hydraulic cylinders and pipelines

④Hydraulic control valve failure

⑤Hydraulic oil (liquid) viscosity is too high or too small

⑥ The oil return pipe sucks air above the liquid level

①Add oil (liquid) and inspect the oil suction (liquid) pipeline

②Inspect and replace the hydraulic pump and increase the pump speed

③Inspection of corresponding components and pipelines

④Inspection or replacement

⑤Replacement of hydraulic oil (liquid)

⑥Improve oil return to liquid level ① The cooling water is not turned on ② The cooler is fouled or malfunctions

③ There is too much useless high-pressure overflow during the circulation process

④ The internal leakage of the hydraulic system is too large

⑤Hydraulic pump failure

⑥Hydraulic oil (liquid) viscosity is too high or too small

⑦Insufficient heat dissipation in the oil tank ①Connect the cooling water

②Cleaning or maintenance , replacement

③Adjust working procedures, inspect and adjust the relief valve

④Inspect or replace components

⑤Inspect and replace hydraulic pump

⑥Change the hydraulic oil (liquid)

⑦Improve the heat dissipation components ①Hydraulic pump failure

②Relief valve failure

③Hydraulic pump motor is not coaxial

④The oil (liquid) level is low and the oil suction (liquid) pipe is blocked or leaking

⑤Hydraulic oil (liquid) contamination

⑥The system pipeline configuration is improper. Cause vibration or vibration ①Inspection or replacement

②Inspection or replacement

③Adjust coaxiality

④Add oil (liquid), inspect and absorb oil (liquid) pipeline

⑤Change the hydraulic oil (liquid)

⑥Arrange components and pipelines reasonably and improve the fixing method ①Air enters the hydraulic system

② Poor guidance and lubrication of hydraulic cylinders and moving parts

③Uneven hydraulic pump pressure and flow

④Hydraulic cylinder sealing resistance, bending, surface strain, etc.

⑤The opening of the control valve is too small or faulty

⑥The viscosity of the hydraulic oil (liquid) is too high ①Inspect and improve the system and discharge the air in the hydraulic cylinder

②Inspect and improve the guidance, and provide appropriate Lubrication

③See the troubleshooting methods in items 1 and 2

④Inspect the oil cylinder

⑤Adjust or inspect appropriately

⑥Replace the hydraulic pressure Oil (liquid) or increase the temperature of hydraulic oil (liquid) ① The guard door is not closed in place, and the interlock travel switch is not activated

②The mold closing valve is not activated

③The mold closing mechanism is activated Obstructed

④The mold core is not inserted in place and the travel switch is not moved

⑤Insufficient pressure in the hydraulic system ①Check and eliminate the fault of the guard door and the travel switch

②Check Check whether the solenoid valve is energized or stuck, repair it

③Check and clear the obstacles

④Maintenance

⑤See the troubleshooting method in item 1 ①Improper adjustment of mold closing and opening , the clamping force is too large

②There is adhesive on the parting surface of the mold, and the low-pressure protection switch works

③Insufficient pressure in the hydraulic system

④Mold closing Mechanism failure ① Adjust the opening gear appropriately

② Remove obstacles and check the protection travel switch

③ See the troubleshooting method in item 1

④ Maintenance ① Mold closing Not in place, the travel switch does not operate

②Slow injection valve failure

③The injection head is stuck ①See the troubleshooting method in item 7

②Inspection valve and control circuit

③Inspect or replace the injection chamber and injection head

No fast injection or the fast injection speed is insufficient or drops too much

① The quick-pressure injection valve is faulty and the transfer switch does not operate

②The accumulator pressure is insufficient, nitrogen leaks or the piston is stuck

③The quick-pressure injection valve opening is insufficient ①Inspection of the quick-pressure injection valve Valve and control circuit

②Inspect the accumulator or charge it with nitrogen

③Enlarge the opening ①Faulty booster valve

②The pressure of the hydraulic system is lower than the accumulator ①Inspect the boost control valve and control circuit

②See the troubleshooting method in item 1 ①Large leakage in the injection cylinder

②Seal between the booster piston rod and the floating piston Leakage or insufficient boosting stroke ①Inspect or replace seals

②Inspection

The boosting impact peak is too large or the boosting delay is too much

①Increase The opening of the pressure valve is too large

②The throttle of the boost control valve is too small ①Close the valve port appropriately

②Open the throttle port appropriately ①Injection valve failure

②The follow-up is not in place, and the return stroke switch does not act. ①Inspection of the injection valve and control circuit

②Inspection (see the troubleshooting method in ③ of 8) ①Injection chamber and injection cylinder piston The rod is not axial

②The injection chamber and the gate sleeve are not axial or there is a gap in the end face combination

③Insufficient cooling of the injection head

④Injection Chamber or injection head damage ① Inspect and adjust the coaxiality

② Inspect the coaxiality and end face of both

③ Improve the cooling system

④ Replace with new parts or repair