FAQ

question: oil pump sound too big after period production

daya machinery:  possible reason as below:

1. filter net has dirty.   solution: clean filter and change the hydraulic oil.
2. quality of sutionoil pipe is poor.  solution: check and change the suction oil pipe, filter net, hydraulic oil.
3. oil pump worn out .   solution: check and change if need

Question: temperature control failure

daya injection molding machine:  below possible reasons:

1. temperature control gauge is wrong.   solution: measure it by multimeter, change it if need
2. thermocouple is wrong.  solution: check the thermocouple of each heating section.  and change it if damaged
3. during charging, the screw and barrel are too hot to make the heating band broken.    solution:  meansing the heating band, change it if damaged

Question: machine work without force

daya injection machine: below possible reasons:

1. The relief valve blocked and often release oil .    solution: Check relief valve and Clean the valve
2. oil seal ring wear out .  solution:Check each oil cylinder, piston and oil seal ring or change
3. oil pump wear out.   solution: remove oil pump, check and change if need
4. preportion valve wear out.   solution: Check and Change proportion valve

question: no movement of machine

daya machine: below possible reasons:

1.  Amplificatory board no output.  solution: Measure output voltage of amplificatory board, and if no voltage, change the board.
2. fuse burn out.  solution: Check or change connecting fuse
3. oil pump’s motor rotation reversion.  solution: Exchange two phase
4. join device between oil pump and motor.   solution:After switch off change it
5. pressure valve blocked no pressure.  solution:Clear pressure valve, and change hydraulic oil and filter
6. 24V power wire broken.  solution:Measure and reconnect them
7. oil pump motor burn out and not start.   solution: Measure motor winding by multimeter and Change motor
8.  Oil pump is wrong, not retraction oil and increase pressure.   solution:remove oil pump, check and change it if need
9. Be wanting one phase at three-phase of electricity power.   solution:  check the main electric supply.

question: the action of machine too slow

daya injection machine: below possible reasons:

1. current set fail.   solution: Check current of flow and pressure and reset it
2. flow valve blocked.  solution:Clean flow valve
3. system pressure too low.  solution:  adjust system pressure

question: the injection machine shakes greatly

daya injection molding machine: below possible reasons:

1. fixed bolt of main motor loose.   solution: Tighten the bolts
2. body and guide of machine not leveling.    solution: Adjust the parallelism and horizontal.

question: Flow and pressure do not proportion

daya injection machine: possible reason as below:

1. voltage transformer connected bad.    solution: Measure transformer output by multimeter or reconnect it
2. wiring wrong.   solution: Measure connecting wire point by multimeter and reconnect it
3. number control grid weld fails .  solution: Measure connecting wire point by multimeter and weld it again.

Question: pressure and oil temperature too high

DAYA injection machine: there may be below possible reasons:

1. the hydraulic oil leveling inside the oil tank is too low.  solution:  filling enough hydraulic oil
2. the pressure is too high at no load condition.  solution： set pressure at 1.5Mpa at no load
3. water temperature is too high.  solution: Clean water scale and add water flow capacity or clean water

Question: full automatic operation failure

daya injection molding machine:  possible reasons as below

1. sensor is failure or fixed bolts loosen.    solution：Fix the sensor’s bolt well or change it
2. time relay failure or damaged.  solution： Check time relay and change it
3. thermocouple connect poor or damage .  solution ： Change or reconnect it
4. Heating ring damaged   solution: Change it
5. temperature gauge damaged.   solution: Check and change it

Question: semi automatic operation failure

daya molding machine:

electricity switch or time relay no working .  solution: Find fault according to action diagram or change electricity part

question: the machine can only do injection only at semi-auto operation

daya injection machine: Injection time relay is wrong. solution: Check the time relay and change one

question: barrel temperature exceed setting value

daya injection molding machine:   there may be low possible reasons:

1. screw rotation speed too fast.  solution: Adjust the screw speed
2. backpressure too high.  solution: decrease the backpressure
3. screw and barrel worn.   solution ： check and change
4. temperature setting improper.  solution: check and reset
5. the temperature at plastic cutting too high (specially ABS).   solution: Adjustment screw rotation peed and backpressure lower

Question: no injection at semi automatic operation

Daya injection machine ：  there are possible reasons:

1. The platen do not clamp to end at the carriage forward end.  solution：check the limit switch and connect the wire
2. wire broken.  solution: reconnect it
3. relay inserted wrong.  solution:   the relay insert correctly
4. no zero on the PLC.  solution:  reset the 0 position on the panel.
5. time relay is damaged.  solution: change it.

question: screw can’t mix color well

daya injection machine:  possible reasons as below:

1. material has problem.  solution: change it.
2. temperature too low.  solution: increase the heating temperature
3. back pressure too low.   solution: increase it
4. screw rotating speed twoo low.   solution: add the speed
5. diffuse quanity of oil is too small.  solution:  add them

Question: black points on the product

Daya machinery:  there may be below reasons:

1. There are old material left over on the screw.   solution: Clean and polishing screw
2. There are some old material left over on the barrel, or accessory hasn’t clean.  solution: Clean accessory and polishing barrel
3. Some parts are dirty and rust such as suck off ring, thrust ring screw tip, material cylinder.   solution：Clean, polish and change them
4. Have old material left over on the flange and nozzle.  solution: Clean, polish and change them
5. Temperature is too high, backpressure of charging is too high.   solution: Check each section temperature, and fall down, decrease backpressure.
6. raw material are dirt.  solution: check and change them

question: back-pressure not set at plasticizing

daya machinery:

Bad back-pressure valve.  solution: Clean back pressure valve or change it

Question: The noise of beginning plasticizing is loudly

daya machinery:

1. Exchange fast/low speed over fast.   solution: Raise backpressure or increase injection section step  or Raise holding pressure, add plasticizing time

Question: The noise of injection loudly at beginning injection

daya machinery:    there may be below reasons:

1. beginning speed of injection too quick.  solution： Adjustment setting value on the menus
2. backpressure too high.   solution: decrease the back pressure
3. there is air inside the oil circuit.   solution:  exhaust the air.

question: injection machine’s carriage do not moves

DAYA MACHINEY: there may be below reasons:

1. .piston bar broken.   solution: Remove locking nut and change piston bar
2. direction valve of carriage moving is no working.   solution: Check and clean it if blocked
3. Electricity wire disconnected.   solution: change the coil of solenoid valve or connect wire

Question: injection machine no charge

DAYA MACHINEY:  there may be below reasons:

1. back-pressure valve damaged or back-pressure too high.  solution: Change backpressure valve or adjust pressure lower
2. the cooling water of barrel are not enough, temperature of hopper is too high.   solution:Clear plastic block feel in the hopper, in the barrel, increase cooling water capacity.
3. no material in the hopper.   solution: Check and charge the material
4. screw and barrel wore out.   solution: Check and change it

Question: machine can’t inject

DAYA MACHINERY:

1. Coil of solenoid valve is burned.  solution:  check and change it.
2. valve core blocked by dirty thing.  solution:  clean it or change the solenoid valve
3. pressure of injection is too low.    solution: set injection pressure
4. the temperature of material barrel is too low.    solution: check, change fuse and reset temperature of material barrel
5. piston seal of injection cylinder is damaged.   solution: check seal ring and change it
6. shut off ring broken .   solution:  check and change the ring
7. nozzle blocked.   solution: clean nozzle or change it

Question: The hydraulic motor oscillating at plasticizing

DAYA MACHINERY: there may be below reasons:

1. gearing damaged.  solution: change gearing
2. setting clearance between gearing improper.  solution：Check transmission shaft shaking or not at plasticizing, reset the clearance.
3. screw distortion。 solution:If screw bend change screw
4. copper bushing of carriage wear out heavily.  solution: Check copper bushing and leader and change them

Question: the sound is too high when opening mold

DAYA MACHINERY:  there may be below possible reasons:

1. Lubricates of clamping structure are worse.  solution: Check steel sleeve and shaft with locking, if wear out, change it.
2. clamping force is too large.   solution: Adjust suitable clamping force.
3. Parallel between fixed mold platen and moving platen platen is bad. Set moving platen and improve mold parallelism
4. exchange time is too short from low  speed to quick speed. Solution: add Propriety opening mold time

Question: can’t adjust mold height

DAYA MACHINERY: there may be below reasons:

1. The clearance between pressing lid of adjusting nut and nut is too small. solution: Adjustment the clearance between lid and nut
2. screw thread of mold-adjust nut gnaws dead.   solution: Change nut, or repair the screw
3. the slider of moving platen moves too heavy.  solution: Adjustment moving slider  again
4. The motor used for adjusting mould does not work.  solution: Check the valve of  mold adjustment, if bad change or repair it
5. proximity switch, relay and contactor are burned.   solution: Check 3-phase voltage, and change these parts
6. the wire interrupt or connect bad.  solution: Check control wire and each contact, then reconnect

Question:Can’t control to open mould fastly or slowly

DAYA MACHINERY:The Relay on program plate is wrong.  Solution: Change relay

Question: mold clamping blocked

DAYA MACHINERY: there may be air in the oil circuit.  solution:  exhaust the air

Question:only have speed and no pressure at clamping

DAYA MACHINERY: High pressure stroke switch does not work.   solution: Check the switch and repair or change it

Question: high pressure mold clamping not work

DAYA MACHINERY: it is because the set of mold height improper.  solution: Adjustment moving platen forward

Question: the moving mold platen don’t close during mold closing

DAYA MACHINERY: Wire connecting error.   solution:Check and reconnect them

Question: the mold auto open slowly at other operation after clamping

DAYA MACHINERY: Opening mold valve is leakage.  Solution: Change opening mold valve

Question: big oil pump do not unload

DAYA MACHINERY:  there may be below possible reason:

1. hydraulic valve blocked.  solution: Clean pressure valve or reconnect
2. unloading time too short.  solution: Extend unloading time
3. Speed and pressure of unload too small or nothing.    solution:Raise speed and pressure of discharge

Question: Fault of adjustment mould counter

DAYA MACHINERY: there are possible below situation:

1. proximity switch is bad.  solution: Change switch, setting position
2. adjusting mold travel time too short.   solution: Adjusting molds stroke time.
3. adjustment nut blocked.  solution: Change burned parts and set clearance of adjustment mold nut

Question: creeping of opening and closing mold

DAYA MACHINERY:  there may be 3 possible reasons.

1, Leader supported moving platen and tie bars wear out heavily. solution: Change wears out parts and often lubricate machine.

2, Level and vertical between two platens.   solution:  Setting leader levelly.  or Adjust slide of moving platen to make tie bar straight.

3.the opening mold speed and pressure setting data are wrong.  Solution: Exhaust air gas. or Adjust flow and pressure proportional.  or Set current data of proportion valve.

Question: machine can’t make the good product stably

DAYA MACHINERY:

In a stable production cycle, if the quality of the finished product is unstable, which may be caused by wear or improper adjustment of the mechanical parts.

1. Wear of screw, check ring and barrel.
2. The inner seal of the injection cylinder is damaged and internal leakage occurs.
3. The temperature control of the heating cylinder is unstable.
4. The pressure and speed control are partially abnormal.

Abnormal noise occuring indicating that parts are damaged or improperly adjusted. The cause should be repaired according to the location of the noise.

1. The hydraulic oil in the fuel tank is insufficient. The suction of the oil pump or the dirt of the oil filter will cause the oil pump to be short of oil, causing the air bubbles in the oil to leak and hit the blade to generate noise. The solution is to check the oil quantity and prevent the air from being inhaled. Clean the oil filter.

2. The viscosity of the hydraulic oil is high, and the flow resistance is increased. It is necessary to replace the suitable hydraulic oil.

3. Due to the damage of the bearing or blade of the oil pump or motor, the concentricity deviation of the coupling causes noise, and the concentricity or replacement parts must be adjusted.

4, the directional valve reaction is not effective but the function is still, such as valve core wear, internal leakage, burr blocking, movement is not flexible, solenoid valve failure due to insufficient current will also produce noise. The solution is to clean the valve core, the valve core must be replaced with new parts, and the current must be stable and sufficient.

5. The hydraulic components are damaged or the oil pipelines are blocked, causing noise when the hydraulic oil flows at high speed.

6. If the mechanical part is faulty, the bearing is worn or the machinery lacks lubricating oil or the parts are loose, the reason should be found to tighten or replace the parts to ensure sufficient lubricating oil.

An abnormal rise in oil temperature may be caused by an abnormality in the cooling system or high heat generated by the hydraulic components during operation.

1, the cooling system is not normal

1) Insufficient supply of cooling system, such as insufficient water opening, insufficient water pressure or pump flow does not meet the needs.
2) Blockage of pipes, such as filters, cooling towers or water pipes.
3) The cooling water temperature is too high, such as the cooling tower cooling capacity is insufficient, or the damage or the temperature is too high.

2, the hydraulic system produces high heat

1) The oil pump is damaged, and internal parts are worn at high speed to generate high heat.
2) The pressure regulation is not proper, and the hydraulic system is in a high pressure state for a long time and is overheated.
3) Internal leakage of the hydraulic components, such as damage to the directional valve or damage to the seal ring, causes heat to be generated when the high pressure oil flows through the small space.

(1) According to different load requirements, always check and adjust the pressure of the relief valve to make it just right.

(2) Reasonable selection of hydraulic oil, especially oil viscosity, when conditions permit, try to use a lower viscosity to reduce viscosity friction loss.

(3) Improve the lubrication condition of moving parts to reduce friction loss, which is beneficial to reduce working load and reduce heat generation.

(4) Improve the assembly quality and accuracy of the hydraulic components and hydraulic system, strictly control the matching clearance of the fittings and improve the lubrication conditions. The sealing material with low friction coefficient and the improved sealing structure are used to reduce the starting force of the hydraulic cylinder as much as possible to reduce the heat generated by the mechanical friction loss.

Question: why machine alarm – high hydraulic oil temperature

1.  The fuel tank volume is too small, the heat dissipation area is insufficient, and the cooling device has a small capacity.
2. The dosing pump oil supply system that selects the pump capacity according to the fast-forward speed, during operation, most of the excess flow will overflow from the overflow valve under high pressure and generate heat.
3. The unloading circuit in the system is faulty or the unloading circuit is not set. When the pump stops working, the oil pump cannot be unloaded. The entire flow of the pump overflows under high pressure, causing overflow loss and heating, resulting in temperature rise.
4. The system piping is too long and too long, too much bending, partial pressure loss and large pressure loss along the path.
5. The component accuracy is insufficient and the assembly quality is poor, and the mechanical friction loss between the relative movements is large.
6.  The matching clearance of the fittings is too small, or the wear is too large, resulting in excessive clearance, and the internal and external leakage is large, resulting in volume loss, such as the volumetric efficiency of the pump is reduced, and the temperature rise is fast.
7. The hydraulic system working pressure is adjusted much higher than the actual needs. Sometimes it is necessary to increase the pressure to work because the seal is too tight, or because the seal is damaged or the leak is increased.
8. The temperature of the gas and working environment is high, causing the oil temperature to rise.
9. Selecting the viscosity of the oil is improper, the viscosity is large, the viscous resistance is large, and the viscosity is too small, the leakage is increased, and both cases can cause the heat rise.

Quesiton: Injection moulding machine can’t close the mold

DAYA MACHINERY:

1.  check the front travel switch of safety door and repair it.
2. check the 24V5A power in the electric box, replace the insurance and the power box.
3.  check whether the spool is stuck, clean the spool.
4. check the I/O board has output or not,weather the magnetic valve is open or not.
5. check whether the hydraulic safety switch is closed, whether the mechanical lock rod is opened or not.

solution:

 1): starting speed is slow, check the screw damping ,wheher it is too big, adjust to use  screw with small damping hole.

2): damping screw middle hole too big, check the Y screw hole damping is too large or not,change for damping nail with smaller center hole  .

Handling method:

1)check whether the lubricating oil pipe is cut off , if so, reconnect the tubing pipe.

2): small amount of lubricating oil, increase lubricating oil amount , add once at 50 mold open-close circle,or manually add lubricating oil.

3): clamping force over large, check whether the mold needs large clamping force, lower the clamping force.

4): the current fluctuation of the amplifier board, check whether the current parameters meet the acceptance criteria, re adjust the current value.

5): parallelism error,use  indicator to check head board parallelism to make sure it’s  greater than the acceptance criteria or not; adjust the parallelism.

Processing method:

1): increase the speed of the mold open-close, the pressure and flow is too small, not adjusted, check the speed of the mold open-close, the pressure is appropriate or not, increase the pressure and speed of the mold open-close.

2): The electronic ruler in clamping unite is zero change, check the ruler,whether it is stop in the zero position or not, re adjust the electronic ruler into zero position.

3) check whether it is anti- hinge.