Common problems and solutions for PET preforms injection molding machine, Part 4.

Common problems and solutions for PET preforms injection molding machine, Part 4.

 

9, The preforms cavities are not injected fully, and melting strips on the preforms.

A, Causes:

   1, Air extraction function is not working well

   2, Injection direction is not straight

B, Solutions:

   1, Increase the air extraction.

   2, Clean the injection mold

   3, Slow down the injection speed

   4, Fix the mold injection holes

10, The preforms uneven thickness

A, Causes:

   1, Molds manufacturing technique is not good

   2, Injection hole is not in right position

   3, Injection pressure is too high

   4, Injection molds core is not in the right place

B, Solutions:

   1, Fix the molds

   2, Increase the material temperature

   3, Reduce the injection pressure

   4, Make good quality molds

http://www.sinobema.com/Difference-between-bottles-of-pure-water?article_id=188

From Sino Beverage Machinery Co., Ltd China
施诺机械设备有限公司中国
sinobema@gmail.com
www.sinobema.com 

www.sinobeveragemachinery.com
WhatsApp: 0086 137 28668423

Common problems and solutions for PET preforms injection molding machine, Part 3.

Common problems and solutions for PET preforms injection molding machine, Part 3.

6, Air bubbles in the PET preforms.

A, Causes:

   1, PET granules are not dried enough.

B, Solutions:

   1, Enhance the drying process

   2, Increase the material temperature

   3, Slow down the rotary screw

7, Irregular ring groove in the PET preforms.

A, Causes:

   1, Condensate water inside the preforms molds.

B, Solutions:

   1, Dry the factory workshop

   2, Increase the temperature of the cooling water

   3, Wipe dry the internal and external parts of the injection molds.

8, Cracks on the injection position of the preforms.

A, Causes:

   1, The hot runner is not straight with the injection nozzle.

   2, Material back to the injection nozzle

   3, Injector area is too hot

B, Solutions:

   1, Fix and repair the molds

   2, Fix and repair the injection nozzle

   3, Increase the cooling time

http://www.sinobema.com/Difference-between-bottles-of-pure-water?article_id=186

From Sino Beverage Machinery Co., Ltd China
施诺机械设备有限公司中国
sinobema@gmail.com
www.sinobema.com 

www.sinobeveragemachinery.com
WhatsApp: 0086 137 28668423

Common problems and solutions for PET preforms injection molding machine, Part 2.

Common problems and solutions for PET preforms injection molding machine, Part 2.

3, Clear/transparent PET preforms change into non-clear preforms

A, Causes:

   1, the temperature for the molds-separating is too high

B, Solutions:

   1, Enhance the cooling water

   2, Increase the cooling time

   3, Change the injection time

4, Fogy shadow appears at any side of the preform.

A, Causes:

   1, Holding pressure is too high.

   2, Bottom injection hole is not in the center.

B, Solutions:

   1, Reduce the pressure

   2, Fix the molds bottom parts.

5, Silver waves or a little-yellow-colors on the PET preforms.

A, Causes:

   1, Plastic decomposition

B, Solutions:

   1, Reduce the dryer temperature, and increase the drying time.

   2, Adjust the injection speed

   3, Reduce the material temperature

   4, Reduce the temperature on the hot nozzles. 

http://www.sinobema.com/Difference-between-bottles-of-pure-water?article_id=185

From Sino Beverage Machinery Co., Ltd China
施诺机械设备有限公司中国
sinobema@gmail.com
www.sinobema.com 

www.sinobeveragemachinery.com
WhatsApp: 0086 137 28668423

Common problems and solutions for PET preforms injection molding machine, Part 1.

PET bottle means the bottle contains a kind of chemical plastic which has been called “polyethylene terephthalate”. And we just call it PET bottle. PET is a kind of polymeric substance which is made by chemicalizing Terephthalic acid Ethylene glycol.

PET plastic is featured by light weight, high-transparency, and not easy to be broken. And PET can also stop the CO2 gas, which can keep the CO2 gas for the carbonated drinks.

PET bottles have been widely used in bottling, chemical, cosmetic industry.

PET bottles are normally made from a kind of PET plastic tube, and we call it PET preform, which is made by PET preforms injection molding machine.

Here are the common problems and solutions for the PET preforms injection molding machines.

Common problems and solutions for PET preforms injection molding machine, Part 1.

1, PET preforms’ bottom white/milky color.

A, Causes:

1.      Temperature for the hot runner tunnel is not enough.

2.      Material temperature is not enough.

B, Solutions:

1.      Enhance the heat-isolation device. To keep the temperature.

2.      Increase the temperature for the milky color part.

3.      Increase the material temperature properly.

4.      Speed up the injection process.

5.      Reduce the pressure.

6.      Slow down the cooling water speed.

2, PET preforms not clear/transparency.

A, Causes:

1.      PET granules are not dry enough.

2.      PET granules are not plasified enough.

3.      PET preforms are too thick.

4.      Preforms are not cooled enough.

5.      Other materials are mixed into the PET granules.

6.      Material temperature is too low.

B, Solutions:

1.      Make sure the granules been dried for at least four hours.

2.      Increase the granules temperature.

3.      Increase the rotary speed of the injection screw.

4.      Make sure the water contains to be less than 0.02% under the temperature of 165 degrees.

5.      Enhance the cooling water.

6.      Reduce the thickness of the preforms.

http://www.sinobema.com/Difference-between-bottles-of-pure-water?article_id=184&pagenum=all

From Sino Beverage Machinery Co., Ltd China
施诺机械设备有限公司中国
sinobema@gmail.com
www.sinobema.com 

www.sinobeveragemachinery.com
WhatsApp: 0086 137 28668423

Debugging for the 3-in-1 bottle washing filling capping machine.

Sudden shutdown

Before this sudden shutdown, all parts of the machines are all working well.

And, at the same time, the washing filling and capping functions are all available if the machine is working on “Manual” model.

One the auto model is on, the machine will be shut down automatically, all parts not moving at all.

Just the power is on.

Normally, there will be two reasons for this kind of situation.

Both of them are designed, for machinery protection.

1.  Water level sensor is not working or damaged.

There is a simple water level sensor in the water tank on the top of the filling part, which is used for controlling the pump.

When the sensor reads that the water level is low, then it will send a signal to the PLC, and PLC will start the pump to get more water from the big water tank into the small water tank on the top of the filling part.

If there is no water coming in, and the water tank will be empty.

Then, the PLC will shut down the machine, just on the purpose of protecting the machine. Because filling without machine is wasting of both power and bottles, and it may damage the machine too.

Then, if the water level sensor is not working or damaged, it will keep sending wrong signal to the PLC, then PLC will keep shutting down the machine.

Is so, only need to replace the damaged water level sensor, then the machine will work well again.

2.  Power phases are not enough.

The power system on 3-in-1 washing filling capping machine is designed as 3phase. (380V/50HZ, 3phase or 220V/60HZ, 3phase, or 240V/440V. it is different for different country).

No matter it is 380V, or 220V, it must be 3phase.

 

So, on the power system.

If you have only 2phase connected or only 1 phase connected, then the machine will not get enough power.

And the PLC will shut down the machine automatically too.

Then, you will have to check the power system and make sure that the 3phase connection is right.

http://www.sinobema.com/Difference-between-bottles-of-pure-water?article_id=161&pagenum=all

From Sino Beverage Machinery Co., Ltd China
施诺机械设备有限公司中国
sinobema@gmail.com
www.sinobema.com 

www.sinobeveragemachinery.com
WhatsApp: 0086 137 28668423

Maintenance for bottling machinery

For the modern bottling machinery, it is very important for the operators to do an excellent job in daily maintenance, which means almost like supplying energy to a human being.

The regular and correct maintenance means continuously energy supplying to the machines, and which can keep the machine running for longer time.

For a bottling factory, good maintenance saves cost and improves the efficiency.

 

Good and suitable preparation should be done for the daily maintenance, such as an professional engineer, enough operational tools.

Before maintenance, there are important jobs to be done:

1. Cut the power supply.

2. Shut the water supply.

3. Close the air supply and reduce the air pressure.

4. Prepare enough operational tools.

 

Here are some points for the daily maintenance.

1. The oil filter/separator should be checked every day before work. If there are too much water inside, then the water should better be removed. And the oil should be added for a normal and necessary level.

2. During the operation, the worker should strictly keep an eye on the mechanical parts, the moving parts etc. To see if there are abnormal situations.

3. All the screws and bolts should be checked and tightened normally and regularly.

4. The grounding wire should be checked to make sure it is connected right.

5. The liquid inside the pipelines should be all drained if the machine will be stopped for a long time.

6. Clean the machine very well after work. The water spot, the dust etc.

7. All seals, sensors, electrical parts should be checked regularly. 

http://www.sinobema.com/Difference-between-bottles-of-pure-water?article_id=160

From Sino Beverage Machinery Co., Ltd China
施诺机械设备有限公司中国
sinobema@gmail.com
www.sinobema.com 

www.sinobeveragemachinery.com
WhatsApp: 0086 137 28668423

Daily maintenance for stretch blow molding machine, Part 4

A. The stretching system.

The stretching cylinder lifts the stretching slider, which keep the stretching system on the rail, and in right working position.

1. The distance between the stretching cylinder and the rolling wheel should be checked every month, to make sure there are 0.1-0.2mm distance, then the rail will not be damaged easily.

2. Check regularly if the screws and bolts are fixed tight on the stretching cylinder.

3. Check regularly if the the solenoid and air tubes are leaking air.

 

B. The blowing nozzles and the seals

The small compensation holes on the blowing nozzles are used for making sure the pressure in & external the screws are the same.

The blowing nozzles should be checked regularly, and the damaged or worn out seals should be replaced.

C. Cooling water circulating.

The flow quantity of the cooling water should be checked regularly to make sure it can provide enough cooling water to the molds.

The filter and water tank inside the chiller machine should be check every month too.

 

D. Air supplying system

This system is working for handling and distributing the high pressure air

The air pressure indicator on the control panels should be checked often to see if the pressure is right.

The water inside the oil filter should be drained every week.

 

E. Lubricating system

The external parts of the lubricating system should be cleaned often.

The lubricating oil quantity should be checked every day to make sure there are enough lubricating oil or butter there.

All necessary parts should be lubricated regularly. 

http://www.sinobema.com/Difference-between-bottles-of-pure-water?article_id=148

From Sino Beverage Machinery Co., Ltd China
施诺机械设备有限公司中国
sinobema@gmail.com
www.sinobema.com 

www.sinobeveragemachinery.com
WhatsApp: 0086 137 28668423

Daily maintenance for stretch blow molding machine, Part 3

Preforms transporting system

In the exit of the heating oven, the heated preforms will be picked by the star wheels.

Then, the heated preforms will be clipped by a mechanical clip (smaller cylinder with jaw normally), and then be transported to the mold.

 

The preforms clips should be cleaned regularly.

The mechanical clip should be checked regularly to see of any of them are damaged or deformed.

Molds opening & closing system

1. Opening & closing arm. It is used for opening and closing the mold rack to open an close the two parts of the molds.

Check regularly to see of the arm is not fixed tight.

Lubricate the necessary connection part, and make good protection. Lubricant oil or butter are fine.

 

2.  Cam guide. There are two sets of cam sticks which are used for lock or unlock the mold rack. A big cylinder is used there to set up the suitable location of the mold rack and then open and closet the mold rack.

The rotary axis should be lubricated regularly .

The drive bearings should be lubricated regularly.  

Check the buffer device for the opening and closing device.

Check all connections and joints to make sure they are fixed tightly.

 

3. When the mold is closed and locked, there will be around 0.25-0.35mm gaps between the two parts of the mold. The blowing process will close that gap by the blowing pressure by a compensation way. Then, the pressure will be the same in both internal and external parts.

all necessary parts should be lubricated, such as the mold, the mold rack, the transporting stick, the buffer device, the guide rail etc.

http://www.sinobema.com/Difference-between-bottles-of-pure-water?article_id=146

From Sino Beverage Machinery Co., Ltd China
施诺机械设备有限公司中国
sinobema@gmail.com
www.sinobema.com 

www.sinobeveragemachinery.com
WhatsApp: 0086 137 28668423