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Operation and maintenance manual of foam plate die

Views:2 Publish Time: 2021-11-10 : Louis Lu

Operation and maintenance manual of foam plate die

Operation and maintenance manual of foam plate die

1.  Die lip, choke rod, regulating system


A. die lip installation install the upper die lip on the upper die (3). First tighten the die lip slightly on the die with the upper die lip fastening screw (5).Install the upper die lip adjusting screw (2) so that its lower end is slightly in contact with the upper die lip, and fasten the upper die lip adjusting connecting screw (1) through the upper die lip adjusting screw on the die lip (4).When the opening clearance of the die lip reaches the required clearance, tighten the upper die lip fastening screw (5).

B. install the choke rod in the choke rod groove of the upper die, install the choke rod (13), assemble the choke rod adjusting screw bolt (12) through the screw hole of the choke rod, then successively assemble the lower pressure block (11), choke rod adjusting nut (9) and upper pressure block (10), and fasten the upper and lower pressure blocks on the die with screws. After the choke bar is completed, the upper die lip can be installed.

C. install the skin plate in the groove of the upper die lip (4). After installing the upper skin plate (6), tighten the screws. Install the lower skinning plate (7) into the clamping slot of the lower die (8) and tighten the screws. Please use the matching skinning plate (Note: there are 4 skinning plates, 2 are a set, the upper surface will be engraved with A. B signs, 2 letters a are a set, and 2 Letters B are a set.)

2.  Common problems and solutions in daily die production

Something went wrong

Check the cause


1.Uneven thickness   distribution or irregular extrusion, etc.

1Unreasonable heating temperature setting

As the temperature directly affects the flow pattern of   the melt in the die channel and the longitudinal thickness distribution of   the product, check whether the heating device and temperature control device   are damaged and whether the heating temperature in each area is reasonable.   Increase or decrease it slightly according to the production situation and   ensure the stability of the heating temperature.

2Wrong wiring or damaged temperature measuring device

Check whether the preset temperature is consistent with   the actual temperature. The temperature measuring device (thermocouple) shall   be inserted to the bottom and connected with the mold with thread; The   heating element with poor heating shall be replaced.

3Pressure fluctuation

Check the setting of upstream equipment (screen changer,   gear pump, distributor, etc.) and adjust the die after extrusion is stable.

4Uneven transverse thickness of products

Properly adjust the die lip adjusting device to make it   uniform.

5Die lip clearance is too small or too large

Adjust the fine-tuning screw according to the actual   product production.

6Dirt on die lip

The die lip clearance is very small. If the filter   screen is not clean or the shutdown time is too long, and the molten material   is oxidized and decomposed at the lip, it will cause impurities to block the lip   and affect the product quality. Therefore, the die lip should be cleaned in   time during production.

2.The surface of the product   is defective

1Excessive melt impurities

Clean the die head and connector again, replace the raw   material or install the melt filtration device.

2Impurities in the flow channel

If the equipment operates for a long time, the melt or   impurities will accumulate in the flow channel, affecting the melt flow and   product quality. The flow channel should be cleaned regularly. In normal   production, it is recommended to clean and maintain every six months to   prolong the service time of the die.

3The runner or die lip is scratched

If you can't handle it by yourself, please contact the   manufacturer. Serious damage must be returned to the manufacturer for   treatment.

4Peeling of chromium layer in runner

The long-term production or use of corrosive raw   materials may cause the electrodeposited coating to fall off and must be   returned to the manufacturer for treatment.

3. material leakage

1Inlet pressure exceeds mechanical limit

Check the extruder settings. Damaged or inaccurate   pressure sensors need to be replaced or recalibrated.

2The connecting screws are not tightened

Tighten the connecting screws again after heating, and   use uniform torque

3Uneven mounting surface

Clean the mounting surface again and level it with   grindstone if necessary.

4The assembly is not in place or the seal is damaged

Check the installation position of accessories, tighten   the connecting screws evenly, or replace with new seals.

Remarks: please pay attention to the maintenance of the mold. Please apply protective oil when not in use. Pay attention to the surface damage. The screws provided by our company are 12.9 screws, and the screws are filled with high-temperature lubricating oil.




3.       Operation steps

1 Mold installation

1. place the die head horizontally (front and rear, left and right directions) and adjust the center height to the appropriate size, and then fasten the trolley screw rod.

2.Generally, the top plate and backing plate of the side plate shall be removed before the die head is heated up (so as to finally fasten the large screws of the profile plate before startup).

3.Before the die head heats up, remove the 6 screws connecting the flange and the upper die, and do not remove the connecting screws between the flange and the lower die (so that the large screws of the profile plate can be locked before startup).


2 Temperature rise and insulation

4.Generally, when the die head is heated up, the temperature of the barrel and the die head heating area is initially set at about 100 --- 120 , and the high temperature is raised after holding for 2 hours. The barrel temperature is set as follows: barrel I 170 , barrel II 165 , barrel III 160 , barrel IV 155 , barrel V 150 , confluence core 145 (the barrel temperature is generally determined according to the plasticization degree of raw materials. If the plasticization is good, the temperature should be reduced, and if the plasticization is not good, the temperature should be increased accordingly)

5. die head temperature setting (the principle is that the temperature on both sides of the die head is slightly higher and the temperature in the middle is slightly lower).Die temperature reference is as follows:

6Zone 1, zone 2, zone 3, zone 4, zone 5, zone 6, zone 7 (zone 8-zone 9 are side plates)

7. 170 166 162 160 162 166 170 175 175

8.The oil temperature is generally 140-165 (depending on the foaming and discharging conditions of the board).

9.After the die head rises to high temperature, the large screws of the profile plate can be locked, and then the flange screws can be fixed. At the same time, adjust the parallelism and balance between the die head and the setting table, adjust the die gap according to the product size, and then install and lock the top plate and base plate of the side plate.


3 Die gap and setting die adjustment

10.Generally, the die gap shall be adjusted according to the ratio of 1:5. For example, for products with a thickness of 15mm, the die gap shall be generally adjusted to 3mm.And the middle is slightly smaller than the two sides by about 0.2-0.3mm.(the adjusting tool is a copper feeler gauge).

11.The height of the last section of the setting die (the section furthest from the die head) is generally consistent with the product thickness (it can be slightly smaller than 0.1-0.2mm).The third section is enlarged to 0.5mm, and so on.

12.After the above preparations, you can basically start the machine. Before starting the machine, fill some lubricating oil such as paraffin into the observation hole of the barrel to maintain the lubrication between the screw and the barrel.


4 Startup (relationship between current, extruder speed and feeding)

13.When the extruder is just started, the rotating speed is generally 6-8 revolutions, the feeding is added slowly, the current is maintained at about 80A, and the current can not be too high. When the raw material comes out of the die, slowly increase the extruder speed and feeding speed. After normal startup, the extruder speed is generally 18-22 revolutions, and the extruder current is maintained at 100A (relative to 70% of the rated current of AC motor).

14.When the molding of the product outlet is complete (the discharge is almost the same), pass the traction rope from the back of the tractor through the setting die to the die head, hang it in the middle of the product, and pull the product slowly backward with the aid of the tractor. At this time, the setting mold will not press the product temporarily. When the product is completely put into the tractor, lower the first and second sections of the setting mold, and add water to cool the product. In this way, the product will not be broken. Then slowly lower and press the third and fourth setting dies until the products are straightened and flattened. If the product is uneven as a whole, the traction speed shall be reduced, and if it is uneven locally, the corresponding adjusting screw shall be adjusted.(pay attention to the ratio of traction speed to product discharge speed at any time during operation, and adjust it timely according to the site conditions)


5 Shut down

Each shutdown operation is as follows: 1. Extrude the raw materials in the barrel and die with the shutdown material (keep the screw and die clean).2. Formwork removal - loosen the screws of the side plate and take out the side plate and splint (handle with care).The M36 screws of the profile plate (divided into left and right based on the feed inlet) are staggered and removed from the left and right.3. Lift the upper plate to the drag tray and check the mold cavity (whether there is material accumulation and scratch).4. Clean the mold cavity (oilstone, metallographic sandpaper and other tools) 5. Mold cavity maintenance (apply silicone oil or high temperature resistant oil).


6 Dear customer, the above are simple operation steps for reference. Please read it carefully. Commissioning and production are recommended to be operated by professionals. To achieve the harmony between raw materials - Formula - extrusion equipment - products - people.