(1) The outer surface of plastic pipes is rough
Adjust the process temperature: reduce the cooling water temperature, and the suitable cooling water temperature for P pipe is 20-25 ℃; Check the waterway for blockages or insufficient water pressure; Check if the heating coils such as the barrel and head are damaged; Adjust the inlet flow rate of the fixed diameter sleeve; Consult the raw material supplier for the parameters of this batch of raw materials; Check the temperature of the mold core. If it is higher than the temperature of the mouth mold section, lower the temperature of the core; Clean the mold.
(2) There are grooves on the outer surface of plastic pipes
Adjust the water outlet pressure of the fixed diameter sleeve to ensure a balanced water output; Adjust the nozzle angle inside the vacuum shaping box to ensure even cooling of the pipes; Check if there are any debris, burrs, etc. on the hardware of the mouth mold, fixed diameter sleeve, cutting machine, etc.
(3) There are grooves on the inner surface
Check if there is water in the inner tube. If there is water, pinch the tube blank of the just outlet mold tightly to seal its inner cavity; Reduce the internal temperature of the mold; Clean and polish the mold.
(4) There is a shaking ring inside the pipeline
Adjust the water outlet of the fixed diameter sleeve to ensure even water outlet; Adjust the vacuum degree of the second chamber to slightly higher in the rear chamber than in the front chamber; Check if the vacuum sealing gasket is too tight; Check if there is any shaking phenomenon in the traction machine; Check if the discharge of the host is uniform.
(5) Without vacuum
Check if the inlet of the vacuum pump is blocked. If it is, use a needle to clear it; Check if the vacuum pump is working properly; Check if there is any air leakage in the vacuum pipeline; Check if the small hole in the middle of the clamping screw of the core mold is blocked. If it is, use a thin iron wire to clear it.
(6) The outer diameter of the pipe exceeds the tolerance
Adjusting the vacuum degree can change the size of the outer circle; Adjusting the traction speed can change the size of the outer circle; Correct the inner hole size of the sizing sleeve.
(7) The roundness of the pipe exceeds the standard
Adjust the angle of the nozzle in the vacuum shaping machine and spray box to ensure even cooling of the pipes; Check the vacuum shaping machine, the water level height in the spray box, and the pressure on the water pressure gauge to ensure that the spray volume is large and strong; Check the water temperature of the vacuum molding machine and spray box. If it is greater than 35 ℃, a chilled water system or an additional spray cooling box should be installed; Check the waterway and clean the filter; Adjust the process; Check and correct the roundness of the inner hole of the fixed diameter sleeve; Adjust the pipe guide clamping device to correct the ovality of the pipe.
(8) Uneven wall thickness of pipes
Adjust the wall thickness on the mold; Adjust the angle of the nozzle in the vacuum shaping machine and spray box to ensure even cooling of the pipes; Adjust the water outlet of the fixed diameter sleeve to ensure even water outlet; Open the mold, check if the screws inside the mold are loose, and tighten them again.
(9) High plasticization temperature
Adjust the process; Adjust the heating temperature of the mold core and ventilate and cool the inside of the mold.
(10) Inaccurate cutting length calculation
Check if the measuring wheel is tightly pressed; Check if the measuring wheel is swinging and tighten the fixing bolts of the measuring wheel frame; Check if the travel switch of the cutting machine is damaged; Check if the rotary encoder is damaged; Whether the wiring of the rotary encoder is soldered off (whether the contact of the aviation plug socket is good); Each individual machine casing (PE terminal) should have its own grounding wire reliably grounded to one main grounding point, and this grounding point should have a grounding pile that meets electrical grounding requirements. It is not allowed for each individual machine casing (PE terminal) to be grounded in series, otherwise interference pulses will be introduced, causing inaccurate cutting length.
(11) Co extrusion identification strip issue
Co extrusion identification strip diffusion: generally caused by improper selection of co extrusion materials used by users. Special materials such as PE should be used, and if necessary, the temperature of the extrusion section can be reduced.
Co extrusion identification strip cannot be squeezed out: If there is no co extrusion identification strip after 2 hours of startup, it is generally caused by the screw of the co extrusion machine retreating; Remove the screw and tighten it again.
The co extrusion identification strip is too thin or too wide: usually caused by the mismatch between the extrusion amount of the co extrusion machine and the traction speed of the pipe. The frequency of the co extrusion machine frequency converter should be adjusted or the traction speed should be changed to match the speed of the two; The second reason is that the cooling water jacket in the feeding section of the co extrusion machine is not filled with cooling water.
Sometimes there is no identification strip for the co extrusion machine: it is usually due to uneven co extrusion material feeding at the feeding port of the co extrusion machine. The water flow of the cooling water jacket at the feeding port should be checked and an appropriate co extrusion material particle size should be selected (generally requiring particles<Φ 3 × 3mm).