injection machine purchasing attention (1)

The five major hazards of excessive temperature rise of the iniksyon paghuhulma machine ay: thermal deformation of the machine, reduced oil viscosity, deformation of rubber seals, accelerated oil oxidation and deterioration, and reduced air component pressure.
One of the hazards: thermal deformation of the machine
The moving parts with different coefficients of thermal expansion in the hydraulic components are stuck due to their smaller fit gaps, causing malfunctions, affecting the transmission accuracy of the hydraulic system, and deteriorating the working quality of the parts.
Harm two: reduce the viscosity of the oil
Excessive temperature rise of the injection molding machine will cause the viscosity of the oil to decrease, increase the leakage, and the volumetric efficiency of the pump and the efficiency of the entire system will be significantly reduced. As the viscosity of the oil decreases, the oil film of the sliding valve and other moving parts becomes thinner and cut, and the frictional resistance increases, resulting in increased wear.
Hazard 3: Deformation of rubber seals
Excessive temperature rise of the injection molding machine will deform the rubber seals, accelerate the aging failure, reduce the sealing performance and service life, and cause leakage.
Hazard 4: Accelerate the oxidation and deterioration of oil
Excessive temperature rise of the injection molding machine will accelerate the oxidation and deterioration of the oil, precipitate bituminous substances, and reduce the service life of the hydraulic oil. The precipitates block the damping orifice and the slit valve port, causing the pressure valve to become stuck and unable to move, and the metal pipe is stretched and bent, or even ruptured.
Hazard 5: Leading to poor work quality of components
Excessive temperature rise of the injection molding machine will cause the quality of the parts to deteriorate. The dissolved air in the oil will escape, resulting in air pockets, which will reduce the working performance of the hydraulic system. The ideal working temperature of the hydraulic system should be between 45 degrees and 50 degrees. The reason is that the hydraulic system is designed according to a selected pressure oil viscosity.But the viscosity will change with the oil temperature, which will affect the work in the system. Components, such as oil cylinders, hydraulic valves, atbp., reduce control accuracy and response sensitivity, especially for precision injection machines. Kasabay nito, if the temperature is too high, it will accelerate the aging of the seal and cause it to harden and crack.If the temperature is too low, the processing energy will be consumed and the operating speed will be reduced. Samakatuwid, it is necessary to pay close attention to the working temperature of hydraulic oil. There are many reasons for the high oil temperature, but most of them are due to the failure of the oil circuit or the failure of the cooling system.
(1) According to different load requirements, frequently check and adjust the pressure of the overflow valve to make it just right.
(2) Choose hydraulic oil reasonably, especially the oil viscosity. When conditions permit, try to use a lower viscosity to reduce viscosity friction loss.
(3) Improve the lubrication conditions of moving parts to reduce friction loss, which is conducive to reducing work load and heating.
(4) Improve the assembly quality and accuracy of hydraulic components and hydraulic systems, strictly control the clearance of matching parts and improve lubrication conditions. The use of sealing materials with a small friction coefficient and improved sealing structure to reduce the starting force of the hydraulic cylinder as much as possible to reduce the heat generated by the mechanical friction loss.
(5) Add cooling devices when necessary. Karaniwang nagsasalita, most of the customers who have been engaged in the injection molding industry for many years have the ability to judge by themselves and choose the appropriate injection molding machine to produce. Gayunpaman, sa ilang mga kaso, customer ay maaaring kailanganin ang tulong ng tagagawa upang magpasya kung aling iniksyon paghuhulma machine upang gamitin, o kahit na ang customer ay maaari lamang magkaroon ng sample ng produkto o ideya, at pagkatapos ay tanungin ang tagagawa kung ang makina ay maaaring ginawa o kung aling modelo ay inihambing. Angkop.
Sa karagdagan, some special products may need special devices such as pressure accumulators, closed loops, injection compression, atbp., to be more efficiently produced. It can be seen that how to determine the appropriate injection molding machine to produce is an extremely important issue. The following information is provided for readers’ reference.
The important factors that usually affect the selection of an iniksyon machine include molds, products, plastics, molding requirements, atbp. Samakatuwid, ang sumusunod na impormasyon ay kailangang kolektahin o makukuha bago gumawa ng seleksyon:
Mold size (lapad, taas, kapal), timbang, espesyal na disenyo, atbp.;
The type and quantity of plastics used (solong hilaw na materyales o maramihang mga plastik);
The appearance size (haba, lapad, taas, kapal), timbang, atbp. ng iniksyon molded produkto; molding requirements, tulad ng kalidad kondisyon, Bilis ng produksyon, atbp.

After obtaining the above information, you can follow the steps below to select a suitable iniksyon paghuhulma machine:
1. Piliin ang tamang modelo: Ang modelo at serye ay tinutukoy sa pamamagitan ng produkto at plastic.
Dahil maraming mga uri ng iniksyon paghuhulma machine, it is necessary to correctly determine which injection molding machine or series the product should be produced from at the beginning, such as general thermoplastics or bakelite raw materials or PET raw materials. Color, two-color, multi-color, interlayer or mixed color, atbp. Sa karagdagan, some products require conditions such as high stability (closed loop), high precision, ultra-high shooting speed, high shot pressure, or rapid production (multi-loop), and suitable series must also be selected for production.
It can be put down: Determine whether the “Large Column Inner Distance”, “Mold Thickness”, “Mold Minimum Size” at “Die Plate Size” of the machine are appropriate according to the mold size to confirm whether the mold can be put down.
The width and height of the mold must be smaller than or at least one side smaller than the inner distance of the large column;
The width and height of the mold should be within the size range of the mold plate;
The thickness of the mold must be between the mold thickness of the injection molding machine;
The width and height of the mold must meet the minimum mold size recommended by the injection molding machine, and it will not work if it is too small;
3. Obtain: The mold and the finished product determine whether the “mold opening stroke” at “mold stroke” are sufficient to take out the finished product.
The mold opening stroke must be at least more than twice the height of the finished product in the direction of opening and closing the mold, at ang haba ng sprue ay dapat isama;
The stroke of the supporting mold must be enough to eject the finished product;
4. Kandado: Ang tonelada ng “clamping lakas” ay tinutukoy sa pamamagitan ng produkto at plastic.
Kapag ang raw materyales ay injected sa amag cavity sa mataas na presyon, isang mold-supporting pwersa ay binuo. Samakatuwid, the clamping unit of the injection molding machine must provide enough “clamping lakas” to prevent the mold from being opened. The calculation of the clamping force requirement is as follows:
Calculate the projected area of ​​the finished product in the direction of the switch mold from the appearance size of the finished product;
Die support force = projected area of ​​the finished product in the direction of the switch mold (cm2) × number of mold cavities × pressure in the mold (kg/cm2);
The pressure in the mold varies with the raw materials, generally 350～400kg/cm2 for raw materials;
The clamping force of the machine must be greater than the clamping force, and for the sake of safety, the clamping force of the machine is usually 1.17 times greater than the clamping force;
At this point, the specifications of the clamping unit have been preliminarily determined, and the tonnage of the model has been roughly determined, and then the following steps must be carried out to confirm which injection unit has a screw diameter that meets the requirements.
5. Full injection: Alamin ang kinakailangan “injection volume” mula sa bigat ng natapos na produkto at ang bilang ng mga mold cavities at piliin ang naaangkop na “screw diameter”.
To calculate the weight of the finished product, the number of mold cavities (one mold and several cavities) shall be considered;
For the sake of stability, the injection volume needs to be more than 1.35 beses ang bigat ng natapos na produkto, iyon ay, the weight of the finished product needs to be within 75% of the injection volume;
6. Good injection: The conditions such as “screw compression ratio” at “presyon ng iniksyon” are determined by the plastic. Some engineering plastics require higher injection pressure and appropriate screw compression ratio design to have better molding effects. Samakatuwid, in order to make the finished product shot better, the needs of injection pressure and compression ratio should also be considered when selecting the screw. .
Karaniwang nagsasalita, a screw with a smaller diameter can provide a higher injection pressure.
7. Shoot fast: and confirm the “shooting speed”.
Some products require high injection rate and rapid injection to form stable molding, such as ultra-thin products. Sa ganitong sitwasyon, it may be necessary to confirm whether the injection rate and rate of injection of the machine are sufficient, and whether it needs to be equipped with pressure accumulators, closed-loop control and other devices. Karaniwang nagsasalita, under the same conditions, the screw that can provide a higher injection pressure usually has a lower shot speed, sa salungat, the screw that can provide a lower shot pressure usually has a higher shot speed. Samakatuwid, kapag pumipili ng screw diameter, ang iniksyon dami, iniksyon presyon at iniksyon rate (iniksyon bilis) kailangang cross-itinuturing at napili.
Sa karagdagan, isang multi-loop disenyo ay maaari ring gamitin upang paikliin ang oras ng paghuhulma na may synchronized compound action.

Kung mayroon kang anumang mga katanungan sa iniksyon paghuhulma ,mangyaring huwag mag-atubiling magtanong Lumilipad koponan,bibigyan namin kayo ng pinakamahusay na paglilingkod!