Surface treatment and service life of injection molding machine screw
Published:
2022-10-13 11:51
We have emphasized many times that the screw barrel is the most critical and soul part of the injection molding machine. During the injection molding process, plastic raw materials enter the barrel of the injection molding machine from the tail. The screw rotates in the barrel, extrudes and pushes the plastic particles and their fillers, blends and plasticizes in the advance, and injects the screw head into the mold cavity. At this time, the barrel and screw bear certain high temperature and high pressure of different plastics, and the working temperature of the screw of the injection molding machine is also different.
We have emphasized many times that the screw barrel is the most critical and soul part of the injection molding machine. During the injection molding process, plastic raw materials enter the barrel of the injection molding machine from the tail. The screw rotates in the barrel, extrudes and pushes the plastic particles and their fillers, blends and plasticizes in the advance, and injects the screw head into the mold cavity. At this time, the barrel and screw bear certain high temperature and high pressure of different plastics, and the working temperature of the screw of the injection molding machine is also different.
Screw barrel is often scrapped due to excessive clearance caused by wear and can not be squeezed or injected normally. The wear increases the clearance between the cylinders of the screw edging machine, which leads to the reduction of the melting rate and the pumping capacity, resulting in uneven material temperature and pressure fluctuations, resulting in a decline in product quality, a reduction in productivity and an increase in energy consumption. Compared with the barrel, the screw is more prone to damage and failure.
Other
10/13
2022
Boronizing treatment of steel screw barrel surface
Screw and barrel are mostly scrapped due to large gap caused by wear, which can not be extruded and injected normally. Few of them fail due to insufficient strength. Especially, in addition to strength, more consideration should be given to structural commonweal and thermal inertia in the design of barrel, and the wall thickness determined by the latter two factors should be far greater than the calculated value of strength conditions
View detail10/13
2022
Extruder Screw Design and Repair Process
The extrusion system consists of screw and barrel, which is the "heart" of extrusion work. The screw completes the continuous conveying, plasticizing, homogenizing, constant pressure and quantitative extrusion of plastics in the barrel. The types of screws are: constant pitch gradual change screw, constant pitch depth abrupt change screw, variable depth variable pitch screw, etc. The structure of constant pitch progressive screw is studied as an example. Its main features: the thread pitch of the screw thread is equal, while the depth of the thread groove remains unchanged in the feeding section and homogenizing section, while the depth of the thread groove in the plasticizing section gradually becomes shallow from the depth, which is suitable for extrusion plasticization of various plastics. The progressive screw divides the working length of the screw into three basic functional segments,
View detail10/13
2022
How to judge the output of extruder screw?
The output is a main index to evaluate the performance of extruder screw. However, it is not significant to only emphasize the percentage increase in the output of the improved screw compared with the original screw, because the benchmark for comparison is not clear. From the theory of fluid dynamics, we know that the output will be greatly improved if the worn screw is replaced by the screw with smaller screw clearance. In order to accurately reflect the performance of the screw, the following four aspects can be compared.
View detail10/13
2022
Share standards for extruder screw performance
Extrusion process is a complex process, which involves many factors. Facts show that it is one-sided to evaluate the performance of extruder screw only according to the productivity. As we all know, if the colleague with high output has high capacity consumption, the screw is not desirable. For another example, if the extrudate has a high temperature rise at the same time of high output, the cooling burden of the main and auxiliary engines will increase. In fact, such screws cannot be used at high speed, and their performance is not much better than that of ordinary screws at low speed.
View detailNo. 9, Jixiang Road, Xihou Industrial Zone, Jintang Town, Dinghai District, Zhoushan City, Zhejiang Province
Scan WeChat