What is Plastic Machine Screw: (Mạ crom Trục Vít)
The plastic machine screw is a helical screw that compresses, melts and exerts the pressure to push the plastic
plastic into the mold.
There are many types of screws on the market. Each type has its own function.
Depending on the design of the manufacturer to create the best performance for plastic injection machines.
Plastic Machine Screw Structure:
Screws of plastic machines often use S45C, 40X steel, alloy steel.
After the turning process, the shaping milling is often heat treated to achieve wear-resistant hardness.
Here, steel grades and heat treatment processes are crucial to the life of the screw.
After the heat treatment is completed, the screw is Rounded on a dedicated grinder to return to the standard tolerances.
In order for the screw to work properly, and prolong the life it is often covered with a chrome plating layer.
The HARD CROM PLATED layer element for screw is considered to increase the life of the screw by 5-8 times compared to the absence of a coating.
The Role of Chromium Plating For Plastic Machine Screw:
Anti-stick plastic on the teeth.
High abrasion resistance for crowns and barrel.
Helps plastic escape faster thanks to standard gloss after polishing processing.
Withstand high temperatures for a long time.
Screws operate in environments subject to high abrasion friction as well as high temperatures. Intensity of continuous work. Therefore, Chromium screw coating is an indispensable process in the manufacture of plastic machine screws.
Similar to conventional HARD CROM PLATING layers, the Hard Hard Chrome Plating also follows the basic processes of Chromium Plating, but the main component and the key decision is the even chrome coating on the screw surface. how to effectively, and improve the difficulties with, the conventional chrome plating.
Process of Hard Chrome Plating Screw Plastic Machine
At our company, with the new chromium coating method, it helps uniformly hard hard chrome coating from the top of the teeth to the hidden corners, preventing the screw from local stresses peeling off the chrome plated layer, as well as the calculated product. Very high stability.
Chromium Coating Thickness for plastic machine screw:
Chromium Plating Thickness determines the screw surface hardness, Helps extend the life of Screw up to 5 times compared to other methods.
For new Manufacturing Screws, we usually coat the chrome layer with a thickness of 100 ~ 150 um.
Chromium Hardness For Plastic Machine Screw:
With thickness from 100 ~ 150 micron Screw surface hardness is improved from 65 – 68 HRC.
This hardness helps the screw improve abrasion and corrosion.
In order to ensure long-lasting screw, we often use surface heat treatment method for screw, Screw Heat Treatment method helps improve hardness by about 3 ~ 5 mm, Still ensures the Flexibility of the Shaft Screw during operation does not crack.
Plastic machine screw surface gloss:
The surface of the plastic machine’s screw surface determines the plastic drainage and hygiene factor when removing the screw, or converting the processed plastic.
The screw gloss is about Ra 0.2 ~ 0.05 um.
After Hard Chrome Plating, Polished Screw reaches luster Ra <0.2 um.
For special resins that contain glass fiber content, the screw may need to be polished to a Ra <0.05 um gloss.
Polished Screws
Plastic Machine Screw Repair:
At our company provides plastic machine screw repair services.
During use, the plastic machine screw inevitably gets worn, leading to inefficient operation. As the effect of plastic extrusion is poor, uneven, or less material.
Methods of fixing plastic screw machines:
For repaired screw types, it is necessary to understand the screw specifications:
Specifications such as Diameter, Screw and Cylinder Bore diameter must be suitable for the best performance in the manufacturing process.
Because the operation process leads to abrasion of both Screw and Cylinder barrel, when carrying out Screw recovery, we have to combine Plastic Machine Cylinder treatment to create the best performance for the machine.
Conventional The most commonly used method for Plastic Machine screw repair and repair is the Hard Chrome Plating Method.
Abrasive conventional screw types may miss from 0.2 ~ 1 mm. Chromium Coating will help restore the original diameter of the Screw.
This method is both cheap and highly effective, Handling at room temperature so it does not cause deformation of steel materials.
Plastic Machine Screw Repair Process.
Remove Chromium Plating
Screw of the plastic machine, after being removed from the cylinder barrel, is cleaned and performed Hard Chrome Plating Release.
Welding Screw Fixes
After peeling off the hard chrome plating, the screw is argon-welded.To overcome surface defects such as Pitting Embryos, Corrosion, Heavy Scratches.
Repairing Screw Corrosion
Grinding Round Screw
Next The screw is mounted on a circular grinder to sharpen the top surface, eliminate minor imperfections, and return to the same size with a tolerance of Grinding + – 0.02mm
