How to deal with the problem of fusion line?

Reason analysis: From the perspective of plastics, the melting line is essentially caused by the incomplete melting of two plastic flow fronts.

Solution: To eliminate or reduce the melting line, plastics must have low viscosity, high temperature, sufficient pressure and enough time to melt completely. Usually, in the case of good exhaust, accelerating the filling and feeding speed and increasing the pressure as soon as possible after the combination of two plastic flow fronts will help to solve the melting line problem.


评论

发表评论

此博客中的热门博文

Detailed Explanation of Material Characteristics of PTFE Plate

Polytetrafluoroethylene sheet is made of 100% pure polytetrafluoroethylene by moulding, turning, cutting and other processes. Among the known plastics, it has the best chemical corrosion resistance, no aging, electrical insulation, and very low friction coefficient. It can be used at - 180 ~ + 260 degrees without load. Characteristic, high temperature resistance - working temperature up to 250 C. Polytetrafluoroethylene ( PTFE) sheet has good mechanical toughness and low temperature resistance, and can maintain 5% elongation even when the temperature drops to - 196 (?) Polytetrafluoroethylene (PTFE) sheets are corrosion resistant - inert to most chemicals and solvents, strong acid and alkali, water and various organic solvents. Polytetrafluoroethylene (PTFE) boards are climate-resistant and have the best aging life of plastics. High lubrication - the lowest coefficient of friction in solid materials. Non-adherence - is the smallest surface tension in solid materials. It do
阅读全文

Factors that are more susceptible to influence in the production of plastic products

Fillers, also known as fillers and fillers, are solid substances added to the matrix of polymer materials to reduce costs and/or improve some properties of products. The main factors to be considered when choosing fillers are as follows: 1. Low Price The price of filler has a great influence on the cost of  plastics . The proportion of polyvinyl chloride plastics with fillers is 2-3 times that without fillers. Therefore, the proportion of polyvinyl chloride plastics with fillers increases rapidly with the increase of the amount of fillers. Therefore, the cost based on weight is not as accurate as that based on volume. In application, the volume cost must be considered. The small proportion of filler is more advantageous to the volume cost. 2. Oil Absorption That is, the ability of fillers to absorb plasticizers. It depends on the fineness of filler and the variety of filler and plasticizer. The cost of plastics increases with the increase of oil absorption. 3. Electrical Pe
阅读全文

Analysis of Common Defects in Plastic Products-Size Change

Basic Reasons: From the perspective of plastics, the reasons for the size change are as follows: The change of pressure distribution in U-shaped cavity will cause the change of size. For crystalline plastics, the change of crystallinity due to the change of cooling rate will cause the change of size. After-treatment of U products, changes in ambient temperature and humidity can also cause size changes. Next, the change of pressure distribution in the cavity and the size change are analyzed and discussed. The causes of defects will vary with the size changes. First, defect phenomenon: the overall product size is too small. Cause analysis: the plastic pressure in the cavity is too low. Solution: Increase the feeding pressure to meet the cavity pressure required by qualified products. 2. Defects: Overall product size is too large Cause analysis: the plastic pressure in the cavity is too high. Solution: Reduce the feeding pressure to achieve the cavity pressure require
阅读全文