Injection molding systems require the use of a gating s […]
Injection molding systems require the use of a gating system. What are the requirements for the gating system?
When the injection mold is used, its polishing has two purposes. One is to increase the smoothness of the mold, so that the surface of the product can be smooth, beautiful and beautiful. The other is that the mold can be easily released, so that the plastic is not stuck. The mold can't be removed.
The following matters should be noted in the injection mold polishing:
(1) When a new cavity begins to be machined, the surface of the workpiece should be inspected first, and the surface should be cleaned with kerosene so that the surface of the oilstone does not stick to dirt and the function of cutting is lost.
(2) When researching rough lines, it should be carried out in the order of difficulty and easyness. Especially some dead corners that are difficult to study, the deep bottom must be studied first.
(3) Some workpieces may have multiple pieces assembled together to grind light. It is necessary to separately study the rough or fire pattern of a single workpiece, and then all the workpieces are ground and smoothed.
(4) For workpieces with large planes or side planes, use oil stone to grind coarse lines and then use straight steel sheets for light transmission inspection to check whether there are any uneven or inverted buckles. It is difficult to release the part or the piece is strained.
(5) In order to prevent the mold workpiece from being cracked or has some bonding surfaces to be protected, it can be pasted with a saw blade or sanded on the edge to obtain an ideal protective effect.
(6) The plane of the grinding mold is pulled back and forth, and the handle of the oil stone is pulled as far as possible, not exceeding 25°; because the inclination is too large, the force is rushed from the top to the bottom, which easily leads to the development of many rough lines on the workpiece.
(7) If the plane of the workpiece is polished with copper or bamboo pressed sandpaper, the sandpaper should not be larger than the tool area, otherwise it will be researched where it should not be studied.
(8) The shape of the tool to be ground should be close to the surface shape of the mold to ensure that the workpiece is not deformed by grinding.
When designing the casting system, the injection molding system firstly realizes the position of the gate of the hall. The selection of the gate position is directly related to the quality of the product and the smooth progress of the injection process. The selection of the gate position should follow some principles.
1 The position of the gate should be selected on the parting surface as much as possible to facilitate the cleaning of the gate during the processing and use of the mold;
2 The distance between the gate position and each part of the cavity should be as uniform as possible, and the process is shorter;
3 The position of the gate should ensure that the plastic flows into the cavity, and the cavity is wide and thick, so that the plastic can flow smoothly;
4 The gate position should be opened at a thicker section of the plastic part;
5 to avoid the plastic straight into the cavity wall, core or insert when flowing down the cavity, so that the plastic can flow into all parts of the cavity as soon as possible, and avoid deformation of the core or insert;
6 Try to avoid causing weld lines in the product, or make the weld marks appear in the unimportant parts of the product;
7 The position of the gate and the direction of its plastic inflow should allow the plastic to flow uniformly in the direction parallel to the cavity when flowing into the cavity, and facilitate the discharge of gas in the cavity;
8 The gate should be placed on the product to be easily removed, while not affecting the appearance of the product as much as possible.