What is the injection molding process?

The first is the clamping process: the clamping cylinder.

The pressure oil in the mold pushes the clamping mechanism to move, and the moving plate moves to close the mold.

The second step is the injection device: after the mold is locked with the clamping force during the injection process, the injection device enters the working condition to make the nozzle and the mold fit.

The third step is the pressure holding process: in the process of filling the mold cavity until the melt is filled, the screw is required to maintain a certain pressure on the melt to prevent the melt in the mold from backflowing.

The fourth step is cooling and pre-molding process: once the gate is sealed, the pressure holding process is canceled, and the product is naturally cooled and shaped in the mold; At the same time, Dekumar injection molding machines.

The pre-plastic oil motor is driven to rotate the screw and convey the granular plastic from the hopper forward for plasticization.

The fifth step is the process of rejecting the injection device, opening the mold and ejecting the plastic products: after the preplastic metering and anti-delay process, in order to prevent the nozzle from forming cold materials due to long-term contact with the cold mold, etc., it is usually necessary to withdraw the nozzle from the mold, that is, to enter the injection device to return to the working condition.

In the injection molding process, the screw injection machine is used as an example, the mold is first clamped and locked, and the mold is quickly closed at low pressure through the clamping mechanism, and when the moving plate and the fixed plate are about to approach, the moving plate advances at low pressure and low speed.

When it is confirmed that there are no foreign objects in the mold, the mold is closed and locked with high pressure. Then there is the forward movement of the injection system and the injection and pressure holding. After the mold is locked, the injection system moves forward to make the nozzle and the mold fit, and the screw moves forward quickly under the action of the piston of the injection cylinder, and the melt at the front end of the barrel is injected into the mold cavity at high pressure and high speed.

Injection molding: refers to a model with a certain shape, through the pressure of the molten state of the colloid into the mold cavity and molding, the process principle is: the solid plastic is melted according to a certain melting point, through the pressure of the injection machine, with a certain speed into the mold, the mold through the cooling of the plastic to obtain the same product as the design mold cavity.

Material temperatureThe processing temperature of the plastic is controlled by the barrel of the injection machine. The correct choice of barrel temperature is related to the plasticizing quality of the plastic, and the principle is to ensure smooth injection molding without causing local degradation of the plastic. In general, the maximum temperature at the end of the barrel should be higher than the flow temperature (or melting temperature) of the plastic, but lower than the decomposition temperature of the plastic.

In addition to strictly controlling the maximum temperature of the barrel of the injection machine in production, the residence time of the plastic melt in the barrel should also be controlled. When determining the barrel temperature, the structural characteristics of the product and the mold should also be considered. When forming thin-walled or complex-shaped products, the flow resistance is high, and increasing the barrel temperature helps to improve the fluidity of the melt.

The maximum temperature of the nozzle is usually controlled to be slightly lower than the maximum temperature of the barrel to prevent the melt from drawing at the nozzle mouth.

The dried plastic particles or powder are added to the barrel of the plastic injection molding machine from the hopper, melted and plasticized by heating, and then the molten plastic is injected into the mold with a lower temperature under high pressure through the plunger (or screw), and the mold is opened after cooling and shaping to obtain the corresponding products.

Injection molding is a continuous process, which can actually be divided into several steps, such as raw material drying, feeding, plastic melting, injection, pressure holding, part cooling, part demoulding, and part trimming.

Hello dear, glad to answer for you. The production process of injection molding products is the injection molding process of plastic parts, which mainly includes four stages: filling, pressure holding, cooling, and demoulding. Filling is the first step in the entire injection molding cycle, from the time the mold is closed and the injection molding starts until the mold cavity is filled to about 95%.

Theoretically, the shorter the filling time, the higher the molding efficiency, but in practice, the molding time or injection speed is limited by many conditions. The role of the packing phase is to continuously apply pressure to compact the melt and increase the density (densification) of the plastic to compensate for the shrinkage behavior of the plastic. During the packing process, the back pressure is high because the mold cavity is already filled with plastic.

In the process of packing and compaction, the screw of the injection molding machine can only move forward slightly, and the flow speed of the plastic is relatively slow, and the flow at this time is called the packing flow. In injection molding molds, the design of the cooling system is very important. This is because the molded plastic products can only be cooled and solidified to a certain rigidity, and the deformation of the plastic products due to external force can be avoided after demolding.

Since the cooling time accounts for about 70% to 80% of the entire molding cycle, a well-designed cooling system can significantly reduce the molding time, increase injection molding productivity, and reduce costs. A poorly designed cooling system can lengthen the molding time and increase the cost. Uneven cooling will further cause warping and deformation of plastic products. Demolding is the final link in an injection molding cycle.

Although the product has been cold-set molding, the demoulding still has a very important impact on the quality of the product, and the improper demoulding method may lead to uneven force on the product during demoulding, and defects such as product deformation caused by ejection.

Hello, dear, now for you to answer 1, blister: Vacuum forming is called blistering, is a plastic processing technology, the main principle is to heat the flat plastic hard sheet to soften, use vacuum adsorption on the surface of the mold, cooling and molding. It is mainly divided into two categories: thick film blister and thin sheet blister.

It is widely used in automotive accessories, lighting, advertising, decoration, large mechanical shells, displays, airspace, major appliances, sanitary ware and other industries. 2. Injection molding: that is, thermoplastic injection molding, this method is to melt the plastic material and then inject it into the film cavity.

Once the molten plastic enters the mold, it is cooled and molded into a certain shape according to the mold cavity. Common products mainly include: computer case shells, connectors, mobile phone shells, keyboards, mice, audio, etc.

3. Blow molding: also known as hollow blow molding, a rapidly developing plastic processing method. The tubular plastic parison obtained by extrusion or injection molding of thermoplastic resin is placed in the split mold while it is hot (or heated to a softened state), and compressed air is introduced into the parison immediately after the mold is closed, so that the plastic parison is blown up and clings to the wall in the mold, and various hollow products are obtained by cooling and demoulding.

Blow molding is used in the processing of bottles, barrels, cans, boxes, and all containers for packaging food, beverages, cosmetics, medicines, and daily necessities. 4. Extrusion: Extrusion molding is also known as extrusion in plastic processing, and extrusion in rubber processing.

It refers to a processing method in which the material is made into various cross-sectional products or semi-finished products through the action between the extruder barrel and the screw, while being thermoplasticized, and being pushed forward by the screw rod through the machine head.