Operating principle of China’s over-molding machine

The operation of China’s over-molding supplier comes from injection molding technology. The heated liquid polymer raw material in the mini injection molding machine is injected under high pressure into injection molds. Moreover, it makes it possible to obtain various small-sized products of any configuration, with walls of various thicknesses.

Molding stages of mini injection molding machines

Products are molded in special molds, the quality of which determines the accuracy of the specified parameters and geometric dimensions.

Moreover, thermoplastic molding in mini injection molding machines carries out in several stages:

1. The prepared polymer raw material is loaded into the receiving compartment of the injection molding machine, from where it enters the screw zone, where it is heated and melted.
2. Simultaneously, the plates of the molds connect, forming a cavity inside for receiving the molten mass.
3. The screw-piston, moving forward, and then supply the polymer mass melted in the screw zone.
4. Through the mouthpiece of the plasticizing module, under high pressure, the molten mass is injected into a closed mold. At the same time, the non-return valve, performing the function of dosing the polymeric material, prevents the release of the melt into the pre-mouthpiece zone. Moreover, the air from the injection molding machine will be forced out through the existing air valves and removed to the ventilation system.
5. Molded products are kept under the influence of high pressure for the time specified by the program, and then the molds cool.
6. As the molds cool down, the pressure gradually decreases.
7. The cooled molds open, and the finished products are ejected by an automatic ejector unit.
8. The auger returns to its original position.
9. The molds connect to pour the next portion of the plastic melt.

Cycle thermoplastic molding

Moreover, it can be from two to three seconds, up to ten minutes, depending on the wall thickness. The configuration of the products and the polymer raw materials used.

The operation of the injection molding machine for micro-molding

Automated control with the help of an integrated controller makes it possible to manage with a small staff of service specialists. However, which can significantly save on overhead costs when servicing the operation of the injection molding machine for micro-molding.

Moreover, security and control systems in case of emergencies will turn off the machines automatically.

Overview of injection molding machine’s model comparison

According to the principle of operation and the location of the main components, all models of standard mini injection molding machines in the horizontal version of the SS series are similar to each other. They have a vertically located mold parting plane with the horizontal injection of molten material.

Moreover, screw diameters, overall dimensions, weight, engine and heater power, clamping force, injection force, and volume of mini injection molding machines are different.

However, the main classification indicators are the efforts required to lock the mold, providing a closure node. 

A wide range of models of China’s injection molding machines of the SS series will allow you to choose machines for the manufacture of polymer products with the required performance for various purposes.

Steps of the injection molding process

Injection molding is a rather complex physical and chemical process, which consists of the melting of thermoplastic materials, followed by the transfer of the mass into the mold cavity, which is cooling then, and molding the required geometry.

Let’s consider this process in more detail.

The minimum set for the production of plastic products includes the purchase of the material and the manufacture of a mold for molding a specific product.

Moreover, after installing the injection molding machine, connecting it to the electrical network, supplying water for cooling the hydraulics and mold channels. The start-up and debugging of the molding process itself begin.

You need to heat the material in the screw pair

Modern injection molding machines have protection against the so-called cold start. Moreover, electronics simply will not let you turn the screw without reaching the temperature of the melted mass to the desired values. Thus, the screw will only rotate if the mass melts and there is a molten state.

The principle of operation of the injection molding machine

Injection molding machine – specialized equipment for injection molding of thermoplastics. Now, this is the most used way to create parts from polymer materials for several reasons:

• High manufacturability;
• Excellent performance;
• Possibility of automation;
• No further machining is required.

Moreover, thermoplastics, which are necessary for molding, have an extensive list of physical and chemical indicators. 

The manufacturing process of Injection molding

China’s over-molding suppliers‘ consumables are thermoplastic polymer particles. However, the manufacturing process takes place in several stages:

1. Drying plastic material;
2. Placing the plastic material in the receiving compartment of the machine;
3. Pouring the plastic material into the screw of the equipment and melted;
4. Then the plastic material enters the mold with the help of a piston;
5. Passing the sprue cavities, filling the mold;
6. The plastic solidifies in a chilled form;
7. The mold opens, with the molded product finished.

Injection molding machine’s design

The main parts for the operation of the machine are the plasticizing unit and the clamping unit, which move with the help of hydraulic actuators and an electric motor. Moreover, the injecting unit manages all stages of electric and hydraulic drives and also sets the cycle settings.

However, to heat up the material, the operator sets the temperature values ​​for each zone, which can be from 3 or more, depending on the design of the injection molding machine and its size. Typically, the required temperature values ​​for the zone specified by the manufacturer of thermoplastic materials.

The installation of the injection mold

While the plastic material is heated in the screw pair, you can proceed directly with the installation of the mold. To do this, the plates of the Injection molding machine’s clamping units are bred; the mold is placed in the cavity between them, centered on the fixed plate by introducing a centering ring into the plate cavity. 

Moreover, the operator gradually closes the plates until the movable plate comes into contact with the end face of the mold. After these operations, the mold fixes to the plates by means of bolts or clamping systems. However, they are usually supplied with injection mold.

In recent years, we have noticed an unprecedented increase in the interest of our customers in the purchase of China plastic over-molding machines. They are of various designs with a small clamping force from 15 to 100 tons. They carry an injection volume of up to 250 cubic centimeters.

This factor comes from the demand of the plastic injection market for the transition from the production of collapsible products. These products have a basis in the form of embedded elements poured with plastic compounds.

Most demanding plastic over-molding machine

The most demanded project today is the molding of an electric plug. This product comes from hundreds of enterprises in Europe, despite the strong competition from Chinese manufacturers. But with the growth of the foreign exchange rate, China’s plastic over-molding machine becomes more cost-effective and secure.

So, in the line of vertical injection molding machines, we have several types of thermoplastic machines. They differ in the closure unit. These distinctions come for the convenience of the operator in inserting inserts and removing finished products. Similarly, they increase product productivity.

Vertical plastic over-molding machine: a computer control system

The vertical injection molding machines come with a computer control system. Similarly, they come with an LCD monitor. There is a graphical display of all the actions and parameters of the injection molding machine. All settings for the parameters of the injection machine are important.

Many of our customers purchase China plastic over-molding machines to replace syringe machines manufactured in the USA.

Increasing quality of the resulting products

Subsequently, they note such positive qualities as ease of control, productivity growth, an increase in the quality of the resulting products. It is due to a more powerful injection, as well as mixing the material with a screw. This process allows obtaining the uniformity of the melted mass and its temperature balance.

China plastic over-molding machine: moving parts controlled by potentiometric rulers

This ensures high positioning accuracy of the injection unit, closing, and pusher operation. The control panel of the injection molding machine comes with a memory of molding parameters for 120 sets of molds.

Moreover, it makes changing the tooling easy and fast. It is enough to change the mold and select the program corresponding to it. The machine itself will set all the molding parameters.

China plastic over-molding comes both in a standard version and with the possibility of equipping with a servomotor. It saves electrical energy during product cooling and the manual labor of the operator for laying embedded elements.

A servo drive is immediately obvious

Savings from the installation of a servo drive are immediately obvious. The time of the operator’s work and cooling of the product takes up a large part of the molding cycle.

Now I would like to compare the vertical injection molding machines offered by us in terms of the design of the clamping unit. All machines supplied are hydraulically driven, which means that the closing occurs due to the movement of the piston, which fills with hydraulic oil.

The difference exists in the execution of the bottom plate. It is of two types, movable and fixed. Mobile plates are equipped with models with a sliding, shuttle, double shuttle, and rotary table.

China plastic over-molding machine designed to increase productivity

The sliding table is specially designed for the convenience of working with embedded elements and overall products. It is common when it becomes problematic to insert mortgages due to the limited opening of the plates of the clamping unit. The lower plate, when opened, leaves towards the operator, where he easily carries out his work.

Shuttle table injection molding machines are designed to increase productivity as the bottom plate has two mold halves that alternately mate with the top plate. The essence of productivity growth lies in the parallel work of the operator and plastic over-molding process.

Vertical injection molding machines with a double shuttle table

Vertical injection molding machines with a double shuttle table distinguish by the fact that the lower halves of the mold move at a right angle, allowing operators not to move during operation, as the tables move out to the left and right of it.

Finally, the rotary table vertical injection molding machines characterize by the ability to install from one to four lower half-molds. It is also possible to perform TPA for two-component or two-color molding.

The best option to purchase China plastic over-molding machine

If you have a need to purchase a vertical injection molding machine, welcome to contact our specialists. They will select the best option for you, as well as calculate the cost of molds and all the necessary equipment.

The constancy of the temperature of the mold cavity guarantees the exact repeatability of the product, maintaining the specified geometric dimensions. Among other things, by setting the foundry cooling cycle, you can be sure that it will be constant with a given temperature, which also guarantees the constancy of the quality of the molded products.

Prefer the device with a thermostat for a mold

We suggest paying attention to such a device as a thermostat for a mold. This China plastic over-molding machine connects to the cooling channels of the mold, as well as to refrigeration equipment or running water.

The meaning of the work is to maintain the temperature of the coolant. It can be water or special heat-resistant liquids that are common at higher temperatures of the equipment.

The thermostat is equipped with heating elements

The essence of the work lies in the fact that the thermostat is equipped with heating elements that heat the coolant, as well as a pump that circulates the liquid in the channels of the China plastic over-molding machine.

Thus, there is a maintenance of a constant temperature of the coolant, and hence the cavity of the mold for plastic parts.

Thermostats are of water and oil type

The former is common for temperatures up to 100℃, the latter for a significantly higher liquid temperature. Also, thermostats are single and multi-circuit, which allows you to stabilize the temperature in several independent circuits.

To select an injection molding machine, you need to decide on the required power, because there are devices with heating power from 2 kW to infinity. It all depends on the weight of the mold and the mold cooling system. The mass of the part has a greater effect on the amount of cooling required and is usually not included in the calculation.

In addition, if you have any questions about temperature stabilization when molding plastic products, please contact our specialists. They will choose the most suitable type of equipment for you.

Injection mold making equipment

Aluminum products are in demand in various industries, including in construction, mechanical engineering, aircraft construction, injection mold making, etc.

Moreover, specially designed equipment for Injection mold making simplifies the process of producing parts with a high-quality smooth surface, with accurate linear and geometric parameters.

Features of aluminum in injection molding

Aluminum is a soft and lightweight material with a low melting point. Therefore, the technical properties of aluminum make it possible to produce cast products even in artisanal conditions and small workshops.

In addition, it is common in almost all industries, due to its low cost and excellent performance:

• Firstly, low melting point and good fluidity, allowing the manufacture of products of complex configurations;
• Secondly, low density and lightweight;
• Thirdly, and most importantly, high corrosion resistance;
• Finally, only Slight shrinkage of the molded parts;

Aluminum components perfectly process on injection mold making in China, hand and power tools. Therefore, by adding various modifiers and additives, it is possible to achieve an increase in mechanical strength, resistance to salts and chemicals, and heat resistance.

Injection mold making – process features

When manufacturing products in an injection molding machine, aluminum scrap metal heats to 600 ° C and above. The melt moves into the molding chamber. In addition, with the help of a powerful piston under a certain high pressure, it injects into the split molds.

The main advantages of the molding in machines:

• Good performance;
• High process speed;
• Low energy consumption;
• Low cost of production;
• Moreover, automation of injection molding reduces the complexity of the process and cuts down human labor;
• Accurate dosage eliminates the loss of aluminum raw materials;
• Therefore, with the help of injection molding, it is possible to create thin-walled products, with a minimum thickness of one millimeter.

Casting methods in injection mold making in China

Aluminum continues to be an affordable metal, actively common for the manufacture of a wide variety of parts and structures.
In addition, the choice of technology and casting methods depends on the quality requirements, the required characteristics, and the linear dimensions of future products.

The most popular ways:

1. Injection mold making in China– common to produce blanks of good quality, with precise geometric shapes.
2. The material comes in injection molding machines using proven technology:
3. Raw material heats to a liquid state under the influence of high temperature, over 600°C;
4. Hot metal moves to the pressing module with the help of a screw;
5. A piston moving under pressure up to 700 Mpa injects the melt into the mold;
6. Later, after the cooling is completed, the finished part removes outside.
7. This technology allows you to create products of various designs with minimally thin smooth walls.

Molding in a machine is an automated process

Molten metal in injection mold making in China is poured into the one-piece formwork from above. Cooled finished products are simply ejected by the mold. In addition, split molds come with a vertical, horizontal, or curved split plane. 

Importance of pressure in injection molding in China

Injection molding using pressure allows you to produce thin-walled products of various configurations, weighing from a few grams. In addition, parts may have various cuts, grooves, recesses, holes, or threads.

Main advantages of injection mold making

Moreover, this technology has many advantages, among which are:

• High-performance equipment;
• Accuracy of geometric and linear parameters;
• The smooth surface of finished products does not require further processing.

Therefore, injection molding is common to create batches of products for medicine, the pharmaceutical, food industry, machine and aircraft industries.

Professional Equipment for injection molding in China

High-precision Injection mold making is essential for pipes, bushings, jewelry, and many other miscellaneous parts.

 

Using injection molds in China, it is convenient to create parts of various shapes with walls as thin as 0.5 mm. Therefore, with this technology, even smooth surfaces of cast parts obtain. Moreover, the molded parts do not need any mechanical modification.

Several stages of the molding process

In addition, operations for the production of Injection molds carry out in several stages:

1. The raw material melt at the proper temperature in the hooper.
2. The melted material is fed into the plunger of the injection molding machine.
3. With the help of a screw, the molten material moves to the molding department.
4. The hydraulic piston in injection molds injects the molten material through the nozzles into the steel split mold for slow cooling.
5. Eject the cooled molded parts – the mold opens and the products are taken out.

In conclusion, the production cycle for creating molded parts in special Injection molding machines takes from a few seconds to a few minutes. Moreover, the time spent depends on the dimensions of the workpiece.