Plastic Injection Molding
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Plastic Injection Molding

Injecting plastic into a mold is a process used to make large batches of plastic parts. This procedure involves creating a mold by melting the plastic into it. TEAM MFG is a leading provider of plastic injection molding services in various industries such as food processing, medical, and construction. TEAM MFG is a leading plastic injection molding company in China that has been in the industry since 2003. We serve customers all around the world and are committed to providing the highest quality products and services. Our customers range from first-time inventors all the way up to Fortune 500 companies. We are an ISO 9001:2008 certified injection molding company.
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Plastic Injection Molding Services


Injecting plastic into a mold is a process used to make large batches of plastic parts. This procedure involves creating a mold by melting the plastic into it. TEAM MFG is a leading provider of plastic injection molding services in various industries such as food processing, medical, and construction. TEAM MFG is a leading plastic injection molding company in China that has been in the industry since 2003. We serve customers all around the world and are committed to providing the highest quality products and services. Our customers range from first-time inventors all the way up to Fortune 500 companies. We are an ISO 9001:2008 certified injection molding company.


Our Plastic Injection Molding Services

● Production Molds

● Export Molds

● Family Molds

● Insert Molds

● Overmolding

● Compression Molding

● Value Added Services

● Plastic Injection Molding

● Thermoplastic Injection Molding

We use an offshore injection molding facility to provide our customers with lower pricing than our domestic competitors. Quality is our top priority, and we use our quality systems to ensure that the parts we produce are of the highest possible standards. Our quick turnaround time allows our customers to get their orders done within three days. Our online quote system also provides instant quotes for various plastic injection molding services.


Plastic Injection Molding Analysis Services

● Injection Molding Basics

● Advanced Technology Injection Molding

● Calculate Plastic Mold Shrinkage

● Calculate Cooling System In Injection Molding

● Custom Injection Molding Thermoplastic

● Clamp Tonnage Injection Molding

● Gas Assist Injection Molding

● CAD Design Service

Since 2016, TEAM MFG has been a leading manufacturer of plastic injection molded parts for various industries such as medical, transportation, food & beverage, and more. We have successfully completed projects in Europe, South America, and the US. Since 2016, we have been working on custom plastic injection projects for various industries. Some of these include food & beverage, medical, and various other applications.


The custom molding process at TEAM MFG begins with our instant online quote system. We provide low-cost plastic injection molds and CNC machined plastic prototypes. TEAM MFG provides inexpensive custom molds and injection mold plastics, and typically charges 30%–50% less than other plastic fabricators.  We offer various types of injection molds depending on the type of parts that you require and the expected production cycles. Some of these are in-house injection plastic molds that run in our factory, while the other ones are exported.


Steel is commonly used for making plastic injection molded parts due to its durability and the ability to produce complex plastic parts. Other steel types are also used for making plastic injection mold. P-20 is commonly used for making plastic injection molded parts, but other steel types are also used. From start to finish, we can help you get the job done right and fast. We can also help you get started with exporting plastic parts.


Plastic Injection Mold Manufacturing Process Flow

Injecting resin into a mold is a manufacturing process where heated resin is fed into a machine. The resin is then shot into the part to form it. The pellets are then compressed and injected into the machine's runner system. The resin then goes through a funnel-shaped hopper to get into the machine. It is then heated to a temperature of over 120 degrees Celsius and is compressed into a heated chamber.


As the plastic particles are slowly moved forward, they are forced through a nozzle that's designed to allow them to enter the mold cavity. The temperature of the resin remains at a set point. The injection molded part remains at a set temperature so the plastic can solidify almost as soon as the mold is filled. The part cools and hardens to the shape of the mold cavity. The ejector pins then push the part out of the mold and into a bin.


Select The Right Injection Molding Plastic

When it comes to injection molding plastics, there are a few options available in the industry:

● Crystalline Plastics

● Amorphous Plastics

● Imidized Plastics

● Polyethylene (PE)

● Polypropylene (PP)

● Acrylonitrile Butadiene Styrene (ABS)

● Polyoxymethylene (POM)

● Polystyrene (PS)

Deciding on the right plastic for your project is an important step in the process of injection molding. Aside from its properties, different resins also have their own characteristics. Performance, flexibility, and color are some of the factors that are often considered when choosing the right plastic for a project.


Plastic Injection Molds Making

Injection mold tooling is a part of the process that's used to mold components into their image. The cavity side of a part is typically the half that's designed to have the best surface area. The core side, which is the other half, is typically the part that gets ejected from this half.


Conventional machining is used for making injection molds, while CNC machines are used for complex parts. Due to the technological advances in the field of injection mold manufacturing, CNC machines have become the preferred method of making complex parts.


Electrode-Magnetic (EDM) is a process that involves a copper or graphite electrode being lowered into a mold, which is then submerged in paraffin oil. This method creates a mold's uneven surface, which can be difficult to machine. Due to its versatility, many companies in the industry now have in-house EDM machines. This process allows injection mold manufacturers to create designs that are difficult to machine due to their various features, such as ribs and square corners.


Compared to other manufacturing processes, such as 3D printing, injection molding tends to require a high up-front investment. Despite the high initial investment, injection molding usually costs less than other manufacturing processes. It is also a much faster and cheaper method to produce identical parts.


Molds can be made of various materials such as steel, aluminum, and copper alloy. The number of parts that are required for a given production cycle is also taken into account. Steel mold lifespans are usually longer than those made from aluminum or copper. This allows the machine to produce a wider variety of parts. Pre-hardened steel injection mold are usually used for lower volume parts.


Depending on the material's origin and economic conditions, aluminum can be made into various shapes and sizes. It's cheaper than steel molds. Copper can also be made into various shapes and sizes, especially in areas where high shear heat is generated.


Complex plastic parts can also be produced through injection molding. In simple cases, the two mold halves are ejected after the part is finished. A simple part can be produced through injection molding if it has no overlapping or undermining features. To accommodate various features such as undercuts, such as side-pull mechanisms, mold casings can be augmented with slides. These components are drawn into a cavity using a perpendicular direction. The pins are then inserted into the slides and force them to move backward once the part is ejected from the mold. The mold then closes.


Multiple-Cavity Molds (Family Molds)

In addition to a single part, a mold can also be made to produce multiple versions of the same part. This type of mold can be called a single impression mold or a multiple impression mold. Sometimes, high-volume mold designs can produce over 128 cavities. A multiple impression mold is commonly referred to as a family mold. This type of mold can produce multiple, similar-sized parts in the same material and quantity.


Overmolding

Overmolding is a process that's commonly used to produce multi-material parts. For instance, it can be used to make a grip for a tool or a game controller that's made out of a different material. A game controller or a power tool can be made to have different textures and materials incorporated into its body. In this process, a part is re-introduced into an injection machine, while a different material is injected into it to form a new layer. Some machines can also produce two-shot or multi-shot injection machines. For instance, a two-shot injection mold is used to mold a basic shape, while the second material is injected into the other open spaces.


Despite its numerous advantages, overmolding is not as simple as injection molding a single part. The process requires the use of compatible and chemically stable materials. Since the melt temperature of the substrate material is different from that of the overmolding resin, the parts produced through this process may get deformed.


Insert Molding

Metal, plastic, and ceramic pieces can be molded into multi-material parts that have additional features and functionality. Instead of having to install the parts after the process, insert molding allows the parts to be molded into the mold without having to be secured. Also, it allows the parts to withstand high temperatures and pressure. Since the insert pieces are molded during the time of production, they're more robust than those molded using post-molding techniques.


This type of mold is typically harder to work with than the injection process. Usually, companies that specialize in insert molding have more experience in the process. For low-volume production runs, an operator may place the insert parts into the mold. However, for high-volume production, an automated machine may be used.


Molding Cycle Time Analysis

The cycle begins after the mold closes and the resin is injected into it. It maintains a holding pressure to prevent material shrinkage. The next shot is directed at the front of the screw, which then turns and releases the resin. A formula can be used to determine the cycle time of injection molding. The time it takes to make a part using injection molding is calculated as:

Total time = 2M + T + C + E

Where:

(2M) = Twice the Mold Open/Close Time

(T) = Injection Time (S/F)

(C) = Cooling Time

(E) = Ejection Time (E)

(S) = Mold Size (in3)

(F) = Flow Rate (in3/min)

The times and locations of injection molded parts can vary depending on the size of the machine and the nature of the part.


Process Efficiency

Optimizing the injection molding process is essential because it affects cost, quality, and productivity. Some of various optimization checks include:


• Optimize the holding time by conducting gate seal or gate freeze studies

• Conduct a cooling time study to optimize the cooling time for an injection molded part

• Pressure drop studies determine if the machine has enough pressure to move the screw at the set rate

• Perform viscosity curves to determine injection speeds

• Vary the melt temperatures and holding pressures to optimize the process window


Mold Trial Analysis

When a new injection mold is being made, a trial procedure is carried out to get everything dialed in. The first step involves filling the mold with a small amount of weight and gradually increasing the holding pressure until it reaches a certain size. This step's goal is to determine the cycle time and determine the gate freeze off time to make the process more efficient. The holding pressure is increased until the gate freeze off occurs, which is a crucial step in the cycle time calculation. This step is also important because it affects the profitability of the production process. After the gate freeze off time has been determined, the holding pressure is decreased until the part is finished with its weight. The gate solidification process is also conducted to determine the cycle time and the profitability of the production process. The holding pressure is increased until the part weight is achieved and the sink marks are minimized. A set of guidelines is then produced to standardize the injection molding process.


Equipment for Plastic Injection Molding

Plastic injection machines are machines that are used to produce plastic parts. They operate by using a mechanical pump and a plastic valve to inject the resin into the mold.


The clamping force exerted by a plastic injection machine is rated by tonnage. Its force is calculated by taking the area of the molded part that's being molded and multiplying it by 2 to 8 tons. The more clamping force the machine uses, the more it will close the part. The area of the part that's being molded is then multiplied by the clamping force to get the total tonnage needed. Usually, 4 to 5 tons per inch is used for most projects. The more clamping force the machine uses, the more resin it will need to hold in the mold. It generally uses 4 to 5 tons per inch.


Electric injection machines are more energy-efficient and offer better repeatability. However, they are still 30% more costly than traditional presses. Though the cost of electric presses is 30% higher, greater demand for plastic injection-molded parts has largely closed the gap on cost.


Injection Molds: Aluminum vs. Steel

The choice of material to construct a plastic injection molded part is often a question of budget and the desired end-product. Prior to electric injection machines, steel injection mold were commonly used for mass production.


Today, metal injection mold prices are significantly lower than those of steel. Due to their improved heat dissipation, aluminum mold prices can be used for thousands of parts. Although steel prices are higher than those of aluminum, their long lifespans are usually offset by higher initial costs. High-quality steels are known to endure the stresses of plastic injection molding. Steel injection mold is commonly used for large components, such as lenses. Whether you're looking for aluminum or steel injection molds, TEAM MFG has the expertise to make your project come to life.


Costs of Plastic Injection Molding

The cost of plastic injection molded parts can vary depending on several factors, such as the complexity of the mold, the number of cavities, and the size of the part. The initial cost is usually high, but the final price is relatively low. It's important to note that the quantity of parts used makes a difference in the overall cost.


Variations of Plastic Injection Molding

Although most plastic injection molding procedures are covered by the methods mentioned above, there are also various variations that can be made in the process.

● Co-injection molding

● Thin-wall molding

● Rubber injection

● Low-pressure plastic injection molding

● Inset and outset plastic molding


Plastic Injection Molding Services – Why Choose TEAM MFG

If you're an engineer, designer, or a vehicle parts manufacturer, having a part designed and manufactured using an injected-injection technique can be challenging. At TEAM MFG, we have a team of experts that can help you minimize common mistakes and make smart decisions during the part's development. At TEAM MFG, we're committed to delivering top-quality plastic mold production at competitive prices. Our quality systems and processes help us minimize errors and produce fewer defective parts. Contact us today!

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