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Everything You Need To Know About Vacuum Forming

Vacuum forming involves vacuum pressure to form a mold or part. This technique has been used for several years in the manufacturing industry and has proven reliable and cost-effective in producing high-quality products.

This article will cover everything you need to know about vacuum forming, from its process to its advantages.

Vacuum Forming Process

The vacuum forming process starts with the creation of a mold or tool. This mold is typically made from aluminum or steel and is designed to fit the product’s shape. Once the mold is created, a sheet of material is placed over it.

The sheet of material is heated until it becomes pliable. Once it reaches the desired temperature, it is lowered onto the mold, and vacuum pressure is applied. This pressure pulls the material onto the mold, creating a perfect shape.

Advantages of Vacuum Forming

Here are the benefits of vacuum forming and why businesses should consider using it as a manufacturing method:

High-Quality Surface Finish

Vacuum forming ensures that the plastic material is evenly distributed within the mold, helping eliminate defects such as air bubbles or voids. This results in parts that have a smooth surface finish and consistent dimensions. It also removes the need for extra finishing operations such as sanding or polishing.

Reduced Material Waste

Vacuum forming minimizes the amount of scrap material created by ensuring that the plastic material is distributed evenly inside the mold. This lowers the cost of raw resources and the amount of waste generated.

Enhanced Design Flexibility

Vacuum forming enables the creation of complex shapes and intricate designs that would be impossible to produce using traditional means. Its versatility allows designers to develop one-of-a-kind parts tailored to their requirements while retaining high quality and uniform proportions.

Faster Production Time

Another advantage of vacuum forming is that it can help manufacturers achieve quicker turnaround times while maintaining high-quality components. This is because vacuum forming allows for the simultaneous production of multiple parts, reducing the overall time required for production.

Reduced Tooling Costs

Compared to other forming techniques, the molds used in vacuum forming tend to be less expensive to produce and maintain. Moreover, the reduced need for additional finishing or quality control procedures increases time and money savings.

Compatibility With Various Materials

Vacuum forming is compatible with various materials, including thermoplastics, thermosetting plastics, and elastomers. This makes it a versatile option for businesses that require different materials for different applications. Using multiple materials also produces parts with specific properties, such as high strength or flexibility.

Transform Your Plastic Parts Production With Vacuum Forming From Lerner Molded Plastics

Looking for a plastics manufacturing partner? Choose Lerner Molded Plastics! Our over 35 years of experience make us a leader in vacuum forming, injection molding, blow molding, extrusion, rotational molding, tool design & build, and complete supply chain services.

Contact us today to learn more about our services! You may also request a quote today to start your next project with us for quality and reliable plastics manufacturing!

How To Choose the Right Plastic Injection Molding Services

Plastic injection molding involves creating a component shape by injecting molten plastic material into a mold under high pressure. It is a versatile and cost-effective method for producing plastic parts in large volumes with high precision and repeatability.

Plastic injection molding services are necessary for businesses that need plastic parts but do not have the in-house capacity to make them. Fortunately, outsourcing plastic injection molding services can provide modern machinery, competent engineers and technicians, quicker production times, cost-effective solutions, and flexibility for changing production demands.

This post will discuss some key factors when selecting plastic injection molding services.

What To Look For in Plastic Injection Molding Services

With numerous plastic injection molding service providers in the market, choosing the right one can be challenging. Here’s what to look for in a company offering plastic injection molding services:

1. Track Record of Excellence

Look for a service provider with a history of producing high-quality plastic parts backed by certifications and testimonials from satisfied customers.

2. Cost-Effective Solutions

Consider the balance between cost and value, considering material quality, production volume, and lead times. This ensures that the provider offers cost-effective solutions that fit your budget.

3. Material Expertise

Assess the provider’s experience with different materials and their appropriateness for your application to guarantee they meet your material requirements.

4. Advanced Equipment and Technology

Advanced machinery and technology can impact the injection molding process’s quality, efficiency, and precision. Hence, inquire about the provider’s equipment and technology to ensure they can handle your project.

5. Production Capacity and Capability

To avoid delays and manufacturing bottlenecks, seek a vendor that can produce your specified components within your set time frame. Also, ask about the provider’s lead times and delivery schedules to ensure they align with your project timeline and can effectively meet your deadlines.

6. Robust Quality Assurance

Look for a vendor with rigorous quality assurance methods — including inspections, testing, and certifications — to assure consistent part quality and industry standards.

7. Effective Communication and Customer Support

Effective communication is crucial for a successful partnership and smooth project execution. Hence, always consider the provider’s communication channels, responsiveness, and level of customer support.

8. Sustainability Practices

If sustainability is important to your project and values, ask about the provider’s waste reduction, recycling, and usage of eco-friendly products.

9. Confidentiality and Intellectual Property Protection

Discuss the provider’s policies and measures for confidentiality and intellectual property protection to safeguard your proprietary information and ensure data security.

10. Location and Proximity

The provider’s location impacts logistics, shipping costs, and communication. Consider proximity to your facility for efficient ongoing projects or interactions. For example, choose a plastic injection molding service nearby for cost-effective operations.

Lerner Molded Plastics: Where Precision Meets Perfection in Plastic Injection Molding!

Lerner Molded Plastics provides high-quality custom plastic injection molding services to customers around the United States. Our team has over 30 years of plastic manufacturing experience and can offer high-quality custom-molded plastic components to satisfy your demands. Our cutting-edge injection molding manufacturing facility produces accurate and dependable plastic parts for various applications. From prototyping to production, we are committed to delivering exceptional results on time and within budget.

Whether you need a small batch or a large volume of custom plastic components, Lerner Molded Plastics has the capabilities and expertise to meet your needs.

Contact us today or request a quote to experience the difference between working with a trusted industry leader.

How To Get Your Custom Injection Mold Done Right

Click to ExpandHow-to-Get-Your-Custom-Injection-Mold-Done-Right

Many businesses can attest to the advantages of working with custom injection mold companies that manufacture parts for a wide range of products. However, injection molding is a complex process with numerous factors to consider to ensure you achieve the ideal output for your business.

To guarantee your project’s success, you need the right planning strategy based on your specifications and a skilled expert partner to handle your custom injection molding processes. This article will dive into everything you need to know to get your custom injection mold done right.

Key Considerations When Getting Custom Injection Mold

If you are thinking about getting a custom injection molding service for your business, here are the factors to consider to ensure the best product:

1. Know Your Project Requirements

Before venturing into a new technique to elevate your manufacturing operations, you must identify the needs of your business. Understanding the intricacies of custom injection molding — including its advantages and disadvantages — and how it’s suitable to your production process help determine the caliber and type of services you need.

2. Select the Right Materials

The injection molding method may be carried out using various plastic resin materials. Because each material has distinct qualities, recognizing their differences is critical to picking the best material for your application.

Here are the most common materials used in the molding process:

Polypropylene

This material is commonly used for injection molding resins due to its versatility. Toys, storage bins, recreational goods, packaging, appliances, and power tool bodies are just a few examples of products that may be made from polypropylene.

Acetal

This plastic is frequently used as an alternative to metals. As a result, it has a wide range of uses, including those for mechanical gears, electrical components, automotive supplies, sports goods, medical equipment, food equipment, hardware, and construction tools.

Acrylonitrile Butadiene Styrene

This thermoplastic is commonly used to manufacture light, stiff molded goods such as piping, automobile body pieces, wheel covers, enclosures, and safety headgear.

3. Find a Reputable Injection Molding Partner

Finding a partner you can trust and whose skills fit your demands will guarantee a seamless manufacturing process and ensure high-quality components. Here are five factors to consider in choosing the perfect custom injection mold partner for your business:

Capabilities and Experiences

The easiest approach to assessing a company’s expertise is to inquire about its capabilities, equipment, and experience. For instance, a manufacturer who has been in business for decades will be able to better meet your demands. You may also ask prospective partners whether they are ISO-certified, as this is an independent verification that they adhere to the necessary industry quality standards.

Equipment Availability

The intricacy of your project will significantly influence your choice of manufacturing partner. They must be familiar with your industry and have the equipment and tools needed to meet your requirements. It is also best if they have clean and modern facilities that ensure your components’ quality and safety.

Timely Compliance

Choose a supplier who can deliver your parts and components within the specified time frame. The manufacturer should also constantly communicate the progress of your orders. Additionally, they have to be able to easily source the supplies needed for the molding procedure to stay ahead of schedule.

Quality-Assured Custom Injection Molding Services From Lerner Molded Plastics

Lerner Molded Plastics provides custom plastic injection molding to customers in various industries across the United States! Our team is an expert in multi-cavity injection molding for complicated components, so we can guarantee that your custom injection molds will be done right the first time.

Contact us today to learn more about our capabilities, or request a quote now.

What Is Rotational Molding?

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Rotational molding, also known as rotomolding, is a thermoplastic molding technique most suitable for large, single-piece hollow objects and double-walled open containers, such as coolers, kayaks, and tanks. It is perfect for entrepreneurs, start-ups, and micro businesses, as it is a cost-effective option for production numbers of fewer than 3,000 yearly.

Rotomolding is often used for components that need high stability, homogeneous wall thicknesses, and high-quality finishing. The rotomold may be easily customized with inserts and spin weld attachments, and foaming can be utilized to add rigidity and thermal insulation. With no pinch-off seams or weld lines, rotomolding creates a completed product without needing supplementary procedures, unlike blow molding and thermoforming.

How Does It Work?

A rotational molding procedure involves the following steps:

1.    Pulverizing

Pellets or coarse powders are milled or pulverized to produce a fine or extra-fine powder. Since the particle sizes of various machines vary, the plastic material must be processed through numerous pulverizers to attain the desired uniformity.

Batch pulverization, dry milling or grinding, and wet pulverization are all types of pulverization. The pulverization method is determined by the molding process to which the pulverized plastic will be subjected.

2.    Loading

The polymer, a powdered resin, is metered and tightly pressed into a hollow mold. For a proper flow and to avoid bubble formation, the powdered resin must be dry, homogenous, and in fine particle sizes. Therefore, one of the elements affecting the part’s wall thickness is the amount of resin loaded.

3.    Heating

In this stage, the powdered resin is heated while gently rotating inside the hollow mold until all the resin is melted. The interior wall of the mold is also completely covered with resin as it melts. Moreover, the mold’s resin is distributed uniformly because of the simultaneous heating and rotating actions, and the biaxial mold rotates at a modest speed of approximately less than 15 rpm.

The polymer heating time is crucial, and one of the criteria is influencing the quality of the completed product. For instance, the polymer will thermally degrade if it is heated for a long time, lowering its final mechanical attributes and making it less resistant to wear and impact.

On the other hand, if the heating process is rushed, the polymer will only partially melt. As a result, unmolten grains won’t combine with molten resin, which causes bubbles to develop. This fluctuation negatively impacts the product’s end-mechanical qualities.

4.    Cooling

At this point, the liquid polymer inside the mold hardens and takes on the intended shape. Next, the outside of the rotating mold is cooled by using air, either forced or natural convection. To preserve dimensional stability during cooling, cooling air is occasionally delivered to the interior of the mold. Using water sprays to speed up cooling might impact the part’s mechanical characteristics and size.

The polymer’s cooling time is just as important as its heating time. As a result, the correct cooling rate must be established. Rapid cooling causes the component to deform and shrink out of control. Meanwhile, slow cooling results in the flow of the molten resin, which results in uneven wall thickness.

5.    Unloading or Demolding

The operator carefully removes the cooled portion from the hollow mold tool. Then, the part can be lifted out of the tool with an air ejection mechanism. Following the removal of the pieces, other procedures — including inspection and packing — are carried out.

6.    Secondary Processes

The application of the produced product determines which kind of secondary procedure is used. This can involve assembling, welding, coating, painting, adding inserts, etc.

Key Benefits

Rotomolding can be more beneficial than conventional molding techniques. Here are some of its advantages:

Cost-Efficient Tools

There is no pressure applied in rotomolding because the process involves casting. As a result, molds are affordable and low-volume production may be profitable.

Because of its inexpensive initial expenditure, rotomolding is particularly appealing if you have a brilliant concept for a new product but are unsure how many you will sell or need a low-volume production run.

Operational Ease

In rotomolding, complex forms are simple to create. Production complications — including stiffening ribs, molded inserts, and various surface textures — are easily accommodated by this technique.

Consistency and Uniformity

Rotomolding produces uniformly thick walls, with often thicker corners that improve the integrity and strength of the product. Other techniques, like blow molding, strain the molten material at corners or sharp edges, potentially causing weak points and thin places.

Production Flexibility

Rotomolding allows a single machine to simultaneously mold many pieces. Tool management is simple, with some rotational molding equipment that includes independent arms; one mold may be scheduled for maintenance while the others are in operation.

Lerner Molded Plastics for High-Quality Rotational Molding Services

Lerner Molded Plastics is an ISO 9000-2000 certified plastic injection mold and tooling maker with over 25 years of expertise! We also provide rotational molding services to customers in various industries.

Plastic injection molding may be a complex procedure with many variables to consider. We can walk you through these factors and assist you in deciding on the optimal injection molding tools and component design for your project.

Contact us today and discover how we can assist you, or request a quote to get started with us!

Understanding the Plastic Injection Molding Process

Click to Expand Understanding the Plastic Injection Molding Process

Injection molding is one of the most widely used methods of processing plastic materials. It is a complex manufacturing process in which plastic is melted, injected, and set into the shape of a metal mold using a hydraulic or electric machine. This method is beneficial for the mass production of products with intricate shapes and is commonly applied in automotive, home appliances, and medical devices.

This article will dive into the fundamentals of plastic injection molding — including its definition, advantages, and step-by-step procedure.

What Is Injection Molding?

Injection molding is a fabrication procedure that enables the production of large quantities of parts, and it entails injecting molten materials into a mold. Materials used in this process typically include metals, glasses, elastomers, and confections, though thermoplastic and thermosetting polymers are the most commonly utilized.

Plastic injection molding has the following advantages:

Flexibility

Manufacturers can select the mold shape and thermoplastic utilized for each component. Thus, the injection molding process can create a wide range of items, including extremely complex parts.

Efficiency

Injection molding machines can uniformly produce thousands of pieces per hour once the operation has been set up and tested. Using electric injection molding machines also contributes to the process being relatively energy efficient.

Quality and Consistency

Plastic injection molding can consistently manufacture strong, ductile, and finely detailed components quickly as long as the process parameters are tightly controlled.

Cost-Effectiveness

Once the mold has been built, the production cost per component will be reduced, particularly if large quantities are produced.

How Does Plastic Injection Molding Work?

Plastic injection molding is performed in highly specialized injection molding machines (IMMs) fitted based on mold clamping force in tons. These machines can range from micro IMMs that generate exceedingly small parts in small molds to very large IMMs with clamping forces surpassing 3,000 tons.

Here is the step-by-step procedure for injection molding:

Step 1: Choosing the Right Thermoplastic Material and Mold

Selecting the appropriate thermoplastic materials and molds is critical because they are essential in creating and forming the final components. To make the best choice, manufacturers must consider how the thermoplastic and mold react to one another, as certain plastic types may not be suitable for particular mold designs. For instance, if a manufacturer requires a lightweight part with dielectric properties, polycarbonate will be appropriate, but only if the mold does not need to operate at temperatures above 135 ℃ or extremely high pressures.

Step 2: Feeding and Melting the Thermoplastic

Molding machines typically include a feeder at the top, a cylindrical heated barrel in which a large injection screw sits, a gate at the end of the barrel, and the mold tool to which the gate is connected. The process begins with supplying raw thermoplastic pellets into the feeder. Then, these pellets are processed gradually into the machine’s barrel as the screw turns, steadily warming and melting the thermoplastic.

Step 3: Injecting the Molten Plastic into the Mold

When the molten plastic reaches the barrel’s end, the gate closes, and the screw retracts — allowing a predetermined amount of plastic to pass through. At the same time, the two mold tool components are clamped together and held under high pressure. Once the proper pressure is applied to the tool and screw, the gate opens, the screw advances, and the molten plastic is injected into the mold.

Step 4: Holding and Cooling

After most of the plastic has been injected, it is held under pressure for a predetermined time. This process is called holding time, which can span from milliseconds to minutes, depending on the material. This holding time is critical for ensuring that the plastic packs out the tool and forms properly.

Then, the screw retracts after the holding phase, releasing pressure and enabling the part to cool in the mold. This step is called cooling time and can range from a few seconds to several minutes. It ensures that the component sets properly before being ejected and completed on the manufacturing line.

Step 5: Ejecting and Finishing

Pins or plates eject the parts from the tool after the component is formed. These parts fall into a chamber or onto a conveyor at the machine’s base. Then, other devices and equipment can complete finishing processes — such as polishing, dying, or removing excess plastic. Once these processes are completed, the components will be packaged and distributed to manufacturers.

Exceptional Plastic Injection Molding Services From Lerner Molded Plastic

Lerner Molded Plastics offers custom plastic injection molding to customers in a wide range of industries across the United States! We also take pride in having over three decades of plastic manufacturing expertise and a state-of-the-art injection molding facility.

Our company’s professionals specialize in multi-cavity injection molding for complex components. This production method allows the construction of multiple parts per production cycle, resulting in increased efficiency and shorter production times without compromising product quality.

Contact us today to learn more about our capabilities, or request a quote to get started with us!

Plastic Tooling for Injection Mold Design

Plastics Manufacturing Experts.

A Guide to Plastic Tooling for Injection Molding

Click to Expand Plastic Tooling for Injection Mold Design

Injection molding is a key manufacturing process for most modern industries. It is a versatile process that manufacturers can customize to achieve different end products. To settle on a particular injection molding design, companies should decide on the type of mold, final product quality, and the end-use application. We’ll discuss these considerations here to help you determine the best injection molds and tooling for your production needs.

Types of Plastic Injection Molds

There are several different types of plastic injection molds, depending on their feeding system, cavities, and mold opening:

  • Feeding system
    • Hot runner injection mold: This type of injection mold has a heated channel that guides the molten plastic into the tool cavity. The runners are part of the mold and the temperature is kept above the plastic’s melting point to keep the material liquid.
    • Cold runner injection mold: Cold runner injection molds use an unheated physical channel directing the liquid plastic into the cavity. The runner is cooled and ejected with the part after each injection cycle.
  • Number of cavities
    • Single cavity: Single cavity molds produce one part per injection cycle. Tooling costs are low, while unit cost is higher. These molds are best for low-volume production runs.
    • Multi-cavity: With a multi-cavity mold, multiple parts are made per cycle, which raises initial tooling costs and lowers the per-unit price. Thus, multi-cavity molds are an effective way to increase production.
    • Family mold: A family mold produces at least two different parts in a single injection cycle.
  • Mold opening
    • Two-plate mold: Two-plate molds are the most common type of mold opening, where two plates join and split at a parting line.
    • Three-plate mold: Three-plate molds have two parting planes that split the mold into three sections.

Design Considerations for Injection Molding

There are several injection mold design considerations that may affect the final product quality and process repeatability, including:

  • Size. Injection plastic molding has a maximum shot size, which limits the amount of molten plastic that can be injected per cycle. Shot sizes can range from 3 oz to 600 oz.
  • Materials. There are many different materials you can use, and each behaves uniquely during the injection molding process and results in different final products. Materials include acetal, high-density polyethylene (HDPE), polycarbonate, acrylic, nylon, polypropylene, and more.
  • Surface finishes. Injection molding can produce parts with various surface finishes, from textured to matte to glossy.
  • Color matching and secondary finishing. Customers can also request that part colors match certain Pantone numbers or other samples. Other secondary finishing services include pad printing—to add company logos—and laser engraving for part traceability purposes.
  • Draft. Adding drafts to the mold facilitates easier removal of the part after each injection cycle.
  • Undercuts. Undercuts are part features that cannot be injection molded with a basic two-part mold because the material itself prevents ejection or blocks the mold from opening. The injection mold design must take undercuts into consideration by either avoiding them or redesigning the existing mold.
  • Wall thickness. The ideal wall thickness is based on the material you select. For example, the recommended wall thickness for injection molding with ABS is 0.045 to 0.140 inches, which differs from the 0.030 to 0.120 inch recommended thickness for acetal injection molding.
  • Radii. Adding radii means rounding out sharp corners, which allows the material to flow easier and makes the part easier to remove.

Plastic Tooling for Injection Molding Applications

Injection Machine

Applications for injection molding include:

  • Consumer goods
  • Medical devices
  • Electronics
  • Packaging
  • Telecommunications
  • Mechanical parts
  • Decorative products
  • Firearm components
  • Furniture
  • Hardware
  • Pet products
  • Pressure transducers
  • Toys
  • Window components

Plastic Tooling for Injection Molding From Lerner Molded Plastics

With over 25 years of experience, Lerner Molded Plastics is an ISO 9000-2000 certified manufacturer of plastic injection molds and tooling. We offer injection molding, tooling, and mold-making services to customers across diverse industries. Our capabilities range from small, precision tools to large, multi-cavity tools that include aluminum tooling prototypes. We also fabricate assembly and check fixtures.

Plastic injection molding can be a daunting process with many options to choose from, but we can guide you through these considerations and help you decide on the best injection molding tooling and part design for your project. To see how we can help, contact us today. If you’re ready to get started, request a quote.

Reshoring Plastic Manufacturing in the USA

In the late 1970s, the increase in global competition, the deficit in trade, and the dismantling of trade barriers led many manufacturers in the United States—including plastic manufacturers—to offshore their operations in an effort to lower production costs. By moving manufacturing operations to China and other overseas countries, they could take advantage of cheaper labor, faster turnaround, and looser regulations. However, over the years, increasing awareness of the inherent problems associated with offshoring—e.g., language/cultural barriers, poor product quality, risk of IP theft, supply chain delays, etc.—have led many manufacturers to look to reshoring their operations to improve cost of ownership. Additionally, with increased pressure to level the playing field, tariffs have been put in place on all Chinese imports, that have lessened the overall competitiveness that China has enjoyed. The field is now ripe for reshoring to blossom.

Plastics Manufacturing Experts.

What Is Reshoring?

Reshoring—also sometimes called backshoring or inshoring—is the opposite practice to offshoring. It involves bringing manufacturing operations that were previously outsourced to overseas countries back to the home country of the company. Either some or all of the offshore operations can be returned, depending on the needs and desires of the company.

Why Should You Choose Plastic Manufacturing in the USA?

Reshoring Plastic Manufacturing In The USA

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While the significant cost of reshoring manufacturing operations may be a deterrent to many companies, the practice offers a number of advantages that can help offset it, such as:

  • Lower total cost of ownership. While offshoring manufacturing operations initially proved to be more cost-effective, rising labor, newly enforced tariffs, and shipping costs have reduced the cost-savings experienced by choosing offshore over onshore/reshored manufacturing. Additionally, by reshoring operations back to the USA, companies can avoid paying import and export tariffs on their goods, which can be as high as 25–35%.
  • Higher product quality. Overseas manufacturers may not have access to the same quality materials and equipment as those found in North America. Additionally, the standards they uphold may not be as high as those upheld in North American facilities. Working with a manufacturer with a US-based facility ensures each aspect of the manufacturing process will be conducted as per US industry standards. It also makes it easier to maintain control and oversight over operations.
  • Shorter lead times. Moving manufacturing operations to domestic soil decreases the time it takes for finished products to be delivered to domestic distribution facilities and end-users. It also decreases the risk of shipping delays caused by global supply chain and shipping disruptions.
  • Better tooling ownership. In the United States, most manufacturers deliver the tooling (e.g., molds) used to make custom products to the client after the project is completed. This practice allows the client to choose whether they work with the same company or a different company in the future. It also minimizes the risk of other clients getting a hold of the custom product design.
  • Greater local/domestic benefits. Reshoring generates more domestic job opportunities with regard to product manufacturing, distribution, sales, servicing, and integration and ensures the taxes paid by the company go toward improvements within the country.
  • Smaller risk of IP theft. Sending proprietary designs to another facility operated by a separate company in a different country increases the risk of unauthorized persons accessing, stealing, and copying them. Onshore/reshored manufacturing operations eliminate this risk by ensuring designs are sent to domestic facilities with stricter security standards.

The above benefits both manufacturers and customers. Since the manufacturer encounters lower ownership costs, receives higher quality products, and experience shorter lead times, their customers can be given better products at lower prices with faster turnaround.

Reshore With Lerner Molded Plastics Today!

Today, a growing number of US corporations are transitioning from offshore to reshored plastic manufacturing operations. Additionally, more and more companies are choosing to work with manufacturers with onshore or reshored manufacturing operations rather than offshored ones due to the many advantages they offer.

If you’re looking for an experienced and knowledgeable US-based plastic manufacturer, turn to the experts at Lerner Molded Plastics! We specialize in plastic manufacturing, offering molding, forming, assembly, design, tooling, and supply chain services. To learn more about our capabilities or discuss your project requirements with one of our team members, contact us or request a quote today.

What Is Plastic Injection Molding?

Plastic injection molding

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Plastic injection molding is a manufacturing process that involves the process of injecting melted plastic resins into a prefabricated mold to create a variety of parts and components. This highly versatile and cost-effective process is used to manufacture a variety of products, from children’s toys to complex engineering components.

For more than 35 years, Lerner Molded Plastics has been a leading provider of plastic injection molding services for customers in a wide range of industries. Our state-of-the-art facility allows us to produce quality injection molded parts from the initial design phase through full-scale production and distribution. Whatever your needs, we have the knowledge and skill to create your product or component with the utmost speed and efficiency, all while staying within your budget.

To help you determine whether plastic injection molding is the right choice for your project, we have created a comprehensive guide to the plastic injection molding process, materials, and benefits.

Plastic Injection Molding Process

Plastic injection molding uses high pressure and heat to force melted plastic into a heated mold, where it takes on the desired shape as it cools. The cooled product is smooth and often requires very little additional processing. Although the details of the process may vary depending on the product and material, the plastic injection molding process typically follows these six steps.

1. Mold Creation

A mold is manufactured from a durable, heat-resistant material such as aluminum, steel, or beryllium-copper alloys. Molds are typically CNC machined and finished to extremely precise dimensions to ensure highly accurate and repeatable molded products. Injection molds can be designed with single or multiple gates, through which the melted plastic is injected, and must be able to open on a hinge or sandwich design to allow for part ejection once it has cooled.

2. Clamping

To ensure that the mold does not expand, contract, or become separated when exposed to the high temperatures and pressure of injection molding, the mold must have a secure clamp. The clamping force must be calibrated to ensure that the melted plastic can be injected with enough force to completely fill every part of the mold without material leakage.

3. Injection

The injection process is initiated when plastic beads, powder, or pellets are placed in a hopper, which feeds the material into a heated barrel, causing the plastic to melt while the turning screw simultaneously propels it toward the injection head. The injection head deposits a specific amount of molten resin into the mold at high pressure to ensure that the mold is completely filled.

4. Cooling

After the resin is injected into the mold, the mold is allowed to cool. The plastic hardens as it cools, solidifying into the desired shape. The cooling process is calibrated to ensure that the material cools at the right pace to produce optimal shape, hardness, and surface finish.

5. Ejection

The cooled part is ejected from the mold using built-in ejection pins. It is important to ensure that the part is thoroughly cooled in order to avoid damage. Ejection timing is based on the required cooling time for a given part’s size, shape, and material.

6. Finishing

Plastic injection molded parts are ejected with a smooth surface that requires very little finishing, though specialty coatings and finishes may be added for specialized applications. Most often, the only finishing necessary is the removal of excess plastic around the channels where the resin was injected.

Plastic Injection Mold & Plastic Components for the Electronics Industry

Common Materials

Plastic injection molding can be used to manufacture parts from a wide range of materials, including:

  • High Density Polyethylene (HDPE). A versatile, affordable thermoplastic with high tensile strength and stiffness, HDPE is waterproof, resistant to microbial growth, chemically resistant, and offers good electrical insulation.
  • Polypropylene (PP). PP is a rigid, crystalline thermoplastic valued for its high strength-to-weight ratio, stiffness, electrical resistance, and chemical resistance. It also bears stress and has high impact resistance.
  • Polystyrene (PS). A low-cost thermoplastic with high strength and exceptional clarity, PS is useful for clear packaging and lab equipment, or can be colored for use in consumer products.
  • Nylon. Nylon is an extremely versatile thermoplastic blend that can be tailored to meet the needs of particular products. Nylon blends are extremely tough, with high chemical and thermal resistance and low friction.
  • Acrylonitrile butadiene styrene (ABS). ABS is an affordable engineering thermoplastic valued for its structural strength, stiffness, impact resistance, chemical resistance, thermal resistance, and electrical insulation.
  • Acetal. Acetal isa strong, tough semi-crystalline thermoplastic with exceptional chemical resistance, high mechanical stability, extreme creep resistance, and a low friction coefficient.
  • Polycarbonate (PE). PE is a highly durable amorphous thermoplastic with extreme dimensional stability, good impact strength, exceptional optical clarity, and good electrical insulation.
  • Polyester (PET / PETG). Polyester is an extremely stress-resistant semi-crystalline thermoplastic with high dimensional stability and exceptional resistance to chemicals and heat.
  • Acrylic. Acrylic is an extremely transparent thermoplastic with high resistance to UV radiation, exceptional impact strength, and high dimensional stability.

Advantages of Plastic Injection Molding

Plastic injection molding is an extremely efficient and cost-effective process that can be used to create extremely complex components with a high degree of accuracy and repeatability. Some of the benefits of plastic injection molding include:

  • Efficiency. Plastic injection molding uses the same mold for multiple runs, making it a quick and efficient way to produce multiple components. In addition, products straight out of the mold typically have a smooth finish that requires very little additional processing, thereby reducing time and labor.
  • Accuracy. Since the plastic resin is injected into the mold at high speed, it is forced to fill every cavity in the mold, ensuring extreme accuracy on even the most complex components.
  • Less Waste. Leftover thermoplastic material from the plastic injection molding process can be added to the next load, thereby eliminating process waste. In addition, many of the thermoplastics used in injection molding are recyclable, reducing overall waste.
  • Low Costs. Injection molding uses the same molds for multiple products, making it less expensive than many other manufacturing processes.
  • Variety of Material and Color Options. A wide variety of plastic materials and blends can be used in the plastic injection molding process to create products in nearly any color.

Plastic Injection Molding Industries and Applications

The versatility, accuracy, repeatability, and many other benefits of the plastic injection molding process make it a popular manufacturing choice for numerous industries, including:

  • Building and construction for pipes, fixtures, hand tools, pulleys, and sprockets.
  • Food and beverage for packaging, bottles, line process equipment, and dispensing equipment.
  • Medical and pharmaceuticals for medical devices, surgical implements, and packaging for medical equipment and pharmaceuticals.
  • Automotive for interior handles, knobs, and fixtures.
  • Consumer goods for appliances, garden supplies, tools, furniture, and decor.
  • Housewares for disposable and reusable silverware, plates, bowls, cups, and mugs.
  • OEM for custom-designed mechanical and engineering components.
  • Toys for building blocks and other brightly colored children’s toys and games.

Expert Plastic Injection Molding Services From Lerner Molded Plastics

At Lerner Molded plastics, we pride ourselves on providing our customers with the highest quality injection molding services and materials in the industry. From very small tight tolerance parts to extremely large products requiring high tonnage clamping forces, we have the equipment and experience to handle any size part requirement. As an industry-leading plastic injection molding company, it is our goal to ensure reliable, repeatable products that meet even the most stringent industry standards and specifications. Whether you are in need of large-scale production of a simple toy design or intricate custom OEM components for industrial manufacturing, we have the equipment, experience, and skill necessary to provide you with exceptional quality components every time.

To learn more about our superior plastic injection molding services, contact the experts at Lerner Molded Plastics today, or request a quote for your next project.

Mold Large Plastic Parts

If you want to know how to mold large plastic parts with precise, cost-effective methods, Lerner Molded Plastics can help. Lerner is a leading manufacturer of large plastic parts in Northeast Ohio.

Our staff combines countless years of experience in the plastic parts manufacturing industry. So, we can offer our customers the highest quality for their components. We also offer competitive prices to remain within your budget.

Lerner provides a wide variety of high-precision molding processes to create the parts you need. Our manufacturing processes include injection molding, blow molding, compression molding, extrusion molding, rotational molding, and thermoforming. Additionally, we offer custom coloring services for thermoset and thermoplastic processing.

Large Injection Molding Companies

Lerner Molded Plastics is a leading provider of injection molding services for larger components. As one of the leading groups of large injection molding companies, Lerner offers each client the highest possible quality for their injection molded parts. Our injection molding capabilities enable us to develop large part injection molded solutions for any industry or application.

With a state-of-the-art, ISO Certified facility, we deliver high-quality injection molded parts in a wide variety of plastic materials. Lerner also specializes in complex, multi-cavity molds. As a result, we can fulfill requirements for products ranging from small to very large with shot sizes from 3 to 600 ounces. Our facility houses advanced injection molding machines with clamping forces ranging from 30 to 3,000 tons and up to 64 cavities.

Additionally, Lerner offers injection molding processes for thermoset and thermoplastic materials with custom colors. We are a full-service provider of injection molding services, so we can assist with every stage of the process, from engineering to product development. Furthermore, Lerner offers tooling and mold making as well as finishing, logistical support and supply chain management services.

With 25+ years of experience as one of the leading large injection molding manufacturers, we can help you create exceptopma; designs to maximize quality and minimize production costs. We also offer a veriety of high-quality plastic materials:

  • High-Density Polyethylene (HDPE)
  • Polypropylene (PP)
  • Polystyrene (PS)
  • Nylon
  • ABS
  • Acetal
  • Polycarbonate (PE)
  • Polyester (PET/PETG)
  • Acrylic

Lerner has the equipment an resources to help you create the components you need, regardless of your industry or application.