What is the difference between 3D printing and plastic injection moulding?
Injection moulding is a common manufacturing process for producing plastic products. It’s…
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15 Injection Moulding Machines
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From small to high-volume production, we can do it all. Whether you’re creating a completely new product or want to change manufacturers, let’s mould success together.
We can produce precise plastic parts from 0.1g to 2000g on our moulding machines that range from 25T to 400T. We have great experience manufacturing complex injection moulded parts that require acute precision. We are certified to ISO9001:2015 and have a proven track record of precision and quality. We bring decades of expertise to the table with advanced injection moulding machines that ensure your product is produced with unmatched accuracy.
We have the expertise to support you – from precision plastic injection moulding to advice on streamlining your manufacturing process to save on costs. Take a look at how we’ve helped some of our clients.
Producing high quality and reliable shrink gun systems
With our flexible approach, we helped ShrinKit manufacture their shrink guns efficiently and in a cost-effective manner without compromising on quality.
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Injection moulding for innovative cycling product
Offering our design, tooling and moulding expertise, we helped Rehook develop their new ‘Rehook Plus’ and ‘Rehook Mini’ products.
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Reducing costs by creating a bespoke mould tool
We helped Advanced Air reduce costs by creating their own mould tool for a bespoke enclosure for their electrical enclosure.
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Injection moulding for plastic casing and components
We are proud to have a long standing relationship with Seneye, creating a system that enables them to monitor water in an aquarium to protect marine life.
Read in full >At Bowles and Walker, we can help you streamline your manufacturing process. We prioritise precision, ensuring every product we mould meets the highest industry standards.
We understand that acute precision is required when creating plastic products for the healthcare industry. Many products for medical or pharmaceutical companies must be moulded in a controlled environment free from dust and other contaminates. At Bowles & Walker, we have a controlled environment room to produce components without the risk of contamination from stray material, dust or other contaminates. We always prioritise quality and precision to manufacture medical plastic components that have tight tolerances and meet industry standards in the UK and globally.
Whether you already have a plastic product you need to manufacture or you’re starting from scratch, we can help. Contact us to get a quote today.
We answer your common questions surrounding our injection moulding services.
Get in TouchWhat is injection moulding?
Injection moulding is the method of injecting molten plastic into a mould, cooling and solidifying it to create a specific moulded shape, and then ejecting it. This technique is commonly used for mass producing plastic parts, and plays a key role in the plastic manufacturing industry. It’s used across a variety of sectors such as automotive, medical, consumer goods, and construction. The parts produced from injection moulding vary greatly in size and purpose, but some examples include car headlight surrounds, plastic syringes, and model airplane parts.
What is the plastic moulding process?
The process of plastic moulding can be complex, and may require other considerations depending on the product, but as a general rule, there are four main stages:
Setup/Clamping – Both halves of the mould are attached to the injection moulding machine plates. One half is referred to as the moving half, while the other is known as the fixed half. Both sides are held tightly together while the molten plastic is injected.
Injection – Plastic pellets are fed into the moulding machine’s hopper, and gravity fed into the barrel. An archimedes screw moves the pellets through the barrel, and the heat and sheer pressure of this process melts the pellets. The molten plastic moves into the nozzle and is injected into the mould itself. When 95-99% of the mould is filled, the injection stops.
Cooling – After the mould is full, the plastic inside begins to cool and harden to the mould’s shape. As it cools, the shape will shrink slightly depending on the material used. It’s important to leave the plastic to cool completely before removing it from the mould.
Ejection – At this final stage, force is used via a stripper plate or ejection pins etc. to eject the moulded product from the cavity of the mould. The product then falls on to a conveyor or is robotically removed for packing or further processing. After this, the mould is clamped shut again and the process starts its next cycle.
What plastic materials can you use for injection moulding?
There is a variety of different thermoplastics that can be used for the moulding process. Bowles and Walker provide a range of options, and specialise in 8 primary materials.
Polypropylene (PP) – Low density, low cost and combinable with other materials. Excellent chemical and fatigue resistance. PP is typically used for packaging, parts, machinery, and textiles.
Acrylonitrile Butadiene Styrene (ABS) – A great choice for structural applications. It’s strong, stiff, and tough, and holds its shape under stress. You’d find this material in lego blocks or keys on a keyboard.
Polycarbonate (PC) – Strong, transparent plastic that has uses in the automotive, electronics, and construction industries for clear protection screens, casing, or covers.
High Impact Polystyrene (HIPS) – HIPs is a blend of polystyrene and a small percentage of rubber to become impact resistant. Used for both commercial and domestic applications such as children’s toys, packaging inserts, and bathroom cabinets, this is ideal for the indoors but not recommended for outdoor uses.
Low Density Polyethylene (LDPE) and High Density Polyethylene (HDPE) – LDPE is soft, flexible, and chemical resistant but can’t handle temperatures over 80°C. It is often used for trays, containers, flexible parts, plugs, and pipes. HDPE has very similar properties to LDPE, but is more rigid and has a better resistance to heat.
Nylon or Polyamide (PA) – As a well known engineering plastic, PA can withstand high temperatures and is a great electrical conductor. These properties make it ideal for fuses and circuit breakers. It’s also commonly used in the automotive industry to reinforce high impact areas in cars.
Polymethyl Methacrylate (PMMA) – Well known as the material behind “Plexiglass”, PMMA is clear, rigid and hard. PMMA is often used in vehicle lights, safety glass, acrylic nails and glass lenses.
If you’re not sure which plastic would suit your project, the Bowles and Walker team are happy to advise you on the ideal material for your products requirements.
How much will it cost?
The cost of manufacturing plastic parts varies greatly. Most of the expenditure goes on design and production of a moulding tool for your product’s requirements. Once the tool has been created, routine plastic injection moulding tends to be a lot cheaper, but this can also vary based on production volume, cost of the plastic material, and the level of precision required. No matter the project, budget or scope, Bowles and Walker will collaborate and consult with you to advise on the most cost effective solution for your manufacturing process.
What are the benefits of injection moulded plastic parts?
There are many advantages to using injection moulding in your manufacturing process. The key selling point is that you can produce a large amount of plastic parts quickly and cost effectively, without compromising on quality. Some other benefits include:
Consistency – With a quality, well cared for moulding tool, you can continue to produce identical plastic parts.
Precision plastic injection moulding – Compared to other techniques, injection moulding allows for more intricate details and features on a very small plastic part. This provides more flexibility and functionality for plastic parts made with this method.
Speed – This varies based on the detail, size, and precision of the required product, but cycle times can be as low as 10 seconds. Other techniques such as 3D printing would take a significantly slower amount of time.
