Inox Rubber Mould

Inox Cast has rich experience in handling rubber mould services. We can provide production, export one-stop service for our customers. We export our rubber mould products and other services and offer them with cost-effectiveness.

 We use a good strategy in producing our services, aside from using raw materials, we also pack-well all products in order to provide the most satisfactory products to our customers. Inox Cast is the most excellent company that will give the best service for you.

Inox Cast can provide different designs of rubber mould which allow you to choose the most suitable one for your applications. There are several different types of rubber moulding processes with unique advantages. Inox Cast rubber mould can be performed with the following rubber materials, 

• Silicone
• Neoprene
• Nitrile
• EPDM

We are able to create a variety of moulded rubber products. You will enjoy the great benefits and advantages of this process including minimal material wastage, fast cycle times, fast production time, high-dimensional tolerances.

Inox Cast is a reachable team that can serve you in the time that you need. We offer a service that is suitable for your business budget. With 20 years of experience, we are proud to expose ourselves and offer our products nationwide.

Inox Cast will help you to have a more profitable and sustainable business. If you are interested in our services, don’t hesitate to contact us.

Rubber Mould – The Complete FAQ Guide

This guide is about rubber moulds and their importance in manufacturing rubber parts and products.

Here we will define what a rubber mould is, the materials from which this mould is made, applications, advantages, processes and much more.

1. What Is Rubber Mould?

Rubber moulds

A rubber mould can be defined simply as a tool used to manufacture rubber parts and products.

Manufacturers use it to mould rubber into complex shapes, forms or configurations.

Rubber moulds can be single or multi-cavity, depending on the application.

A single cavity mould produces one product per cycle, while a multi-cavity mould produces more than one.

Their size also varies greatly depending on the product to be formed.

Note that most rubber moulds are designed to use solid materials, e.g. rubber pellets or powder. However, some rubber materials, mainly silicones, can be fed into the mould in solid or liquid form.

2. Common Rubber Moulding Methods

Rubber moulding is the most important curing process in the manufacture of rubber products.

In this process, uncured rubber or elastomer is placed in a heated mould which shapes it into the desired product.

There are three different techniques for moulding rubber.

Rubber Injection Moulding

Rubber injection moulding

This process follows typical injection moulding in which a solid material is heated to a liquid state. The molten material is injected into the mould to shape the final part.

Once the curing is complete, the mould opens to expel the product and closes again to receive the next injection.

Advantages of rubber injection moulding

Rubber injection moulding is the most automated process for forming rubber parts and products.

This method offers several advantages, including.

• Higher-dimensional tolerances
• Improved product finish
• Offers flexibility in color and material
• Fast cycle times and production lead times
• Endless design possibilities

Disadvantages of rubber injection moulding

As with most manufacturing processes, rubber injection moulding has certain drawbacks.

• Requires more expensive tooling and machinery
• Higher set up costs as it is a highly automated process

Transfer Rubber Moulding

Transfer moulding is also an automated process that combines the compression moulding process.

This is where parts are formed by compressing rubber material using a plunger. This sinking action pushes the rubber into the cavity of the desired parts, where it takes on the intended shape.

Transfer moulding

Rubber transfer moulding can also combine injection moulding in a hybrid process.

Advantages of transfer injection moulding

This manufacturing process can be highly cost-saving thanks to using the same preform for multiple cavities.

Other advantages include:

• Greater accuracy and consistency
• Reduced production time since multiple cavities can be used

Disadvantages of transfer injection moulding

• It wastes a lot of material
• Designing complex transfer rubber moulds can be quite costly

Compression Rubber Moulding

As the name suggests, rubber compression moulding uses compression to achieve the desired end product.

The process has been around for over a century and has remained virtually unchanged since its inception.

Like rubber transfer moulding, this process involves rubber “preforms” that take the shape of the final product. These shapes are formed and cured, and the final product is released to restart the compression moulding cycle.

Advantages of compression rubber moulding

Rubber compression moulding has many advantages.

These include:

• Suitable for both low and high volume moulding
• Low setup costs, particularly in low volume production
• Multiple cavities can be used to reduce costs on high volume runs
• Low tooling costs compared to other forms of moulding
• Part design is not limited as with transfer and injection moulding methods
• Minimal material waste

Disadvantages of compression rubber moulding

The only real disadvantage of rubber compression moulding is that the process can be prolonged for the following reasons:

• Material loading time
• Material curing time
• Time required to remove parts from the tool

Which Is The Most Cost-Effective Method For Rubber Moulding?

The best and most cost-effective moulding method depends on your specific circumstances.

Therefore, we often encourage customers to leave this decision to their supplier.

The supplier will be able to decide the method depending on your product design, the quality of finish required, and the volume required.

Generally, though, there is never much contention between injection and transfer rubber moulding. As you know, if a part can be injection moulded, it can also be transfer moulded.

Rubber injection moulding is preferred when larger quantities are produced, while transfer moulding is preferred for smaller amounts.

On the other hand, rubber compression moulding is often considered the most cost-effective process. This is particularly the case in the following scenarios:

• When you already have the required compression moulding tool in place
• When you need to produce a small number of parts/products
• When a large section part needs to be cured for an extended period

Also, rubber compression moulding is ideal when you want to produce all rubber or low profile parts. A compression rubber mould can produce such products more efficiently and in large quantities.

Compared to injection and transfer rubber moulds, it is also the cheapest to build.

If the required parts include a metallic or non-metallic component, or if they must have a cored-out section (s), injection or transfer rubber moulding would be best.

Injection, transfer and compression moulding comparison

3. Types Of Rubbers Used In Moulding Processes

Nitrile rubber gaskets

A wide selection of natural and synthetic rubber materials are available for moulding.

They include:

• Natural rubber (NR)
• Styrene-butadiene rubber (SBR)
• Butadiene rubber (BR)
• Ethylene-propylene-diene monomer-rubber (EPDM)
• Butyl rubber (IIR)
• Polychloroprene or neoprene (CR)
• Epichlorohydrin rubber (ECO)
• Polyacrylate rubber (ACM)
• Millable polyurethane rubber
• Silicone rubber
• Fluoroelastomers

These rubber materials are elastomers and differ from other polymers in their unique properties.

Therefore, material selection is essential for efficient and quality rubber moulding.

Since each project has its unique requirements, it is essential to consider your application when choosing an appropriate rubber moulding material.

Be sure to balance suitability for the application, performance, regulations for its use, cost, and ease of manufacture.

4. Typical Rubber Mould Products And Applications

There are endless uses for moulded rubber products, making them valuable in various industries and applications.

These include oil and gas, aerospace, automotive, military, food, electrical, medical, printing, agricultural, chemical, and commercial.

Moulded rubber parts

Typical rubber moulded parts and products include:

• Electric motor mounts
• Air spring bumpers
• Hydraulic seals
• Pneumatic seals
• O-rings
• Gaskets
• Fenders
• Cable covers
• Keyboard components
• Diving gear
• Surge arrestors
• Casing pipes
• Joint replacements
• Medical tubing
• Catheters
• Grommets
• Automotive bushings
• Baby bottle teats
• Speaker surrounds
• Bottle closures
• Liners
• Diaphragms, pads and rollers (for print)
• Anti-slip grips
• Wiper rings
• Slipper seals and flapper seals
• Tank straps
• Meal trays
• mushroom buffers

5. What Are The Operations Involved In The Rubber Mould Making Process?

The success of any rubber moulding process lies in the mould’s design, manufacture, installation, and operation.

This is the most critical aspect in creating quality rubber moulded parts and products.

The mould itself is part of a more complex machine. The injection, transfer or compression moulding method allows a mould to replenish material and continuously create quality end products.

A typical rubber mould manufacturing process includes the following:

Design

Rubber toy mould

This is the first step in rubber mould manufacturing which involves designing the mould to customer specifications.

Many mould makers have an in-house design team that specializes in this area.

The design team will have the experience and knowledge to work on almost any design project, no matter how complex.

Rubber mould designers will often work on designs using CAD software. Alternatively, they can provide manual drawings if it suits the client’s circumstances.

Typically, several considerations are considered when designing the rubber mould, primarily performance and volume requirements.

Volume requirements will determine the number of mould cavities.

In addition to the design/drawing, a blueprint for machining will also be provided. Usually, the print includes notes, specifications, tolerances, and other essential information to ensure the project’s full completion.

Prototyping

After the design and blueprint are complete, the manufacturer proceeds to make a prototype of the mould. This is also known as rapid tooling or soft tooling.

As the name suggests, parts created by prototyping tools often approximate production prototype parts.

Manufacturers use several metal machining processes to prototype rubber moulds.

They use the same materials expected for the final components manufactured at a low cost. This allows the manufacturer to validate and test them during the early stages of the product development process.

Testing

The prototype is tested to ensure that it meets exact design specifications and project guidelines. These include surface finishes, tolerances, number of cavities, dimensional stability, durability and mechanical properties.

Prototype moulds are generally tested under actual operating conditions.

This facilitates the analysis of the behavior of the mould within the environmental limits defined in the specifications.

Once approved, the idea’s prototype moves into the final mass production run.

6. What Type Of Materials Is Used For Rubber Mould?

Rubber mould

In a mass production process, the rubber mould must be able to reproduce parts accurately and consistently with little waste and high frequency.

The parts’ size, weight, and cure temperature will determine the mould size and material.

Moulds for moulding rubber can be made of plastic or other rubbers.

But mainly, they are made with various engineering-grade metals such as:

• ductile iron
• stainless steel
• mild carbon steel
• aluminum
• magnesium
• tungsten
• brass
• copper

Zinc, copper, aluminum, magnesium, lead, nickel, and tin-based alloys can also make rubber moulds.

7. Advantages Of Rubber Moulding

Rubber moulding is considered a benchmark process for manufacturing a range of parts and products.

This is due to its many advantages, including:

The physical attributes of rubber

The physical properties of rubber, including stability, flexibility, strength, wear resistance, recyclability, and compatibility with other materials, make it ideal for the mass production of components with a wide range of applications.

Eco-friendly

Ideally, rubber moulding processes use very little energy, and most of the rubbers used in this process are easily recyclable.

Therefore, the carbon footprint of moulded rubber components is relatively low.

The lightness of these parts in airplanes, automobiles and industrial machinery further reduces energy consumption.

Low-cost production

Rubber moulding is very cost-effective due to the simplicity of the processes involved.

There is little material waste, and the scrap produced is easily reused to form other parts and components.

In addition, components can be moulded at very high production rates with high precision and tight tolerances.

Material variety

Another significant advantage of rubber moulding is that it allows the use of different types of rubber.

Rubber injection moulding, in particular, allows the simultaneous use of different rubbers. Thanks to co-injection moulding, manufacturers are no longer limited to certain types of rubber.

Automation for Cost-Reduction

Since most rubber moulding processes are automatic, it is possible to save a lot of money.

Most of these processes, i.e. rubber injection moulding and transfer rubber moulding, are done by robotics and machines controlled by one operator. This dramatically reduces the cost of labor.

Automation also increases employee safety because operators do not have to be involved in risky production processes.

Besides, automation allows for accurate and precise rubber moulds with tight tolerances.

8. How To Select The Appropriate Rubber Mould Design For Your Project

The right rubber mould setup for your project will greatly depend on the size and complexity of your part/product.

It will also depend on the expected annual usage, type of rubber, function of the parts and general quantity requirements.

The idea is to choose a mould design that most closely approximates actual production conditions and cost requirements.

Note that more complex part designs will demand a more complex approach to mould design. In this case, it is critical to design the prototype mould cavity as you would the production cavity to save time.

This may turn out more costly.

However, the initial investment will pay for itself fairly quickly through reduced material costs, production times and operational efficiency.

Another thing to note is that multi-cavity rubber moulds are very helpful in reducing production costs and increasing overall production.

A multi-cavity mould is ideal if you intend to produce several parts that will work together and use the same rubber. It can make all components together in one mould, which can help optimize the manufacturing process.

Single cavity moulds are also excellent but only when moulding a few hundred (usually less than 200) parts. The real advantage of the standard mould is that it allows the design or material of the part to be changed at minimal cost before production.

9. Challenges Of Using Rubber Moulds

Rubber moulding presents its fair share of challenges, usually seen as defects in the final moulded parts and products.

They include:

• Short Shots
• Shrinkage
• Flow Marks
• Warp
• Mould Burr
• Burn Marks

These defects occur for several reasons but are primarily due to poor quality rubber mould design. Others include insufficient material supply, poor quality material and inaccurate process parameters.

It goes without saying that working with the right rubber moulding company is imperative.

The right company, in this case, will have experience with both small and large parts. Ideally, a good rubber mould maker should also have skills in different types of moulding, including rubber injection, transfer and compression moulding.

Experience with rubber-to-metal parts, such as electric motor mounts and air spring bumpers, and experience with very complex parts are equally important.

Rubber to metal bonded parts

Most importantly, the right company will have a strong reputation for providing the highest quality components and delivering exceptional reliability.

Inox has experience in all these sectors.

So, by working with us, you can have peace of mind knowing that your rubber products are expertly manufactured and meet the required standards.

Contact us now for all your rubber moulding needs!