If you are one of the growing number of UK companies looking to bring previously offshored moulding work back into the UK, then this blog should help you to decide the best way to achieve your goal.
Who owns the Mould Tool? The first consideration is tooling. To tie you in to a Far Eastern based contract, you may have been offered a cheap or even free mould tool. This means that you don’t own the tool, so your priority is to source a replacement. If you have a detailed drawing of the tool or moulding, then this is straightforward. Reverse engineering from a sample is the other way to go.
If this is a new project, you may want to start off by establishing contact with a specialist Product Design & Development company, before moving on to Prototype Tooling. You may still want to do this if you are replacing an existing tool, as it makes sense to improve a product or reduce manufacturing costs if you are going to the expense of re-tooling.
Where should production be moved to? Before deciding this, you should consider:
– The number of items to be produced and the volume of each item to be manufactured. If you know the cycle time of each product, production times can be calculated. For example, a requirement of 10,000 of product ‘A’ per month, which has a cycle time of 30 seconds will require 30/60 x 10,000 = 5000 production minutes (around 83 hours plus setting up time).
– The size of the product(s) and associated tooling. This will dictate the tonnage (clamping force) of the injection moulding machine(s) needed. This chart provides indicative figures for common material grades in terms of clamp force per square centimetre of product surface area. (Surface area of the plane of the moulding that has the material injection point).
Some basic calculations will tell you how many machines are needed to meet your requirements, as well as the size (tonnage) of the machine(s). You need to bear in mind that making widely differing (in terms of size and weight) products on the same machine is not practical.
You now have two options:
- Use a Trade Moulding company. These companies are happy to store your tooling and put it into production against any orders you place. They will be able to quote a price based on their sourcing the raw material on your behalf, manufacturing the components and then shipping them to you. They will already have all of the equipment required to produce your components, so your upfront investment is minimal.
This link takes you to the main Injection Moulding section of the PlastikCity site. There are 18 pre-approved companies that can be sorted by location, size of machines and their particular specialities. With some basic information, you can obtain multiple quotes for your moulding work.
- Create an in-house moulding facility
If volumes are sufficient, you may want to consider creating your own mould shop. Considerations include:
– Do you have sufficient space for raw material, machines and finished product?
– To be efficient, mould shops typically need to run more than one shift
– Availability of sufficient three phase power
– You will need the right skill sets. If you have staff that already work with e.g. CNC machining centres or modern die-casting equipment, then the learning curve will be shorter. If this isn’t the case, you will probably need to employ an experienced technician.
If the answers to the above questions are positive and you also have funds available, then you can begin a costing exercise. Below are a list of the main equipment and service requirements associated with a modern injection moulding facility. In each case, a link is provided to companies that can assist you with sourcing the item.
– Moulding Machines and possibly robots for part removal. Smaller and less delicate components can be dropped in to a box or onto a belt conveyor. Robots can be supplied by the machine OEM, or by a specialist third party.
– If your machines are hydraulic or use hybrid technology, a supply of cool water will be needed for heat exchangers. Some all-electric equipment still requires a small amount of cooling for servo motors. Water can be at ambient temperature for this purpose if you have e.g. a water tower or ‘free cooler’, or you can use a Water Chiller (see below).
– Chilled water and sometimes also water heating equipment (temperature controllers) for regulating tooling temperature. You can use this handy calculator to determine the size of chiller needed.
– Compressed air, particularly for larger machines or if you are using robots.
– Pipework for the transfer of water and air.
– Material drying equipment. Some plastics require drying before they can be processed. Hot air dryers are not recommended for this purpose. Some plastics such as polypropylene and polystyrene don’t require drying providing they are stored correctly.
– Material handling, e.g. to transfer raw material from dryers or storage bins into the injection moulding machine hopper.
In conclusion, bringing moulding projects back to the UK can only have a positive outcome, regardless of how you get there. An unfavourable exchange rate and the possibility of import tariffs on the horizon are probably the main drivers for this decision, but there are other more positive reasons to reshore your work:
– Transportation costs – you don’t have to order a full load to get the best price.
– Reaction times – if you have a run on a product line, you won’t have to pay for expensive air freight. The same applies if you have a quality issue.
– Last but not least, you are manufacturing in the UK and helping to strengthen our economy.
Need more help?
PlastikCity have an experienced team that can help you find the right trade moulder or provide advice on how to specify equipment. Click here to contact us.