Moulding Process: Centrifugal Force

The rotational molding process is a high-temperature, low-pressure plastic-forming process that uses heat and biaxial rotation (i.e., angular rotation on two axes) to produce hollow, one-piece parts. Critics of the process point to its long cycle times—only one or two cycles an hour can typically occur, as opposed to other processes such as injection molding, where parts can be made in a few seconds. The process does have distinct advantages. Manufacturing large, hollow parts such as oil tanks is much easier by rotational molding than any other method. Rotational molds are significantly cheaper than other types of mold. Very little material is wasted using this process, and excess material can often be re-used, making it a very economically and environmentally viable manufacturing process.


Rotational Molding Process
 The rotational moulding process consists of four distinct phases:
  1. Loading a measured quantity of polymer (usually in powder form) into the mold.
  2. Heating the mold in an oven while it rotates, until all the polymer has melted and adhered to the mold wall. The hollow part should be rotated through two or more axes, rotating at different speeds, in order to avoid the accumulation of polymer powder. The length of time the mold spends in the oven is critical: too long and the polymer will degrade, reducing impact strength. If the mold spends too little time in the oven, the polymer melt may be incomplete. The polymer grains will not have time to fully melt and coalesce on the mold wall, resulting in large bubbles in the polymer. This has an adverse effect on the mechanical properties of the finished product.
  3. Cooling the mold, usually by fan. This stage of the cycle can be quite lengthy. The polymer must be cooled so that it solidifies and can be handled safely by the operator. This typically takes tens of minutes. The part will shrink on cooling, coming away from the mold, and facilitating easy removal of the part. The cooling rate must be kept within a certain range. Very rapid cooling (for example, water spray) would result in cooling and shrinking at an uncontrolled rate, producing a warped part.
  4. Removal of the part.

To learn more about process of rotational moulding or to get in contact with us regarding an enquiry you can find us at our website here, or via email on

Welfare Hire: Explained

Our Welfare Units are extremely popular and are often hired within the construction sector to enable workers to have an warm area with general facilities to eat and drink, alongside additional sanitation options. In order to comply with The Construction (Design and Management) Regulations 2015 (CDM 2015) work areas must see that certain rules are kept.

  • ‍Clean and working toilets
  • ‍Washbasins with hot and cold running water
  • ‍Sinks large enough to wash face, hands and forearms
  • Somewhere to change, dry and store clothing
  • A rest area to sit, make hot drinks and eat food

Our JOBEC Welfare Units are fitted with the following:

  • Large sink with hot water handwash/unit and clean drinking water
  • Recirculating toilet (30 gallons)
  • Recirculating flush toilet compartment
  • Built-in generator
  • Block insulation & heavy duty floor covering
  • Six way consumer unit
  • Microwave cooker & Kettle
  • Steel personnel doors with sliding steel shutter
  • LED interior lighting with electric wall mounted heater with double sockets

Here is our video below that showcases our JOBEC Welfare Units that we provide to many companies around the UK to ensure they are following correct procedure.

Call us on 01922 649 961 today for any questions you may have regarding the rental of our Welfare Cabins or you can speak to us via our contact form here.

A world full of possibilities.

We can supply many different rotationally moulded or vacuum formed plastic products, A one stop shop that includes Tooling, mold-making service for the home, garden, OEM components and engineered products. Materials we commonly use include ABS and Polyethylene including LDPE, LLDPE, HDPE and cross-linked polyethylene) . We can supply on a bespoke basis, a wide variety of plastic products.

Previous & existing customer products include: Garden pond, pots & containers, Cases, for the materials handling industries, Consumer Goods, Barrels, Tanks, Containers, Cabinets, Trays and Totes boxes, Automotive components, Playground parts, Domestic furniture, Toys, Floats, Barriers, posts and barricades, Storage equipment etc.

Rotational moulding has opened up a whole new way of thinking in the plastic industry, allowing for designs that would not have been possible with conventional manufacturing methods. The materials used in the production process are environmentally friendly and fully recyclable. It is precisely the unique combination of material and method that explains the great success of rotationally moulded plastic products.

The word ‘plastic’ is from the Greek word ‘plastikos’ meaning ‘to grow’ or ‘to form’.

Rotational or rotomoulding is an extremely popular and well-used process for producing items that are usually hollow. It’s most often used for very large articles which are usually made in small quantities. Items such as children’s toys, garden furniture, storage tanks are manufactured by rotational moulding.

Rotomoulding uses polymer in a powder form which is introduced into the mould along with any additives such as pigments or finishers. The mould is closed and then spun both vertically and horizontally and moved into an oven.

As the paste starts to melt and the mould continues rotating, it’s flung to the walls of the mould by centrifugal force where it forms a skin. After a fixed period, the mould is removed from the oven and allowed to cool carefully to avoid the product shrinking or warping.


Vacuum Forming is one of the oldest and most common methods of processing plastic materials. Vacuum formed products are all around us and play a major part in our daily lives.
The process involves heating a plastic sheet until soft and then draping it over a mould. A vacuum is applied sucking the sheet into the mould. The sheet is then ejected from the mould. In its advanced form, the vacuum forming process utilizes sophisticated pneumatic, hydraulic and heat controls thus enabling higher production speeds and more detailed vacuum formed applications.

Nature of Use and Limitations

Vacuum forming offers several processing advantages over other forming processes such as injection moulding. Low forming pressures are used thus enabling comparatively low cost tooling.

Since the process uses low pressures, the moulds can be made of inexpensive materials and mould fabrication time can be reasonably short. Prototype and low quantity requirements of large parts, as well as medium size runs therefore become economical.

Unlike other thermoplastic forming processes, where powder or resin are the starting point, vacuum forming uses extruded plastic sheet. With vacuum forming a secondary process may be required to trim the formed sheet to arrive at the finished part. The trimmed waste can then be re-ground and recycled.

What Kinds Of Molds Are Used?

Vacuum forming tools used for prototyping can be made from a variety of materials. The material choice will depend on the application and will vary in cost. At Jobec UK Ltd, we use wood or resin for prototyping as much as possible because it is the least expensive. However, wood does have some limitations and cannot be used in every application.

Production tools are typically made from machined or cast aluminum which are temperature controlled and last indefinitely. In terms of cost, an aluminum tool is much more expensive than a wood prototype tool and sometimes only slightly more expensive than an production resin tool. As a rule, the more detailed or large the part, the more expensive the tool.

In Terms Of Cost, How Does Vacuum Forming Compare To Other Processes?


Tooling Costs Part Costs
Fabrication very low high
Vacuum Forming Low low/med.
Rotational Mold Low medium
Injection Mold high very low


Why Choose Jobec UK Ltd?

Jobec has been involved in the manufacture of high quality vacuum formed and rotationally formed products for over 20 years. We have, between the staff, 40 years experience in the manufacture and supply of vacuum formed and roto formed products. Our broad knowledge base and expertise allows us to supply parts in all commercially available thermoplastics to your specifications. Jobec is also proud of our environmental conscience in the fact that, when performance parameters and customer requirements allow, we work with recycled and reprocessed materials whenever possible.

Acrylonitrile Butadiene Styrene ABS
Polyester Copolymer PETG
Polystyrene PS
Polycarbonate PC
Polypropylene PP
Polyethylene (sheet and foamed sheet) PE

Typical Products Produced

Baths & Shower Trays Pallets
Ski-Boxes Boat Hulls
Machinery Guards Vehicle Door Liners
Garden ponds Tote trays
Parts of vehicle cabs Exterior Shop Signs


Let Jobec UK help form the success of your business!

If you’d like to discuss a project in more detail with us or view some of our products in our portfolio that we have created you can contact us at

Affiliate Websites:

Tanks On Demand

Rotational Moulding Website

Rotational Moulding: The Process

Rotational moulding is the process of creating hollow plastic parts/products, for example, water and fluid tanks, grit bins, road barriers, canoes, boats, floating pontoons, etc.

Screen Shot 2017-10-27 at 14.47.04.png

For more click information, please click here to visit our website.

The benefits of the rotational moulding process is a relatively uniform wall thickness throughout the product and secondly, the hollow moulding can have design and structural advantages difficult or impossible to achieve by other methods such as blow-moulding or vacuum forming.







Components for the Marine & Sanitation Industry

The two primary products that we wanted to share with you today are our one-way single valve manual hand pump, and our one-way manual foot pump, with service kits also available for both items to extend their life.

We believe that we have managed to create a quality product that our customers can use with confidence and reassurance. Both of our items have incredible application and are currently being used in a wide range of different sectors from construction to marine & boating uses.

You can find our products on our retail site, Tanks on Demand

If you want to speak to one of our representatives please don’t hesitate to call our office during work hours (8:30am-5:00pm Mon-Fri). We will be happy to answer any questions you may have about our products.


Pictured: JOBEC Hand Pump


Pictured below: JOBEC Foot Pump





Godiva Festival 2017

Godiva Festival has been and gone for another year running and have smashed last years record with over 179,000 unique visitors over the weekend. Below is the blog post taken from

Published: Sunday, 09 July 2017

Once again, record crowds have taken to the city’s War Memorial Park with over 179,000 visits over the Godiva Festival weekend.Once again, record crowds have taken to the city’s War Memorial Park with

The event’s 19th year saw performances from The Stranglers, Example & DJ Wire and the Darkness across three days, pulling in massive crowds who flocked to enjoy the live performances.

However, Coventry Godiva Festival also saw huge crowds in its Family Field, which this year boasted a race simulator, bugs show, petting zoo and sports try outs!

Councillor Abdul Khan, Cabinet Member for Events, said: “Godiva Festival has once again shown that it continues to grow each year. The festival is a fantastic event and the Events Team, and all those who have helped make the weekend work, have done themselves proud.

“We tried hard this year to really make sure that there was something for everyone and we definitely achieved that.

“Thank you to all those who played their part, including sponsors, partners and staff, to ensure Godiva Festival continues to be the UK’s biggest free family music festival.”

Alongside the stellar line up, Godiva Festival also offered cultural attractions, with Coventry City of Culture Trust’s Cirque Bijou performance including a spectacular highline stunt which amazed audiences.

Laura McMillan, Coventry City of Culture Trust Manager, said: “Bidding for UK City of Culture, you have to show your city has the capacity to hold large scale events and with 179,000 visiting Godiva this year, Coventry has it covered!”

“Tom Clarke, Panjabi MC and Lucy Rose show the diverse range of artists Coventry and Warwickshire has, and the huge crowds participating together is astonishing to see.”

Throughout the weekend, people also took to Facebook and Twitter to say how much they had enjoyed the event.

Example said it was one of the best crowds he’s ever played to: “Love my job. Thank you @godivafestival

Mark @mabmab71 declared on Twitter that Godiva Festival was “Coventry’s finest weekend of the year”

Paul @paulmoped “The people of Coventry should be so proud of the @godivafestival it is so brill.”

Maxine “Well done @coventrycc for putting together one of the best @godivafestival in a long time #cityofculturebid”

IntelligentVA @intelligentVACo “Whenever we go to @godivafestival it just makes me fiercely proud to be from Coventry #LoveCov #ThisIsCov ”

Images from this year’s event can be found on

We’ve love to hear your feedback about the event. Complete our online survey for your chance of winning a £50 Pizza Express voucher.

Coventry Godiva Festival is brought to you by Coventry City Council, supported by Coventry University, and in association with Free Radio, Jaguar Land Rover, BBC Coventry and Warwickshire, Coventry Jubilee Rotary Club, Fargo Village and Coventry City of Culture Trust.

Rotational Moulding: The Process

We can use a range of popular industry materials such as Standard Polyethylene, Cross-linked Polyethylene, Polypropylene, Polyvinyl Chloride, Nylon/Polyamides and Foamed Polymers.

We remove the plastic products from the moulds by releasing the clamps that separate the two tool pieces.

Next the product is taken out and is rigorously inspected for any imperfections, if it passes this quality assurance test it is trimmed and shaped while warm to allow an easier overall process & a smoother more refined finish to the final product.

This is time when Captive nuts, studs and other fittings can be fitted/extracted from the plastic products while they are still warm.

Depending on the size of the product being moulded we can decide which machine would be the most efficient to use. We have two different machines that both have particular pro’s and con’s depending on the type of work we have for them.

To find out more information about what we do please visit us at

To take a look at what products we manufacture visit us at

Festival season is approaching..


We have certainly been busy at Jobec this year and with Festival season approaching fast things are only going to get busier!

We are proud to announce that we are once again supporting Godiva Festival in Coventry, one of the biggest free UK festivals (last year they saw 148k+ people through the door!) as their dedicated supplier for hygiene and sanitation units over the course of the weekend.

The festival is on from the 7-9 July 2017 and features a wide range of acts from ‘The Stranglers’, ‘Example’ and ‘The Darkness’ and many, many more.

The location is at the War Memorial Park on Kenilworth Rd in Coventry, around a 15 minute walk from the town centre and a 10 minute walk from Coventry train station.
There is also 2000 car parking spaces available on the festival site with the entrance off Leamington Road

Find out more about Godiva festival by visiting their website here and if you’re interested then come along! We hope to see you there in July 🙂

More projects & faster turnarounds!

With our rotational moulding machine up and running we are able to take on more projects with a faster overall turnaround.

Almost any colour is achievable, including Fluorescent, Metallic, Sparkle, Granite, Antique, Cast iron and Pewter, Stone, Terracotta, etc. Using a suitable grade of polymer, properties can be achieved such as – Fuel safe, UV protection, Anti-bacterial, Foamed insulation and Flame retardancy.

Mouldings normally have an even wall thickness throughout, but by carefully manipulation during the moulding process, material can be added or reduced in certain areas for best effect. Captive nutsstuds and other fittings can be moulded in place during process if needed. We also offer post-mould assembly and packaging services for customer products and can dispatch direct to end users if required.

Many varied items can be manufactured quite easily by ourselves, items such as:

Water troughs, Cattle and sheep feeders, Spray tanks, Bulk fuel tanks, Bulk water tanks, Mudguards, Furniture, Baths & Spa’s, Bins & Planters, Point of sale displays, Road Barriers, Traffic Cones, Safety sign, Buoy’s, Life rings, Pontoon Floats, Kayak canoes, Horse, Jumps, Boats, Waste bins, Bottle Banks, Sinks, Portable toilets, Urinals, Doors & Framesand Roof boxes etc, The list of items that can be rotationally moulded is almost endless.

Get in touch with us today for a free quotation or simply to discuss any ideas that you may have. Call us on 01922 649 961 or e-mail us at