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Technical Assistance

If you are having technical issues with your aluminium ROPP’s?.
Such as;

  • Spinning Caps
  • Cocked Caps
  • Damage on application
  • Leakers

Feel free to download the below guides.

ROPP Technical Support Manual
Download our Sealing Technology Booklet here

Fault Finding Poster for the application of ROPP’s
Download our Fault Finding Poster for the application of ROPP’s here

If you are still having trouble we have an excellent team of technical experts.

We are pleased to offer the services of Jim Mansfield to our closure customers.

Jim’s extensive knowledge of the closure market, capping equipment and bottling processes is highly valued by those in the Industry. Jim is recognised as one of the leading experts in the UK bottling industry.


A one day ‘Capping Training’ Sessions can be delivered either at the Viscose site in Swansea or on the clients site and will include a mix of theory and practical experience on capping technology, fault finding and a guide on how to perform torque tests. These sessions are usually attended by members of the operations, quality and production engineering teams. The sessions are relaxed and informal and allow time for each individuals to ask questions and get involved in discussions on common application faults and their root causes and glass manufacturing. Everyone who attends leaves the session enlightened and able to problem solve the typical faults that are seen on the production process.


Whether it’s an annual service for your production equipment or a problem solving requirement, Jim will visit your site and complete a planned maintenance visit or identify the root cause and corrective action required to get you back up and running.


Through a selection of partner organisations, Jim is able to source machinery and spares to get you back up and running, manage transition projects or refurbish your filling lines. No job is too small. Jim brings his knowledge and expertise of working with major brands in the bottling industry to your facility’’.

Storage of ROPP Closures

Look after your Closures

We recommend that RO and ROPP Closures are stored in an odourless, dry and UV- protected atmosphere in sealed cardboard boxes at a constant storage temperature of between +5°C and +35°C (between 41°F and 95°F). A Relative Humidity of 60% should not be exceeded.

Before application onto bottles, we recommended that the closures are allowed to acclimatise for 48 hours in an area where the temperature is held constantly at 20°C +/-5°C (68°F +/-9 °F).

Stored carefully, the closures may be applied safely for up to 5 years from the manufacturing date printed on the box label.

Plastic Closures - HDPE vs PET

Customer sometimes ask us why closures are made from PET and if they were, they could be recycled with the PET bottle.

Let us explain more…

PET and HDPE are very commonly used as packaging raw materials.

PET is also known as PETE or Polyester. PET stands for Polyethylene Terephthalate and is mostly used for the manufacturing of plastic beverage bottles. PET is a very clear plastic and can look like glass once set to its desired shape. PET can also be coloured matched to any colour. PET is, lightweight and tough against gases and liquids. PET is also highly resistant to diluted acids, oils and alcohols. PET has a lower temperature resistance than HDPE. PET containers can handle cold temperatures of about -40°F.

High-density polyethylene (HDPE) or polyethylene high-density (PEHD) plastic is known for its durability and strength. While not as clear as PET plastic, HDPE caps, bottles, containers can be translucent so you can to see your product inside the bottle. This type of plastic can also be colour matched. HDPE bottles are able to withstand low temperatures very well (-110° F) and higher temperatures moderately well near 167°F. HDPE is very stiff, has a good temperature resistance and a very good water vapour barrier.

The most important reason why PET is not used as a closure material is that using PET on PET will not provide an adequate seal for threaded closures. In the past, two piece closures were used for Carbonated Soft Drinks (some two piece closures are still manufactured today). In the two-piece closure system, the liner ensures the cap makes a tight fit to the PET bottle neck, providing a tight seal. Today, this can be achieved with a single piece HDPE organoleptic closure with a bore seal structure.

PET gains strength when it is stretched during the blowing operation. This second operation cannot be achieved in the process of closure moulding which is performed as a single operation.

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