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ARMO 2015

Rotational Moulding

Overview

Rotational moulding (often referred to as Rotamoulding or Rotomoulding) is a process used for producing hollow plastic products. By using additional post-moulding operations, complex components can be produced enabling the process to compete effectively with other moulding and extrusion practices.
 
From 13 - 15 September 2015 the BPF will be hosting ARMO2015, an international Rotational Moulding Conference at Nottingham Conference Centre. To find out more and book your place please visit the ARMO webpage 

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contact a moulder

 

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Overview

Rotational moulding differs from other processing methods in that the heating, melting, shaping, and cooling stages all occur after the polymer is placed in the mould, therefore no external pressure is applied during forming.

This provides the following advantages:

  • Economically produced large products
  • Minimum design constraints
  • Stress-free products
  • No polymer weld lines
  • Comparatively low mould costs
 
To visit the BPF Rotational Moulding page Click Here
Balmoral Rotamoulded Tanks
A range of Rotamoulded Tanks


CLICK HERE FOR MORE
EXAMPLES OF ROTAMOULDED
PRODUCTS

The Process

The Rotational Moulding process is essentially split into four operations:

Charging Mould

A pre-determined amount of polymer powder is placed in the mould. With the powder loaded, the mould is closed, locked and loaded into the oven. The powder can be pre-compounded to the desired colour.


Heating & Fusion

Once inside the oven, the mould is rotated around two axis, tumbling the powder – the process is not a centrifugal one. The speed of rotation is relatively slow, less than 20 rev/min. The ovens are heated by convection, conduction and, in some cases, radiation. As the mould becomes hotter the powder begins to melt and stick to the inner walls of the mould. As the powder melts, it gradually builds up an even coating over the entire surface. 
rotational moulding

Cooling

When the melt has been consolidated to the desired level, the mould is cooled either by air, water or a combination of both. The polymer solidifies to the desired shape.

Unloading/Demoulding

When the polymer has cooled sufficiently to retain its shape and be easily handled, the mould is opened and the product removed. At this point powder can once again be placed in the mould and the cycle repeated.

Typical Materials Used


Polyethylene (Low Density)
LDPE, LLDPE

Polypropylene
PP

Ethylene Vinyl Acetate
EVA

Polyvinyl Chloride
PVC

Balmoral Superfill

Typical Products Produced

  • Manhole inspection chambers
  • Rainwater tanks
  • Slides and climbing frames
  • Diesel fuel tanks
  • Childrens playhouses
  • Traffic cones
  • Canoes and kayaks
  • Pallets


CLICK HERE FOR MORE EXAMPLES OF ROTAMOULDED PRODUCTS

Rotamoulded Tank

 

Contact A Moulder

The BPF Rotational Moulding Group represents and promotes the interests of all those involved in the rotational moulding process  (also known as rotamoulding and rotomoulding) - these include small and large sized moulders, material suppliers, machinery manufacturers, ancillary equipment suppliers and service providers.

The information you submit on this form will be sent directly to this group of companies and they will then contact you . Please fill out the form with as much information as possible as this will allow you to receive a timely response.

If you have any queries about this service please contact Sara Cammarano: scammarano@bpf.co.uk or call 0207 457 5013

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Contact:

Tel:  +44 (0)1224 859000
Email: tanks@balmoral.co.uk   
Web: www.balmoral-group.com

We are grateful to Balmoral for their assistance in the preparation of this processes page.