SiroLock™ doffer wire.

SiroLock™: carding solution for fibre control

SiroLock™ doffer and worker wire is a significant breakthrough in fibre processing efficiency.

• 16 March 2010 | Updated 14 October 2011

• Improving the efficiency of carding
• What CSIRO did
• The benefits of new card wire technology
• Commercialisation

Improving the efficiency of carding

Carding is an important step in the processing of staple fibre for both woven and nonwovens products. 

The purpose of carding is to open and disentangle fibre clumps, and assemble the individualised fibres into a continuous web for subsequent processing.

Assembly of carded fibres into continuous webs or 'slivers' is called 'doffing' and involves the transfer of fibre from a high-speed carding cylinder to a low-speed doffer. 

Doffing is a critical step in carding and has a major impact on the productivity of the process and the quality of the product.

The textile industry has known for some time that improving the efficiency of doffing would provide significant savings.

The doffing process is represented schematically in the figure below, which shows the flow of fibre from carding cylinder to doffer.

Illustration of a worsted card, showing the flow of fibres from the card cylinder to the doffer.

For maximum efficiency, the doffer teeth or ‘wire’ must efficiently strip fibre from the carding cylinder and prevent its return to the cylinder.

Also the doffed fibre must detach easily from the doffer teeth so that it can be collected for further processing. Any tendency for the doffer to retain fibre would cause the card to stop.

What CSIRO did

Mr Ken Atkinson (now retired) designed a new profile for doffer and worker wire with 'steps' on the active face that were parallel to the base of the wire (as shown in the image of SiroLock™ wire above). 

Fibres caught on the step were unable to slip off, preventing their return to the carding cylinder.

The steps aided transfer efficiency by increasing retention of fibre by the doffer.

View a demonstration of SiroLock card wire in operation (video).

In addition, with precise timing, the doffed fibre releases allowing the web to slide off the teeth easily and be collected as sliver.

Image of SiroLock™ doffer wire wound onto the doffer, with continuous web of fibre being collected into a sliver.

The benefits of new card wire technology

Processing trials at CSIRO confirmed the benefits of the new design for both doffer and worker wire.

When used as a doffer wire, the trials showed increased fibre length, reduced nep (small fibre entanglements) in the web and combing noil (waste).

Commercialisation

Bekaert, the international leader in carding wire manufacture, commercialised the new doffer and worker wire.

Mr Atkinson worked closely with a team from Bekaert during the development and trialling of the wire.

The new wire technology was released as SiroLock™ at the 2007 International Textile Manufacturers' Association (ITMA07) trade fair.

The international industry had been anticipating the commercial release of the wire and large sales were achieved off-the-stand at the ITMA show.

Find out more about Fibre processing creates new fibrous structures and solutions.