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News in detail

Pwt Ltd: The Patented Innovative Soap Application for Wire Drawing

Published: - 21/04/2014 Author: Dell'Oro, Management
Pwt Ltd: The Patented Innovative Soap Application for Wire Drawing

Rotating Soap Drum

After years of research and development PWT is pleased to bring to the market the most advanced dry lubricant application system. The Rotating Soap Drum (RSD) (Patent Pending) has been carefully designed to meet the needs of modern wire drawing using dry powder lubricants.


The need to have good lubrication on wire during the drawing process is paramount to ensure the metallurgical properties of the steel are not adversely affected. At the same time it is important to maximise the length of time between die changes to allow maximum operating time of the wire drawing machine. Finer powder is very important for effective lubrication. This is one of the main factors having a significant influence upon lubricant residual coat-weights. However, in conventional die-boxes an abundance of fine powder generally leads to tunnelling, which results in reduced lubrication and even lubrication failure. Another factor having significant impact upon lubricant residual coat-weight is the quality of the lubricant being introduced to the drawing die itself. Soap that has already been burned provides a coating far inferior to that provided by unburned soap. Therefore, introducing soap that has a higher proportion of unburned material to the die, allows for a greater quantity of coating to be applied due to the superior melting, spreading and covering capabilities of unburned soap. Under typical drawing practices the lubricant will start to melt and burn within a few minutes of starting the wire drawing machine. Within 1 hour burned lubricant builds up in the lead in tube of the die reducing the lubrication of the steel wire prior to the die. By 3 hours the burnt lubricant is solid in the die lead in tube and often fills the wire corridor leading to the die.




traditional soap drum




New rotating soap drum


The RSD demonstrates the results of thorough mixing, eliminating both zones of contaminant accumulation and areas of uneven particle size distribution, due to the innovative method of dispersion and mixing employed. This good blend of fine and courser lubricant particles are concentrated closer to the wire we are able to maximise lubricant application to the wire entering the die. This lubricant coating can be up to 2 times that of other methods.

The RSD is a fully automated system that has proven to add significant benefits. These benefits include:
- Reduced die wear of up to 55%
- Reduction in temperatures across dies of up to 50%
- Reduced lubricant usage
- Reduced soap dust generation.
- Where current lubrication breakdown restrains wire drawing machine speeds, machine speeds are able to be increased.
- Full automation capability linked to the wire drawing machine.
The new RSD has the real ability to deliver consistency, purity and quantity of good lubricant to allow maximum performance to be achieved in the wire drawing process.