Standard stainless steel screws have galling issues
Japanese company NARA Machinery manufactures powder-handling machines for various industrial customers around the world. Many of the machines require a high degree of air tightness with firmly tightened stainless steel screws. However, as screws that have powder contact cannot be lubricated, they are particularly susceptible to thread galling issues.
“We previously used standard 304 and 316 stainless steel screws for all our machines, but our customers experienced galling and gorging issues with these screws,” explains Kennichi Johara, Technical Director at Nara Machinery. “The screws also had air leakage issues and required frequent removal for cleaning and maintenance purposes.”
Such issues and maintenance needs resulted in costly procedures and downtime for industrial customers. “In the worst instances, galled screws had to be cut and carefully removed and replaced to protect against dust getting into the machine,” says Johara.
BUMAX overcomes galling issues
“But then we found BUMAX via the internet and tested installing BUMAX® 88 screws on a customer machine in Japan that had experienced galling issues,” says Johara. “Since installing BUMAX® screws, the customer has not reported any issues with galling or air tightness.”
Developing higher-quality machines
Following this successful trial, NARA Machinery has recently built a brand-new machine with BUMAX® 88 screws. “Going forward, we plan to use BUMAX® screws for all new powder-handling machines we manufacture that require air tightness,” says Johara. “This will help our customers avoid the need for costly downtime due to the maintenance and replacement needs related to galling.”
The use of BUMAX® 88 screws has helped NARA Manufacturing to further develop their high-quality powder-handling machines. “We are very happy to have found BUMAX, and I would strongly recommend BUMAX products to other companies that experience similar galling issues,” concludes Johara.