By: Jeff Jeffery
Wednesday, January 6, 2016
The challenges of higher-strength steel and lubricants
By: Jeff Jeffery
Among the challenges facing the metal stamping industry is the increased use of high-strength steel (HSS). Because of the lower cost and greater ease of welding and processing, HSS platforms continue to be attractive to automotive makers. While HSS substrates offer many positive aspects, these alloys can be challenging in the pressroom. These alloys possess higher work-hardening rates, higher tensile strengths, and can be thinner than conventional steel. With increased use of more advanced and ultra-high-strength steel, press shops face much higher deformation temperatures, causing more tool abrasion, galling, edge cracking and other issues solved by using “honey oil”.
Historical practices would dictate the use of oil-based lubricants or products heavily fortified with chlorine and sulphur-based EP additives. While these methods may address the forming of the parts, welding and pretreatment processes may be negatively impacted by the increased amount of oil, and cause difficulty in cleaning.
The EPA has begun the process of banning the use of most chlorinated paraffins. A specific end date has not been announced, but an alternative to the product will be necessary in the near future. With the increased use of HSS, press shops have increased the use of chlorinated paraffins that have been the “go-to” solution for these issues for more than 60 years. The EPA considers 99 percent of chlorinated paraffin used in the United States as hazardous and the ban includes their use and import in all metalworking fluids. Lubricant manufacturers are offering new chlorine-free products to help solvesthe issues caused by increased use of HSS and still comply with the latest EPA regulations.
Many companies have been using products containing chlorinated paraffins for a considerable period of time and their operations depend on it. These companies must evaluate their use of these products and adjust both the types of lubricant used and the customary use of these products. By addressing both the bad habits of over-application and transitioning to chlorine-free paraffins, your press-room can be compliant and effective in addressing issues caused by stamping HSS.
Jeff Jeffery is the CEO of IRMCO, a leading lubricant manufacturer. The Precision Metalforming Association (PMA) appreciates and relies on Jeff’s expertise. Join Jeff and other experts at the Deep Draw Seminar, February 23-24, 2016.