Entinox’s process for stainless steel beer barrels

Entinox, a Spanish manufacturer of stainless steel beer kegs that distributes throughout the Americas, has used a nitric acid-free Bonderite process to set up an innovative pickling and passivating line. The benefits of this line include ideal health, safety, and environmental (HSE) performance, extended bath life over traditional mixed acid pickling systems, and corrosion resistance.

Entinox’s process has been designed for manufacturers that need to remove all scale, iron contamination, and welding oxides from stainless steel to achieve a fully passivated surface with an even, clean, and aesthetic finish.

To maintain food industry HSE regulations and standards, beer kegs must maintain a surface that is totally free from any traces of pickling agents after the process has been completed. Manufacturers are also currently facing the challenge of maintaining the release of potentially harmful substances, such as nitrogen oxide (NOx) emissions in the air and nitrate effluent in water.

Bonderite C-CP 1300 is the latest generation of Henkel’s nitric acid-free cleaning technology. In contrast to common mixed acid pickling systems, which are still widely used in stainless steel processing today, it requires no nitric acid to deliver excellent results. Additionally, it contains no citric compounds, which addresses the growing concern among brewers of residual flavours in the barrels.

Entinox kegs are typically made from 1.4307 (AISI 304L) grade stainless steel sheet, which is a widely used austenitic chromium-nickel steel alloy. After bending, forming and welding, each keg has a surface of 2 m2. Prior to pickling, the barrels are cleaned and degreased using Bonderite C-AK in a spray washer. Bonderite C-CP 1300 is then applied in another spraying step.

Apart from kegs for transportation of beer to bars and restaurants, Bonderite C-CP 1300 has potential to achieve similar cost and environmental benefits in many other markets where stainless steel is processed. Examples span from heat exchangers and chemical process equipment to stainless steel devices and machines for the food and beverage industry as well as applications in the pharmaceutical and semiconductor industries.