Improved Production Speed in Tinplate Cans Fabrication

The company contacted Pneumofore early 2006 because they were facing troubles in the in process line of their metal can production. Vacuum for cans production is used for the picking of metal sheets prior to the food grade painting which means an important part of the production process. The major problems that were present were high maintenance costs and time as well as significant production shut down times due to high metal sheet rejection rates. A crucial role to all these problems was the fact that the company, with 8 painting lines had 8 installed rotary vane vacuum pumps of another brand, one in each painting room. The vacuum pumps had a huge oil carry over from the exhaust with consequently deleterious oil presence on the metal sheet surfaces. This caused the high rejection rate of cans, due to the bubbled painting discarded by the QC.

Pneumofore studied the vacuum plant with accessories to meet the customers needs and proposed a centralized vacuum solution consisting of 2 x UV16 air-cooled rotary vane vacuum pumps with 22 kW and 971 m³/h at 50 Hz. The pumps are situated outside of the painting rooms.

The Pneumofore solution showed immediate advantages. Due to no oil carry over from the exhaust, rejection rates were eliminated, painting was not disturbed, QC was happy. Also maintenance was reduced to one ordinary maintenance operation for every 4000 working hours of the pumps. The two pumps alternate work weekly, thus only one maintenance operation per year is needed, lasting only three hours with one local worker instructed directly by Pneumofore. Other additional benefits were the silent operation by only 69 dB(a) whereas the former installed pumps had an annoying noise coming from worn-out vacuum pump vanes.   

Results have been very satisfactory and the customer plans another installation for 12 painting lines for easy-open tin containers.

June 2007