Enclosing a nail sorting machine
The problem
An engineering firm, manufacturing components for conveying systems, has developed a batch collation system which takes in nails from an adjacent washer and aligns them using a vibratory feed system. The nails are first shaken up a spiral to the top of the machine and then aligned into collation boxes along a vibrating chute.
Although very effective, the machinery generated A-weighted noise levels of over 100 dB mainly from the impact of the nails against the steel spiral and collation boxes.
The solution
The solution was to enclose the entire feed system. Another idea - to use alternative materials for the collation boxes, and so remove the metal-on-metal impact - was rejected because it would have led to unacceptable wear and the loss of accuracy in the batching process.
The enclosure was manufactured from standard acoustic panels consisting of 30 mm and 50 mm thick mineral wool between a plain and a perforated steel sheet.
The product entered the enclosure along a chute that enabled nails to be poured from the adjacent washing machine into the feed system. The design included ample provision for access, including an ingenious arrangement on the corner where either portion of the door could be opened as required.
The main access was above the collation boxes where glazed panels were placed on hinges with handles for lifting clear. Other features of the enclosure included a ventilation fan on the roof to prevent overheating and the chamfering of one corner to allow operators to get closer to the equipment.
The cost
About £2500. (1995)
The result
A noise reduction of 26 dB.
Source
Photographs courtesy of Mato Industries Limited. Equipment designed and manufactured by Euro Acoustics Limited.