Global Processing

A sweet savings

February 17, 2005
During the handling of fine or cohesive materials in a processing and packing line, a major cause of leakage or spillage of material are both slide valves and butterfly valves. This is a result of them jamming in operation thus preventing shut off of product flow and causing containers to be over-filled. The function of the blade of a slide valve passing through the material flow is the main cause of it failing. As the blade passes through the product, material is carried by the blade and backs up product into the runners or slide guides of the valve. This material then continues to accumulate until eventually the valve can no longer close.

A large confectionary manufacturer of lollypops experienced a typical example of this.

Intermediate bulk containers fitted with inadequate slide valves were being used to discharge confection ingredients into discharge chutes from an upper level in the factory, to lollipop presses and packing machines on a lower level. Because the slide valves were clogged with product, they would not close effectively and therefore led to leakage of product. This left piles of material surrounding the inlet holes to the discharge chutes, not to mention the occasional trail of powder leading up to these.

The level of waste due to this overspill caused by the inefficient slide valves was between 10% and 15% every year. When quantified in terms of lost revenue this represented approximately $300,000 per year, a significant amount of waste, totally unacceptable to the company’s senior management.

Kemutec was approached to solve the problem. There was no hesitation in deducing that the solution to the problem was The MUCON Iris Diaphragm Valve.

The principle of operation of the valve is a flexible tube of material that is fixed rigidly at each end. This tube is held in a mechanism that rotates through 180 ° . When twisted, the tube closes completely; creating a diaphragm that visually resembles that of a camera iris. This method of operation allows concentric closure of the iris and hence a high degree of flow control. No mechanical parts of the valve are in contact with the product as the diaphragm isolates these and as a consequence, there is no jamming of the valve.

The company has now equipped over 100 IBC’s with low cost Mucon Series H 150mm (6”) Iris Diaphragm Valves fitted with white food grade rubber diaphragms. As a result of the change, the company’s process has become cleaner and more efficient.

For further information contact Mucon, a division of Kemutec Group Inc., at 215-788-8013 or go to