A powder handling, processing & containment company who design, manufacture, supply and install machinery for materials in oral solid dosage (OSD) use AKO Pinch Valves on many of their bespoke systems.
Here, we look at a machine handling wood shavings for the manufacture of high end engineered laminate flooring by the end user.
The wood shavings in this particular application are ambient at approximately 21°C. There is no pressure of the wood shavings travelling through the pipelines within the machinery – it is sucked through the system using a degree of vacuum to meet a target of 2309 kg/hr.
There are two EX conformed AKO Pinch Valves installed in line with stainless steel pipe work on this system, which means they are certified for use in areas with a potentially explosive atmosphere
EX Conformed Pinch Valve, DN65, Natural Rubber conductive sleeve, stainless steel tri-clamp connections, aluminium body.
One pinch valve is normally open, and the other is normally closed. The two valves for wood shavings work in conjunction with one another by either opening or closing a desired path for the vacuumed product, to good or bad lines.
The system runs continuously with no breaks. The Pinch Valves are fully shut off at 3 bar.
To date, the end user is very satisfied with their system and keep one spare sleeve per valve for wood shavings on the shelf in case of an emergency failure or for scheduled maintenance.
The original equipment manuacturers who fitted AKO Pinch Valves to their machinery have been using pinch valves within their systems for 10+ years. They told us that they use other types of valves including ball valves, butterfly valves, knife gate valves, check valves and diaphragm valves on a daily basis, depending on the application.
They explained that AKO Pinch Valves are their preferred choice in many applications:
“Pinch Valves do not have a vane like a butterfly valve, therefore no bridging of product can occur. The Pinch Valve is a very good product.”
Controlled filling systems using butterfly valves are occasionally used on silo safety systems, but the flow through the valve is restricted by the butterfly disk, slowing down the filling process. The valve seat becomes contaminated with trapped product, resulting in spillage, waste and cross-contamination. The butterfly disk also wears very quickly increasing maintenance down time.
The use of a pinch valve eliminates these problems immediately. A full bore diameter allows unrestricted product flow. Tanker discharge time can be effectively reduced by more than 10%. FDA approved white rubber sleeves can be supplied with stainless steel contact parts for handling foodstuffs and pharmaceuticals.
Pinch Valves have been used for years in all abrasive applications. Due to the sleeve technology clear bore and simplicity of the pinch valve, the life in certain applications can be up to 6 times longer than a butterfly valve.
