A local sand foundry producing aluminium castings have been using Pinch Valves from AKO UK for 30+ years.
The company specialise in complex shapes and patterns within their sand casting and can produce a wide range of production sizes, from small intricate parts to pieces 2.5 metres in diameter.
The involvement of AKO Pinch Valves within this process is key. The valves control filling hoppers above 2 moulding tracks, shutting off and isolating the foundry sand with precision. The temperature of the sand is ambient, and it travels through the pipelines and pinch valves at 2-3 bar.
VF model, air operated, aluminium body, aluminium PN10/16 flanges with mild steel bushings, natural rubber sleeve.
VMC model, air operated, stainless steel body, Natural rubber sleeve, stainless steel PN10/16 flange connections.
Each valve controls the flow to alternative hoppers and are installed past a sand pump. One valve is normally open, and the other is normally closed. Approximately 80 to 100 cycles are performed per day when the plant is in operation. An amount of 5.5 bar air pressure is applied to the pinch valves to fully shut them off. (AKO valves have a differential pressure of 2-2.5 bar above the line pressure to close).
It is not known why the foundry are using one pinch valve in aluminium and the other in stainless steel. The valves for foundry sand were already installed when the technical manager we spoke to started working for the company, but aluminium would suffice for both lines.
Sand, although fine grade, is obviously abrasive but the natural rubber abrasion resistant sleeve which opens and closes to control the flow inside the pinch valve is very durable. The plant engineer on this plant who kindly spoke to us explained that AKO Pinch Valves for foundry sand are “fit for purpose”. The company have had such a long, reliable experience with pinch valves that they do not intend on using any other types of valves around this plant.
The rubber sleeve inside each valve is replaced when required, approximately every 2 to 3 years. Solenoids and pressure switches are also used in conjunction with the pinch valves.
