For water or low viscosity fluids, valves should be able to ensure that fluids are still circulating at low pressures, which is often referred to as the fluid characteristics of rubber valves supplied by gravity.
The viscosity of low viscosity fluids is similar to that of creams. Pressurized storage containers for supplying such fluids require degassing and agitation functions. Short tube valves and lifting valves with suction function are suitable for this fluid. Pneumatic needle valves are also available for medium viscosity fluids.
For high viscosity (500,000 cps) and corrosive materials with abrasive fillers, high strength pneumatic valves with corrosion resistance and wear resistance seals are suitable. The more abrasive the material is, the more frequent the maintenance cycle of the valve is.
When high viscosity fluid such as gel or silica gel needs precision, the container is usually 0.1 gallons or 1 to 5 gallons of barrels. The viscous fluid in the gun barrel pushes the pressure plate through the pneumatic pump, and the glue is squeezed into the valve cavity through the high pressure pipe. The fluid characteristics of the rubber valve are different.
It is important to note that the pneumatic pressure cylinder produces a phenomenon called tunnel effect, in which the intermediate fluid can be extracted. This is especially evident if box packing is not designed for automatic dispensing.
31 type compound ejector dispensing valve
In addition to viscosity, we must also consider the thixotropic properties of some fluids, which are one of the characteristics of rubber valve fluids. Fluids with thixotropic properties are difficult to pour, but after stirring, these fluids become creamy and easy to pour. Tomato paste is a good example. The requirements for fluids and gels with syrup consistency are the same, except that these fluids are usually stored in small tanks that are not degassed. Therefore, we must consider how to pump the fluid from the tank to the dispensing valve to degasse it. The paste is more viscous and can be sucked directly into the rubber valve from the packaged container.
Automatic dispensing valve for anaerobic glue
3. Erosive fluids
Pinch valves are usually used for acids and all solvent-based materials, because polyethylene pipes are disposable. Clamp valves have no corrosive wet chamber. Adhesive fluids, such as cyanoacrylate, are solvent-based adhesives and are highly corrosive, so if diaphragm valves are used, the wet chamber and piston and O-ring materials must be ultra-high molecular weight materials. Grinding fillers are usually pasty, which can enhance the electrical and dielectric properties of materials. Not all fillers are abrasive, so it is not necessary to have the manufacturer or supplier confirm the specific product performance in order to avoid expensive purchase of expensive dispensing valves. However, if it is determined that the fluid is abrasive, a dispensing valve should be used.