Oli Vibrators , leading supplier of quality vibrating equipment and flow aids, discusses the nature and benefits of material flow control technology.
The flow of bulksolid materials may be controlled with the aid of devices, mostly valves, designed for controlling the rate or stopping the flow, usually at the discharge section of a silo, hopper or pneumatic transport line.
The nature of the bulk solid material, especially such features as abrasiveness, corrosiveness, contaminability, degradability and temperature, apart from influencing the choice of material to be used for constructing the controlling device, or the need to carry out surface treatment on the parts which come into contact with the product and/or subject to wear, in some cases, strongly influences the type of valves to be used. It must be remembered that:
- The specific weight influences the pressure generated on the plug element and therefore on the torque to be transmitted to the actuators.
- The low flowability of cohesive powders determines the use of sections with larger passage.
- Abrasiveness orients the selection towards systems which do not concern the flow, to avoid maximisation of effects of abrasion, and prefers systems which allow product unloading to systems which trap the material in mechanical couplings (e.g. ball valve).
- In the case of fragile products, the systems selected must have limited cutting action (e.g. slide, butterfly valves).