Proportional valves PV and PVN are designed for proportional loading of regrind materials together with the main one in a certain proportion.

Proportional valves are used together with vacuum loaders, the control is carried out from the control panel of the vacuum loader. If a vacuum loader is used that does not have this function, then the control is carried out by the timer, by setting the loading time of each component, the timer is not included in the basic version of the proportional valve and is available separately on request.

The principle of operation is based on the proportional pneumatic valve is switched by an external source of compressed air, wherein one of the loading channels are always open and the second closed.

The advantages of proportional valves include the ability to load two different materials with a different fluidity and bulk density, for example a crushed material with granules, using a single vacuum feeder.

When using proportional valves, it is not necessary to install a separate dispenser for regrind materials.

Proportional dosing can be carried out with proportions of 30/70, 60/40, etc., while accurate dosing is not available with a 1-2% succession, and a small amount of added material, as a rule, the minimum amount of additive is 10-20% of total amount of plastic regrind material loaded by the loader.