The inclined blade of the VDI Inclined Slide Valve forms an eye-shaped aperture with the asymmetrically tapered inner body. The wider the eye is opened, the more material flows through, the further it is closed the more the material flow is reduced.
The inner body consists of a self-supporting SINT engineering polymer composite cast. The blade is manufactured from carbon or stainless steel. The valve can be operated manually, pneumatically or by electric gear motor. Intermediate blade positions instead of a complete opening are obtained through position sensors. To enforce material flow at low flow rates the dustproof VDI valve can be equipped with an additional pneumatic hammer that imparts repetitive percussions to the internal valve body during operation.