Overview: The document is a technical data sheet for VECOBLOC® stationary variable pitch pulleys, primarily used in the fan industry. These pulleys enable the adjustment of fan speed by altering the pulley diameter.

Adjustment Procedure: The pulley diameter can be adjusted when stationary by moving the adjustable flange with a jacking screw. A 1.25 mm movement of the flange results in a 4 mm diameter change. Once the desired diameter is achieved, the mobile flange should be locked with a screw to prevent loosening.

Features of Pulleys: The document lists various pulley references with specifications such as diameter and weight for both 1-groove and 2-groove types. For example, the reference 11 has a diameter of 124 mm and a weight of 1.41 kg for a 1-groove pulley.

Diameter Specifications: The document provides possible original diameters according to the belt section used, with minimum and maximum diameters specified for different references and belt types (Z, SPZ, A, SPA, B, SPB).