Machinery shaft alignment calculator

A process for determining angular alignment positioning information for effecting alignment of coupled drive and driven units interconnected by coupling structure, comprising:

• providing an alignment calculator circular slide rule device, including:
• a lower disc comprising indicia circumferentially arranged thereon denoting shim dimensional characteristics for angular alignment of the drive and driven units by shim adjustment on support points of the drive unit selected from the group consisting of front and rear support points;
• an upper disc coaxially coupled to the lower disc, including an inner ring portion having circumferentially arranged thereon indicia denoting diameter of the coupling structure and an outer ring portion having circumferentially arranged thereon indicia denoting gap offset values, the upper disc including an annular window portion permitting viewing of the lower disc indicia when the upper and lower discs are coaxially coupled to one another;
• an index arm having an inner end portion which is coaxially coupled to the coaxially coupled upper and lower discs;
• a coupling member coaxially interconnecting the index arm, upper disc and lower disc, permitting independent rotational motion of each of same relative to the others;
• determining the linear distance between front and rear support points on the drive unit;
• setting the coupling diameter value from the coupling diameter indicia of the upper disc by angular movement of the upper and lower discs relative to one another, so that said linear distance between drive unit front and rear support points is located on the indicia of the lower disc and registered with the coupling structure diameter on the inner ring portion of the upper disc;
• measuring the angular alignment between coupling members of the drive and driven units to yield a measured gap offset;
• positioning the index arm of the alignment calculator circular slide rule device to the measured gap offset value on the outer ring portion of the upper disc, while maintaining the upper and lower discs in their prior position relative to one another, and reading the required shim size for said angular alignment on the indicia of the lower disc, between the inner and outer ring portions of the upper disc, as aligned with the index arm;
• and
• modifying the shimmed character of the drive unit support points with shims of the calculated size determined from the alignment calculator circular slide rule device.