For measuring the gland packing size the following methods can be used.Take the reference of the old removed packing and cut accordingly.Put the new gland packing on the shaft circumferentially or on a template and then mark and then cut the required length.

　　The most accurate is to measure the size of the shaft and calculate its perimeter or circumference. For example if the shaft is of 50 millimeters diameter then the circumference is given by the formula P = Pi x Diameter. That would make the perimeter 157.07 millimeters. This measured length can be cut from the gland packing reel considering a 2 mm clearance in packing which would swell in presence of sea water.