Circumferential tape measure with diameter scale, especially for direct measurement of pipe diameters, e.g. in pumping installations, has one side with a diameter scale where graduations represent lengths divided by pi

摘要

Circumferential tape measure has one side marked with markings representing the conversion calculation length (circumference) divided by pi so that, in addition to circumferences, diameters can be directly measured. Optimally the tape is flat so that it can easily be coiled around a pipe.