Scribed line measured ruler, coarser ruler for scribed line thinner feet as a standard steel tape. Measured '1 m for measurement point, namely the checked steel tape in value or nominal value of 1 m. Reference value to determine the custom tailor tape measurement point, after reading method is: first, read distance measurement point near the standard steel tape whole rice point as the reference value of whole rice point (in m), then, plus or minus the standard steel tape by gauging survey points between the whole rice point distance value (in mm). When standard steel tape did not reach the whole rice point gauge measurement point, the reference value of whole rice and distance by gauging points between numerical values; When standard steel tape the whole rice point more than is gauging measurement point, the reference value of whole rice point minus the distance by gauging points between numerical values. Figure 1 so read reference value (or values) for 1 m + 0.6 mm, and according to the definition of error, figure 1 checked steel tape for error value of error = checked steel tape - reference value for value = 1 m - 0.6 mm (m + 1) = 0.6 mm. Steel tape test
Standard steel tape and checked steel bespoken tape measure tape should be parallel to install, and keep in the same plane. Standard steel tape and checked steel tape after the tension of each regulation, using zero institutions will be gauging the zero line of * heart and the zero line of standard steel tape * heart alignment. JJG4-2015 "steel tape verification regulations" in specific provision, verification Ⅰ steel tape and sounding steel tape, the turbulent deviation should be 0.01 mm reading microscope readings, standard steel tape and revised. Regulations in the "verification Ⅱ grade steel tape and subsequent verification of steel tape, standard steel tape without revised, the turbulent perception for deviation in reading." Rules of this sentence, the drafting team yi qing, jia-li liu published in the July 2016 issue of the journal of China metrology "JJG4-2015" steel tape verification regulation "interpretation" is known, should be understood as "Ⅱ grade steel tape follow-up verification can use standard steel tape when nominal value directly measured, class II steel tape first * calibration, standard steel tape should be revised to use."
Product introduction
1, PI ruler is composed of a high precision bespoken tape measure flexible steel band, (in order to meet the needs of customers we now with stainless steel and spring steel two kinds of materials) on both ends respectively inscribed with the foot line and pay scale line. Main ruler line scale value is 0.5 mm, pay scale line scale value is 0.02 mm.
2, using vernier reading principle, through the circumference measurement, direct reading round the average diameter of value, its precision is higher than the vernier caliper, and the larger the diameter value for the higher precision.
3, due to the steel band, thin, small, internal stress when measuring steel, reading is not affected by changes in temperature, stable precision, long service life.
4, stainless steel materials manufacturing PI feet, conform to the standard ISO3126-1974 plastic tubing - size measurement and GB/T8806-1988 plastic tubing size measurement method.