The steel tape measure is a tool that we use and use more in our daily life. This tool is mainly used to measure distances. When we customize home furniture, we generally use a steel tape measure to measure the size, which can avoid errors between the customized wardrobe and the actual size that can be placed. How is the accuracy level of the steel tape measure calculated? Next, let's learn about the accuracy level of the steel tape measure and the main purpose of the steel tape measure. If you don't understand, you can refer to the accuracy level of the steel tape measure.


1. The accuracy grade of steel tape measure
The complete is Δ=±[(0.3+0.2L)+0.2] mm, where: L is the length value in m, when the length is not an integer multiple of m, take the nearest larger integer multiple. Δ=(0.3+0.2L)mm is grade II. For example, when the measured length is 30.2mm, take L=1 [Class I Δ=(0.1+0.1L)mm], Δ=0.065mm; when the measured length is 198.7cm, take L=2 [Class II], then Δ=0.08mm. It means the indication error limit from the zero point to any line.

2. Distance measurement
Generally, measure n full-foot sections first, mark them with measuring drills or scribes on the ground, and finally measure the excess length. The total length is: nX ruler section length + excess length In order to prevent errors in the measurement and improve the measurement accuracy, it is necessary to measure back and forth. . The difference between the measured length and the back measured length, divided by the approximate value of the length, is converted into a fraction with a numerator of 1, which is called relative error, or relative accuracy. The relative accuracy of the gauge distance should generally not be less than 1/3000. Between the two end points of the scale field is the standard length L, which is measured with the identified steel ruler, and L’ is obtained by temperature correction, (L-L’)/L is the correction per meter. Multiply by the nominal length to get the corrected value

3. Length correction of steel tape measure distance
(1) When the correction value of the foot length is greater than 1/10000 of the foot length, the foot length should be corrected;
(2) When the difference between the temperature and the standard temperature is plus or minus 10 degrees, the temperature correction should be added;
(3) When the ground slope measured along the ground is greater than 1.5%, the height difference should be added for correction.