Before verification the constant temperature time of keychain tape measure the ruler to be verified at the specified temperature shall not be less than 4ho (2) Verification items and tools of steel tape The verification items and verification tools of steel tape are listed in Table 1 3 Technical requirements and verification methods (1) Appearance and interaction of each part ① Requirements 1) The pulling out and winding of the steel tape shall be light and flexible without jamming and each functional device shall be able to effectively control the winding of the tape 2) Lay the tape on the verification table with specified tension The tape surface shall be free of unevenness and distortion Both edges of the tape shall be smooth and free of sharp edges and burrs from the mouth of the ruler box 6) The division value of ordinary steel tape is 1 ~ 5 ~ and 10 ~ and their line lengths shall be significantly different The division value of sounding steel tape and steel tape is 1 ~ Lines of the same personalized tape measure kind shall be of equal length 7) Within each decimeter (DM) the centimeter (cm) graduation line shall be marked with the numerical value in centimeter (cm) For a steel tape with a total length of less than sm the lines of the decimetre (DnL) and meter (m) divisions shall be marked with a value in centimeters (cm) from the zero line For a steel tape with a total length of more than sm the value in centimeter (cm) shall be marked within each meter (m) for the decimetre (DM) division line and the value in meter (m) shall be marked one by one from the zero division line; the unit of m may not be marked after 10 m 8) The connection parts of the steel tape shall be firm and reliable and not easy to produce tensile de
The industrial grade steel tape in use is allowed to be degraded for use if it fails to meet the industrial grade requirements after verification ② Verification method 1) Verification method of zero error Lay the ordinary steel tape with hook or pull ring at the end of the tape on the steel tape verification table and compare it with the qualified standard steel tape after applying the specified tension mini tape measure Align the ruler hook (or pull ring) indicating the zero position with the zero line of the standard steel tape and read the error value at 100 ~ The zero error of the sounding steel tape is verified with a zero calibrator as shown in Figure 2 1 — baffle; 2 — V-shaped support; 3 — ruler; 4 — ruler belt; 5 — pulley; 6 — ruler First place the ruler of the tested deep steel tape on the V-shaped support of the zero calibrator make its front end face close to the zero position baffle of the zero calibrator and place the tape on the table of the calibrator along the axis of the ruler At this time read the zero error at the 500 mm line marked on the table of the calibrator 2) Verification method for indication error of steel tape at any section Use the qualified Class I standard steel tape on the steel tape verification table to compare and measure with the tested ruler (the friction between the steel tape verification table and the tested ruler shall be ≤ 4 N) Firstly the standard steel tape and the verified steel tape shall be fastened on the verification table by the compacting device and the tension shall be applied to the other end of the standard steel tape and the verified steel tape respectively as required Adjust the zero adjustment mechanism on the verification table to align the zero line of the verified ruler with that of the standard ruler (for the steel tape for depth measurement the line at 500 ~ is aligned with that of the standard steel tape) and continuously read the error of each section and the total length section by section per meter For the steel tape with a total length of less than 3m the inspected section shall not be less than 3 sections The indication error between any two lines shall be evaluated by selecting 2 to 3 sections within the full length range while being verified meter by meter and the indication error shall not exceed the allowable error of the corresponding section When the total length of the ruler to be verified is greater than the length of the verification table the sectional method can be used for verification and the total length error is the algebraic sum of the errors of each section
Electro-optical ranging belongs to indirect ranging 3 Distance measurement with tape measure Types of Tape Measures and Spacing Tools There are steel tapes and tape measures with lengths of 20 m 30 m and 50 m 4 Distance measurement Generally the whole length of n is measured first marked on the ground with a measuring drill or a line and finally the remaining length is measured The total length is NX ruler section length + surplus length In order to prevent errors in measurement and improve measurement accuracy round-trip measurement is required The difference between the forward measured length and the backward measured length divided by the probable 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 steel rule gauge shall generally not be less than 1/3000 The standard length L is between the two end points of the scale field which is measured by the identified steel ruler L 'is obtained by temperature correction and (L-L')/L is the correction per meter Multiplied by the nominal length the correction is obtained Length correction of steel tape gauge (1) When the correction value of ruler length is greater than 1/10000 of the ruler length the ruler length correction shall be increased; (2) When the difference between the temperature during span measurement and the standard temperature is plus or minus 10 degrees the temperature correction shall be added; (3) When the ground slope measured along the ground is greater than 15% the height difference correction shall be added Steel tape is the main type of tape which can be divided into self-rolling tape braking tape rocking tape and so on The use of steel tape is also relatively simple but attention should be paid to the operation improper operation or carelessness will be scratched Return to Sohu to see more Responsible Editor tape-measure.com
