The main structure of the steel tape measure is a whole steel strip with certain elasticity, and the steel strip has the characteristics of thermal expansion and contraction.
(1) When the temperature of the standard steel tape and the tested steel tape are both 20%, the size error caused by the temperature is zero.
(2) When the standard steel tape measure and the tested steel tape measure have the same material and the same temperature, the dimensional error caused by the temperature is proportional to the thermal expansion coefficient and the temperature.
(3) When the standard steel tape measure and the tested steel tape measure have the same material and different temperatures, the size error caused by the temperature is proportional to the thermal expansion coefficient and the temperature difference between two feet.
(4) When the standard steel tape measure and the tested steel tape measure have different materials and the same temperature, the size error caused by the temperature is proportional to the difference in the thermal expansion coefficient of two feet and the temperature of two feet.
(5) When the standard steel tape measure and the tested steel tape measure have different materials and different temperatures, the size error caused by the temperature is proportional to the thermal expansion coefficient difference of two feet and the temperature difference of two feet.