Four elements of geometric quantity measurement

Any complete measurement process includes four aspects: the object to be measured, the unit of measurement, the measurement method, and the measurement accuracy. They are generally referred to as the four elements of the measurement process. The structural characteristics and measurement requirements of the measured object largely determine the measurement method. The measurement method refers to the combination of the measuring instruments and the measurement conditions used in the measurement. Measurement accuracy refers to the degree to which the measurement results are consistent with their true values.
Objects to be tested: including length, angle, shape, relative position and surface roughness. For the part to be tested, the influence of its size, weight, batch size, accuracy requirements, shape complexity and materials on the measurement should be considered.
Unit of measurement: refers to the standard quantity used to quantify the same type of value. In the legal measurement unit promulgated by China, the basic unit of the length of the geometric quantity is m (M), and the angle unit of the plane angle is rad and degrees, minutes and seconds. Millimeter is often used as a unit of measurement in mechanical manufacturing, and micrometers (um) or even nanometers are used for precision measurement.
Measurement method: The measurement method refers to the measurement principle and actual operation in actual measurement according to the given measurement principle to obtain measurement data and measurement results.
Measurement accuracy: refers to the degree to which the measured geometric quantity is consistent with its true value. In the process of measurement, due to various factors, measurement errors of large or small are inevitably generated. When the measurement error is small, the measurement accuracy is high, and the measurement error is large, and the measurement accuracy is low.

Roller Shutter Door

Roller shutter door , also known as "shutter door", lots of panel pieces connected together, fixed in the guide rail , take above reel as the center of rotation.


Roller shutter door is used for commercial facades, garages, shopping malls, hospitals, factories and mines and other public places or residential.Electric roller shutter door, especially for large openings, inconvenient to install the ground door , quick opening effect. Such as for the garage door, shopping mall fire shutter door.


Opening methods: Handing driving mode

Rope driving mode

Remote control driving mode

Electric switch driving mode

Roller Shutter Door,Galvanized Roller Shutter Door,Aluminum Roller Shutter Door,Transparent Roller Shutter Door

Shenzhen Hongfa Automatic Door Co., Ltd. , https://www.hfhighspeeddoor.com