1. Before using the pressure gauge, the pressure gauge pointer starts from zero. Firstly, explain a special situation. For some pressure gauges with lower range but larger outer diameter, the above situation only occurs when placed flat. However, when the pressure gauge is vertical, the pointer returns to zero. In this case, the pressure gauge pointer cannot start from zero and should be considered a qualified product.

2. Negligence and non-standard operations during the production process. Let's talk about assembly first. During the assembly process, some screws for installing accessories were not tightened. During the logistics transportation process, strong vibrations or human damage can cause the above-mentioned situations. For example, if the upper and lower compartments, dial, movement, and connectors of the movement are not tightened properly, it may cause the pressure gauge pointer to zero during transportation.

3. When checking the pressure gauge, the needle is not secure. Similarly, during logistics transportation, stainless steel pressure gauge pointers may not return to zero due to long, bumpy roads or some human factors.

If the pressure gauge is normal in the hands of consumers, what aspects should be paid attention to during use?

1. On site use is the touchstone for checking the quality of pressure gauges. Due to the diversity and complexity of the work environment, it is impossible to withstand severe vibrations during use, even though pressure gauges have a limit value. However, if the screws of the pressure gauge are not tightened properly before leaving the factory, it can cause the rod to loosen, the dial to be misaligned, and the movement to move, all of which can directly cause the pressure gauge pointer to start from zero.

2. Improper operation by the user, excessive pressure exceeding the limit of the pressure gauge range or even twice, can cause deformation of the spring tube, non elastic deformation, or detachment of the movement teeth. As the saying goes, "the pressure gauge is hit", but in fact, the pressure gauge pointer does not return to zero due to excessive pressure applied by the user during operation.

3. Due to the continuous force generated by the elasticity of the spring tube in the pressure gauge, even if operated properly, the pressure gauge pointer may still deviate from zero after a long period of use. This situation generally occurs in pressure gauges with a large range above 10MPa.