What causes the pressure gauge pointer to deviate from zero | not return to zero?

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This post was last edited by Sales Support on 2017-8-8 at 11:03. It’s common to see questions online regarding the issue of pressure gauge pointers not returning to zero. In fact, this is one of the common faults associated with pressure gauges, and there are various reasons for it. Today we will give an overview of some of the more typical ones. After purchasing a pressure gauge, consumers usually open its packaging to check whether the pointer is pointing at zero; if it isn’t, that’s a sign of a problem. This indicates that the indicated value is inaccurate; consumers cannot accept such a situation, and a device with this problem must not be used under any circumstances. What are the reasons why the pressure gauge pointer does not return to zero? 1. Before using a pressure gauge, if its pointer is not at zero, there is a special situation to consider: in some pressure gauges with a low measurement range but a large outer diameter, this issue only occurs when the gauge is placed horizontally. When the gauge is held vertically, the pointer returns to zero, and this situation cannot be considered as the pointer being off from zero; such a gauge should still be regarded as a qualified product. 2. Carelessness and non-standard operations during the production process. Starting with assembly, in some cases the screws used to fix certain components are not tightened properly. Intense vibrations during transportation or physical damage can lead to such issues. For example, if the screws that hold together the upper and lower layers of the movement, the dial, the movement itself, and the connectors are not tightened properly, it is very likely that this will cause the gauge pointer to deviate from zero during transportation. 3. When calibrating a pressure gauge, the needle may not be secure; similarly, during logistics transportation, due to long distances, bumpy roads, or various human factors, it is possible for the gauge’s pointer to fail to return to zero. If the pressure gauge is in normal condition when it reaches the consumer, then what aspects should we pay attention to during its use? 1. Actual use in the field is the true test of a pressure gauge’s quality. Due to the diversity and complexity of working environments, intense vibrations can occur during use. Even pressure gauges have their limits and cannot withstand such severe vibrations. If the screws on a pressure gauge are not tightened properly before it leaves the factory, it can lead to loosening of the linkage rods, misalignment of the dial, and movement of the movement mechanism – all of which can cause the gauge pointer to deviate from zero. 2. If the user operates improperly, applying excessive pressure that exceeds the range limit of the pressure gauge or even doubles it, this can cause deformation of the spring tube (note: it is an inelastic deformation), or the teeth of the movement mechanism may come loose. In other words, it’s as if the pressure gauge has been damaged; in fact, the user applies too much pressure during operation, thereby damaging the pressure gauge and causing its pointer not to return to zero. 3. Due to the continuous force exerted by the elasticity of the spring tube in the pressure gauge, even if it is used properly, the gauge pointer may deviate from zero after prolonged use. This phenomenon is more common in pressure gauges with a large range, above 10 MPa. Therefore, as a precise pressure measuring device, a pressure gauge requires extreme care throughout its production, transportation, and use – no negligence is permitted. Only by adopting a responsible attitude toward production and following strict usage guidelines can each pressure gauge fulfill its maximum potential. This article is a reprint; the original title was: (Reasons why the pressure gauge pointer does not return to zero or stays away from zero).