Pressure gauge is a common measuring instrument, which is widely used in various fields. The "needle dropping" problem of pressure gauge is analyzed and solved.
Tips:
The needle drop of pressure gauge should be one of the most common failures among instrument failures. It is a problem that the pressure gauge has lost its most basic use function and is also a worry for the majority of users.
The "needle drop" of the pressure gauge can be divided into two situations: one is that the needle drop is found after the instrument arrives or before use; The second is that the pointer falls off when the instrument is in use.
Cause analysis:
The reasons for instrument needle dropping after arrival or before use are generally the following two aspects:
① After the instrument is adjusted, no pin or pin fishing is conducted;
② Improper handling of the instrument during transportation will cause the pointer to fall off due to large vibration.
The reasons for needle dropping of the instrument in use are generally as follows:
① After the instrument is calibrated, the pin is not nailed or the pin is not firm;
② The taper of the inner hole of the needle library is not consistent with the taper of the central shaft of the core, resulting in the loose pin;
③ The riveting between the needle magazine and the needle piece is not firm, and the needle piece or the needle magazine is separated due to vibration or impact;
④ The pressure of the pressure gauge is released too fast, and the pointer repeatedly and violently hit the disc stopper, causing it to fall off;
⑤ The working environment of the instrument has large amplitude and high frequency, and the pointer falls off due to long-time operation.
Improvement measures:
① Improve the sense of responsibility of factory staff
② Express and logistics
As for the problem of needle dropping, there are also many hidden dangers in logistics, such as bumps in the process of transportation, and personnel falling during handling
All are problems. In order to protect the interests of customers, we must also choose the most appropriate method to ensure the quality of our products and deliver it to every customer.
③ Find out the reason from whether the parts are qualified and tooling
If a large number of instruments are out of calibration for "needle dropping", the reason should be found from whether the parts are qualified, such as whether the taper of the central shaft of the core is qualified, and whether the taper of the hole miller in the needle library is consistent with the taper of the central shaft.
If the pressure gauge with reverse movement is installed, its movement plate is riveted on the street. When nailing, the movement plate has no back support and can't eat well, which is also one of the reasons that the pin is not firm. This needs to be solved by improving the tooling.
④ Add a check on pin strength
