To analyze and deal with two situations:
One is that the hysteresis for the new production stainless steel case is poor when they are adjusted. The main reason is that the elasticity of the spring tube is too late. The general treatment method is to perform 130% overpressure aging treatment on the meter, and the overpressure time is more than 30 minutes to increase the proportional limit of the spring tube and reduce its elastic delay.
The second is the use of a period of time overhaul of the pressure gauge, overhaul error occurs in the repair there are the following possibilities;
1. Due to the frequent operation of the instrument, the clearance at the joints of the parts is too large. For example, the looseness of the shaft and the hole, the excessive clearance of the shaft gap and the radial clearance, the wear of the teeth, and the looseness of the fitting may cause the return difference to be poor. This requires the identification of the location of the fault and the symptomatic solution.
2. Accumulation of dirt in the spring tube is also one of the reasons for the instrument to produce a backlash.
The treatment method is to use a medical injection needle to inject gasoline into the spring tube and oscillate and clean until the accumulated dirt is clean.
3. The deformation of the spring tube is one of the main reasons for the back and forth difference of the instrument.
If the meter's back and forth difference is large and appears at the same time as it does not return to zero, it can be assumed that the spring tube has been deformed. Deformation of the spring tube cannot be repaired. Replace the spring tube (joint part) or the obsolete instrument.
