Sphygmomanometer sensitivity difference causes and methods of processing
The difference in sensitivity is reflected in the uniform pressure or buck, mercury column rise, slow down, there are beating phenomenon.
The main reason for the poor sensitivity is that the mercury oxide generated from oxidation in the mercury pollutes the pipe wall and hinders the sensitive lifting and lowering of the mercury column;
In addition, the ventilation hole at the upper end of the indicating tube is blocked and this kind of failure can also be caused. Resolve the method; repeatedly filter mercury, remove mercury oxide; clean the indicating tube; keep vents open.
Replace the leaky rubber ball, air tube or armband; equipped with the conical surface of the gas valve to improve the contact condition, increase the contact surface to improve the sealing performance or replace the gas valve; carefully insert the gas valve into the rubber ball;
Remove dirt from the slits on the valve rubber tube or replace it. When the sphygmomanometer indicates an unstable value, it must have a leak, but it is also more difficult to check the position of the leak.
Annoying, because the sphygmomanometer works when the pressure medium is air, the pressure is not high, but also pay attention not to overflow the mercury, a more feasible and simple way is to raise the pressure to 30kPa,
The body of the sphygmomanometer was immersed in clean water with a rubber ball, an air tube, and an armband. The water did not pass through the top of the mercury storage bottle, and the bubble was observed for repair.