DYM1Moving trough mercury pressure gaugeHow to install:

The moving trough mercury pressure gauge should be installed in a pressure chamber with low temperature variation and sufficient light. For stations without a pressure chamber, it can be placed in a specially designed protective box. The pressure gauge should be securely and vertically suspended on walls, cement columns, or sturdy wooden columns, and should not be placed next to heat sources (heating pipes, stoves), doors and windows, or in places directly exposed to sunlight. No debris shall be piled up inside the pressure chamber. Before installation, the hanging plate or protective box should be firmly fixed in the place where the pressure gauge is to be hung. Carefully remove the pressure gauge from the wooden box (leather cover), with the groove facing upwards, and slightly tighten the groove bottom adjustment screw1--2Circle, slowly reverse the pressure gauge to make it stand upright with the groove below. Then insert the lower end of the slot into the fixing ring of the hanging plate, and then fit the top suspension ring of the gauge into the hook to make the pressure gauge naturally vertical. Slowly tighten the three screws on the fixing ring (be careful not to change the natural vertical state of the pressure gauge) to fix the pressure gauge. Rotate the bottom of the slot to adjust the spiral, so that the mercury level in the slot drops to the level of an elephantyaStop at the slightly lower position of the needle tip. Stable after installation3It takes an hour to observe and use.

DYM1How to use a moving trough mercury pressure gaugeObservation and recording:

1Observation of Auxiliary Temperature Gauge (abbreviated as“Temperature gauge”）Read to0.1℃When the temperature is below the lowest scale of the thermometer, another thermometer with a lower scale should be hung on the outer sleeve wall of the pressure gauge as the thermometer for reading.

2Adjust the mercury level in the mercury tank to match the imageyaThe needle tips are precisely in contact. When adjusting, rotate the bottom of the groove to adjust the spiral, so that the mercury level in the groove rises from bottom to top, and the action should be light and slow until it reaches the targetyaThe needle tip is precisely in contact with the mercury surface (there are no small eddies or gaps on the mercury surface). If small eddies occur, adjustments must be made again until the requirements are met.

3Adjust the ruler and reading. First, make the ruler slightly higher than the top of the mercury column, and align the line of sight with the front and back of the ruler ring on the same horizontal line. Then slowly lower the ruler until the front and back lower edges of the ruler ring are just tangent to the convex vertex of the mercury column. At this point, the integer can be read from the scale of the ruler indicated by the zero line at the lower edge of the ruler. Then find a scale line on the ruler that matches a certain scale on the ruler, and the number on this scale line on the ruler is the decimal reading.

4After retesting the readings, lower the silver surface. Adjust the spiral at the bottom of the rotating groove to make the mercury surface move away from the imageyaNeedle tip approximately2---3Millimeters. If there is insufficient light during observation, a flashlight or an electric light with a light shield can be used（1540Watt lighting. When lighting, the light should illuminate the white magnetic plate of the pressure gauge hanging board from behind the side of the pressure gauge, rather than directly shining on the top of the mercury column or the elephantyaPin it up to avoid affecting the accuracy of the adjustment.

5The pressure gauge must be hung vertically and regularly calibrated with a plumb line at two perpendicular positions.2When the convex surface of the mercury column on the barometer suddenly flattens and no longer recovers, or when its reading is significantly abnormal, it should be reported to the higher-level business department for handling.