How to install the pressure gauge

The installation position of the pressure gauge should meet the requirements of the installation state. The dial should generally be in a vertical state. The position should be suitable for the staff to observe, and at the same time ensure the tightness and no leakage.

The following issues should be noted during the installation process:

(1) Selection of the position of the pressure port: First, make the sampling tube and the flow direction of the medium perpendicular to each other, and avoid the place where the valve, the fork and the elbow are easy to form a vortex; the second is to take the pressure when there is a protruding object in the pipeline. The mouth should be taken in front of it; the third is to measure the pressure of liquid and water vapor, the pressure point should be set on the lower side of the horizontal pipe, so that there is no gas in the pressure pipe, to avoid the sediment in the pipe blocking the sampling nozzle; It is a pressure gauge for measuring liquid and vapor media. * It is installed in the lower part of the instrument panel to prevent liquid or condensation from falling onto other instruments.

(2) Laying of the impulse tube: The pressure tube is used to transmit the pressure signal between the pressure point and the pressure gauge. The laying of the pressure tube should be noted. First, the inner diameter of the pressure tube is usually 6~10mm and the length is less than 50mm. Small measurement error and avoiding the lag of the medium cause the indication delay of the pressure gauge; secondly, the horizontal section of the connecting conduit should have a certain inclination, and the inclination should be maintained from 1:10 to 1:20 to facilitate the discharge of condensate or gas in the tube. The third is to install an isolation valve on the pressure piping to use when checking the pressure gauge.

(3) Determination of the installation height: the installation height should be suitable for the staff to observe, and the line of sight of the average person, that is, 1.5m ~ 1.6m, for high pressure should be higher than the average person's head, that is, about 1.7m ~ 1.8m. When the installation position of the pressure gauge is perpendicular to the position of the pressure measurement point, the correction of the liquid column difference should be performed. Correct the value of the pressure generated by the liquid column in the conduit equal to the vertical height difference between the meter and the pressure point. This correction value is added when the meter is above the pressure measurement point; otherwise, when the meter is below the pressure measurement point, this value should be subtracted.

(4) Use of sealing gasket: In order to ensure the sealing, the sealing gasket between the joint of the pressure gauge and the table should be selected with a suitable gasket. Use skin gasket or rubber gasket when working temperature and pressure is lower than 80 °C and 2MPa; use asbestos paper or aluminum pad at 80 °C ~ 45 °C, below 5MPa; use annealed copper pad or when working temperature and pressure are higher Lead pad.

The de-grater is used to treat the weighted drilling fluid, but a large-sized sand remover with a separation particle size greater than 74 μm must be used. Since the ratio of the sinker diameter of the barite to the drill cuttings is about 1:1.5, the sand remover capable of removing the drill cutting particles of 74 μm or more can also remove the barite powder of 49 μm or more. This part of the particles in the barite accounts for about 10%-15%. The weighted drilling fluid pretreated by the sand remover can then be used to reduce the burden of the mud cleaner. The disadvantage is that some of the barite with larger grain size suffers some loss.