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The flow meter installation is more attention-oriented and will not make mistakes after reading.

Precautions before installation

1. Before the flowmeter is installed, the process pipeline should be purged to prevent the ferromagnetic substances retained in the pipeline from adhering to the instrument, affecting the performance of the instrument and even damaging the instrument. If it is unavoidable, a magnetic filter should be installed at the entrance of the meter. The meter itself does not participate in the air sweep before the production, so as not to damage the meter.

2. Before installing the flowmeter into the process pipeline, check whether it is damaged or not and open the casing to remove the filler of the fixed pointer.

3. The installation form of the flowmeter is divided into vertical installation and horizontal installation. If it is vertical installation, the angle between the center vertical line and the plumb line should be less than 2°; if it is horizontal installation, the horizontal centerline of the instrument should be ensured. The angle with the horizontal line is less than 2°.

4. The upstream and downstream pipelines of the flowmeter should be the same as the gauge of the instrument. The connecting flange or thread should be matched with the flange and thread of the instrument. The length of the straight pipe upstream of the instrument should be 5 times of the nominal diameter of the instrument, and the length of the downstream straight pipe segment is greater than Equal to 250mm.

5. Since the flowmeter transmits signals through magnetic coupling, in order to ensure the performance of the instrument, at least 10 cm around the installation, no ferromagnetic substances are allowed.

6. The flow meter for measuring gas is calibrated at a specific pressure. If the gas is directly discharged to the atmosphere at the outlet of the meter, a pressure drop will occur at the float and cause data distortion. If this is the case, install a valve at the outlet of the meter.

7. The flowmeter installed in the pipeline should not be subjected to stress. The inlet and outlet of the instrument should have proper pipeline support, which can make the instrument in minimum stress state.

8. Be careful when installing PTFE (polytetrafluoroethylene)-lined instruments. Since the PTFE will deform under the action of pressure, the flange nut should not be over tightened at will.

9, with a liquid crystal display instrument, when installing, try to avoid direct sunlight display, reduce the life of the LCD.

10, when measuring low temperature media, you need to choose the jacket type.

Precautions during installation

1. The flowmeter opening should avoid opening holes in the forming pipe.

2. Pay attention to the length of the straight pipe before and after the flowmeter.

3. If there are electromagnetic, quality and other flowmeters with grounding requirements, grounding should be carried out according to the instructions.

4. When welding the process pipeline, the grounding wire should avoid the instrument body to prevent the grounding current from flowing into the ground through the instrument body and damaging the instrument.

5. When welding the process, avoid the grounding current flowing through the capillary pressure guiding tube of the single and double flanged instruments.

6, medium and high pressure impulse pipe can be used for argon arc welding or socket welding, should use argon arc welding or socket welding. Wind speed > 2m / s, there should be wind-proof measures, otherwise the coating wire should be used, wind speed > 8m / s, must have wind-proof measures, otherwise the welding should be stopped.

7. Pay attention to the installation direction of the flow port of the flowmeter throttling device.

8. Stainless steel pressure pipe is strictly prohibited; it is strictly forbidden to flatten the pressure pipe.

9. The installation position of the instrument's impulse piping, air duct and threading pipe should avoid obstructing the process production operation in the future. It should avoid the high temperature corrosion place and should be fixed firmly; the lowest lead end of the threading pipe from the upper side should be lower than the lower lead end. The wiring inlet end of the connected instrument; the lowest end of the threading pipe should be added with a drip tee; the Y-type or tapered explosion-proof sealing joint should be added near the instrument side; the lowest point of the main wind line of the instrument should be a condensing (soil) valve.

10. The copper gasket used in the flowmeter, if it is not annealed, should be annealed before use, and pay attention to the allowable temperature, medium and pressure conditions of various material gaskets.

11. In the field instrument junction box, the grounding of different grounding systems cannot be mixed. The shielding wires of all instruments should be connected separately to the upper and lower shielding layers. It is forbidden to screw them together to connect the upper and lower shields.

12. When the flowmeter is in a position where it is difficult to observe and repair, report to Party A to agree to change the position or install the platform.

13. The joint is strictly prohibited in the middle of the flow meter line. If there is any special situation, the party A agrees and the hidden record is made. The compensation wire joint should be welded or crimped.

14. Stainless steel welding joints should be pickled, passivated and neutralized.

15. Instruments and fittings that need to be degreased should be degreased in strict accordance with the specifications, and the sealing and storage work of the instruments and fittings after degreasing should be carried out to prevent secondary pollution during storage and installation.

16. Stainless steel pipelines are strictly prohibited from direct contact with carbon steel.

17, galvanized, aluminum alloy cable tray is strictly prohibited to use electricity, gas welding cutting and opening, should use non-tooth saw and special hole opener and other similar mechanical cutting and opening.

18, stainless steel pipe is strictly prohibited to use electricity, gas welding cutting and opening, should be plasma or mechanical cutting, opening.

19, instrument threading pipe, cabinet, disk, etc. larger than 36V should be grounded, grounding instrument threading pipe thread with conductive paste treatment; less than or equal to 36V instrument threading pipe thread should at least have anti-rust treatment; exposed thread should not be larger than one wire buckle.

20. The instrument threading pipe in the explosion hazardous area shall maintain electrical continuity.

21, 100 volts or less insulated instrumentation line using 250V shaker to measure the line insulation resistance, and ≥ 5 megohms.

22, aluminum alloy bridge should be short-circuited across the bridge, galvanized bridge should be no less than two anti-loose screws, the length should be reliably grounded within 30 meters, more than 30 meters should be added a grounding point every 30 meters.

23. When the instrument line or instrument line of different grounding systems shares a slot with the power line, they are separated by a metal partition.

24. It is strictly forbidden to use the gas welding method in the installation and processing of instrument panels, cabinets, boxes and tables. The welding method should not be used for the installation and fixing, and the mechanical opening method should be adopted for the opening.

25. The blind end of the instrument with heat and return water should not exceed 100mm.

26, the lower mouth of the transmitter sewage valve should increase the leakage of the valve cap (especially in the explosion-proof area).

27. The flowmeter, its threading pipe and the pressure guiding pipe are fixed at one end in the thermal expansion zone (such as the tower, the accessory that moves with the thermal expansion of the tower), and one end is fixed in the non-thermal expansion zone (such as labor protection room). When connecting the instrument, it should be based on the actual situation of the site. The flexible pipe, the threading pipe and the pressure pipe must have a certain thermal expansion margin.

28. The tower bridge and the threading pipe shall be provided with thermal expansion joints or flexible joints according to the actual situation on site.

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