Ten precautions before installation oforifice flowmeter
1. Before the instrument is installed, theprocess pipeline should be purged to prevent the ferromagnetic substancesretained in the pipeline from adhering to the instrument, affecting theperformance of the instrument and even damaging the instrument. If it isunavoidable, a magnetic filter should be installed at the entrance of themeter. The meter itself does not participate in the air sweep before theproduction, so as not to damage the meter.
2. The instrument should be inspected fordamage before it is installed in the process piping.
3. The installation form of the instrumentis divided into vertical installation and horizontal installation. If it isvertical installation, the angle between the center vertical line and thevertical line of the instrument should be less than 2°; if it is horizontalinstallation, the horizontal center line of the instrument should be thehorizontal line angle is less than 2°.
4. The upstream and downstream pipelines ofthe instrument shall be the same as the diameter of the instrument. Theconnecting flange or thread shall be matched with the flange and thread of theinstrument. The length of the straight pipe upstream of the instrument shall beat least 5 times the nominal diameter of the instrument, and the length of thedownstream straight pipe segment shall be greater than equal to 250mm.
5. Since the instrument transmits signalsthrough magnetic coupling, in order to ensure the performance of theinstrument, at least 250px around the installation, no ferromagnetic substancesare allowed.
6. The instrument for measuring gas iscalibrated at a specific pressure. If the gas is directly discharged to theatmosphere at the outlet of the meter, a pressure drop will occur at the floatand cause data distortion. If this is the case, install a valve at the outletof the meter.
7. The instrument installed in the pipelineshould not be subjected to stress. The inlet and outlet of the instrumentshould have appropriate pipe support to keep the instrument under minimumstress.
8. be especially careful when installingPTFE (polytetrafluoroethylene)-lined instruments. Since the PTFE will deformunder the action of pressure, the flange nut should not be over tightened atwill.
9. The instrument with liquid crystaldisplay should avoid direct sunlight when installing, and reduce the servicelife of the liquid crystal.
10. When measuring low temperature media,you need to select the jacket type.
Twenty-eightprecautions in the installation process of orifice flowmeter
1. The opening of the meter should avoidopening holes in the forming pipe.
2. Pay attention to the length of thestraight pipe before and after the flowmeter.
3. If there are electromagnetic, qualityand other flowmeters with grounding requirements, grounding should be carriedout according to the instructions.
4. When the process pipeline is welded, thegrounding wire should avoid the instrument body to prevent the groundingcurrent from flowing into the ground through the instrument body and damage theinstrument.
5. When welding the process, avoid thegrounding current flowing through the capillary pressure guiding tube of thesingle and double flanged instruments.
6. The medium and high pressure impulsepipe can be argon arc welding or socket welding, and argon arc welding orsocket welding should be adopted. Wind speed > 2m / s, there should bewind-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 installationdirection of the flow port of the flowmeter throttling device.
8. Stainless steel pressure pipe isstrictly prohibited; it is strictly prohibited to flatten the pressure pipe.
9. The installation position of theinstrument’s impulse piping, air duct and threading pipe should avoid theprocess production operation in the future, should avoid the high temperaturecorrosion place, and should be fixed firmly; the lowest lead end of thethreading pipe from the upper side should be lower than the lower lead end Thewiring inlet end of the connected instrument; the lowest end of the threadingpipe should be added with a drip tee; the Y-type or tapered explosion-proofsealing joint should be added near the instrument side; the lowest point of themain wind line of the instrument should be a condensing (soil) valve.
10. The copper gasket used in theinstrument, if not annealed, should be annealed before use, and pay attentionto the allowable temperature, medium and pressure of various material gaskets.
Leaf dividing line
11. In the field instrument junction box,the grounding of different grounding systems cannot be mixed. The shieldingwires of all instruments should be connected separately to the upper and lowershielding layers. It is forbidden to screw them together to connect the upperand lower shielding.
12. When the instrument is in anunobservable and inspected position, change the position or install theplatform.
13. The joint is forbidden in the middle ofthe instrument line, and the hidden record is made. The compensation wire jointshould be welded or crimped.
14. Stainless steel welds should be pickled,passivated, and neutralized.
15. Instruments and fittings that need tobe degreased should be degreased in strict accordance with the specifications,and the sealing and storage of the instruments and fittings after degreasingshould be carried out to prevent secondary pollution during storage andinstallation.
16. Stainless steel pipelines are strictlyprohibited from direct contact with carbon steel.
17. Galvanized and aluminum alloy cabletrays are strictly prohibited from being cut and opened by electricity, gaswelding, and similar mechanical cutting and opening should be used withouttooth saws and special hole openers.
18. Stainless steel pipes are strictlyprohibited from being cut and opened by electricity or gas welding. Plasma ormechanical cutting or opening should be used.
19. Instrument threading pipes, cabinets,discs, etc. larger than 36V should be grounded, grounding instrument threadingpipe threading wire should be treated with conductive paste; instrumentthreading pipe thread buckle of 36V or less should have at least anti-rusttreatment; exposed thread buckle should not be larger than one wire buckle.
20. Instrument Threading Pipes in ExplosiveHazardous Areas shall maintain electrical continuity.
21.100 volts are measured using a 250Vshaker to measure the line insulation resistance and ≥ 5 MΩ.
22. The aluminum alloy bridge should beshort-circuited across the short-circuit. The galvanized bridge should betightened with not less than two anti-loose screws. The length should bereliably grounded within 30 meters. If it exceeds 30 meters, a grounding pointshould be added every 30 meters.
23. When the instrumentation line orinstrumentation line of different grounding systems shares a slot with thepower supply line, they are separated by a metal partition.
24. It is strictly forbidden to use the gaswelding method in the installation and processing of the instrument panel,cabinet, box and table. The welding method should not be used for the installationand fixing. The mechanical opening method should be adopted for the opening.
25. The blind end of the instrument forheating and returning water should not exceed 100mm.
26. The lower part of the transmitter drainvalve should be equipped with a cap that prevents leakage of the valve(especially in the explosion-proof area).
27. The instrument and its threading pipeand pressure pipe are fixed at one end in the thermal expansion zone (such asthe tower, the accessory moving with the thermal expansion of the tower), andone end is fixed in the non-thermal expansion zone (such as labor protectionroom). When connecting the instrument, it should be based on the actualsituation on site. The flexible pipe, the threading pipe and the pressure pipemust have a certain thermal expansion margin.
28. The tower bridge and the threading pipeshall be provided with thermal expansion expansion joints or flexibleconnections according to the actual situation on site.
Sichuan VacordaInstruments Manufacturing Co., Ltd
21 Years FocusedonLevel MeasurementinExtremeProcessConditions
Tel: +0086 28 8701 3699
Email: sales@vacorda.com
Web: www.vacorda.com
Post time: 21-09-21