The matter that electromagnetism flowmeter error makes

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  • source:DALLMAN CNC Machining
Electromagnetism flowmeter has a lot of advantages, dan Rexuan, installation, use undeserved, will cause an error to increase, indication is not stable, express body attaint even. 1, the solid body such as farinaceous, grain or fiber is contained in solid photograph liquid is being contained in the liquid, the breakdown that arises possibly has: Electrode surface profanes; size to noise; liner is worn away or be enclothed by deposit, current cut area narrows layer of deposit of layer of deposit of; electric conduction or insulation enclothes electrode or liner; . 2, because back pressure inadequacy or position of flow transducer installation are bad,the liquid inside the canal was full of, cause its to measure the liquid inside the canal to fail to be full of, because breakdown phenomenon is not full of degree and condition of going from place to place to have different show. If a few gas show minute of laminar flow or wave shape to flow in conduit conduit, breakdown phenomenon expression increases for the error, shed quantity measured value and real value to not agree with namely; is like flow is bleb flows or shape of a place of strategic importance flows, breakdown phenomenon nots agree with except measured value and real value outside, still meet appear because of surface of electrode of cover of gas phase instant output rock; if laminar flow of horizontal conduit cent moves midstream to connect part of cut area gas phase to increase, namely the liquid was not in charge of degree to increase completely, also can appear output rock, if the liquid is not full tubal case is more severe, face of fluid of as a result is under electrode, can appear be defeated by favorable balance of trade to spend a phenomenon completely. 3, if the problem liquid conductivity that liquid electrical conductivity exceeds limit to cause is close to floor level value to appear likely also rock phenomenon. Because manufactory appearance is normative (the floor level value that Specification) provides is better in all sorts of use condition the lowermost value that give can be measured below condition, and actual condition cannot be very ideal, encounter for many times then low spend distilled water or go ionic water, its conductivity is close to the lower limit that electromagnetism flowmeter standard sets to be worth μ S/cm, output rock appears however when using. Think to be able to stabilize value of metrical conductivity floor level to want normally tall 1 ～ 2 amounts class. 4, simple alternative of electrode and material of ground connection annulus is undeserved because material does not match with the medium that be measured character and caused problem causes the electromagnetism flowmeter of breakdown and the component that medium contacts to have electrode and ground connection link, match improper to divide anti-corrosive outside the problem, as long as it is electrode surface effect. Exterior effect is due: Electrochemistry and polarization phenomenon (generation electromotive force) ; catalysis (electrode surface generates gas mist to wait) ; chemistry reacts (the surface forms Zuo word film to wait for) . Ground connection annulus also has these effect, but influence degree wants a few smaller. 5, the liquid that crystallizes likely, it is normal below the circumstance with normal temperature that electromagnetism flowmeter Ying Shen uses stock of chemical industry of a little easy crystallization measure, because carry the conduit of the fluid to good companion heats up heat preservation, won't crystal when heat preservation works, but the measurement of electromagnetism flow transducer is in charge of carry out the heat preservation that accompany heat hard, accordingly, when the fluid has flowed to measure a canal go up easily because of drop in temperature and causing wall to written guarantee a solid. Because convert,the flowmeter of other principle is measured put in crystallization problem as much, fall in the circumstance that does not have other better method so, can choose measure a tubal length is very short kind " annular " (Oring) electromagnetism flow transducer, heat up the upriver conduit companion of flowmeter heat preservation to give aggrandizement. On pipeline link method, consideration flow transducer is torn open outfit is convenient, once next maintenance can be torn open conveniently when crystallization,be in. CNC Milling CNC Machining