Corrosion hi a thlentu pawimawh ber pakhat a nivalve a nitichhia. Chuvangin, invalve a nivenhimna, valve anti-corrosion hi ngaihtuah tur pawimawh tak a ni.
Valve a nicorrosion form a ni
Metal corrosion hi chemical corrosion leh electrochemical corrosion vang a ni ber a, non-metallic materials corrosion hi a tlangpuiin direct chemical leh physical action vang a ni.
1. Chemical hmanga thil tihchhiat (corrosion).
Current siam chhuah loh dinhmunah chuan a chhehvel medium chuan metal chu direct-in a inrem a, a tichhia a, chu chu high-temperature dry gas leh non-electrolytic solution-in metal a tihchhiat ang chi hi a ni.
2. Galvanic atanga chhuak (galvanic corrosion) a awm
Metal hi electrolyte nen an inzawm a, chu chuan electron a luang chhuak a, chu chuan electrochemical action hmangin a tichhia a, chu chu corrosion chi khat ber a ni.
Common acid-base salt solution corrosion, boruak a corrosion, leilung corrosion, tuifinriat tui corrosion, microbial corrosion, pitting corrosion leh stainless steel-a crevice corrosion, etc. te hi electrochemical corrosion vek an ni. Electrochemical corrosion hi chemical role nei thei thil pahnih inkara thleng mai ni lovin, solution concentration danglamna, a chhehvel oxygen concentration danglamna, thil awm dan inang lo tlemte, etc. avanga potential danglamna a siam a, corrosion power a hmu a, chutiang chuan metal potential hniam tak leh dry sun plate awmna chu a bo ta a ni.
Valve a hnim hrual zat
Corrosion rate hi grade parukah then theih a ni:
(1) Corrosion-resistant tak: corrosion rate chu kum khatah 0.001 mm aia tlem a ni
(2) Corrosion resistant nasa tak: corrosion rate 0.001 atanga 0.01 mm/kum khatah
(3) Corrosion resistance: kum khatah 0.01 atanga 0.1 mm inkar a ni
(4) Still corrosion resistant: kum khatah 0.1 atanga 1.0 mm inkar a ni
(5) Corrosion resistance tha lo: corrosion rate 1.0 atanga 10 mm/kum khatah
(6) Corrosion-resistant lo: corrosion rate chu kum khatah 10 mm aia tam a ni
Corrosion dona kawng 9 a ni
1. Corrosive medium angin corrosion-resistant materials thlang rawh
A siam chhuah tak takah chuan medium-a corrosion hi a buaithlak hle a, medium khata valve material hman chu inang mah se, medium concentration, temperature leh pressure a inang lo va, medium leh material corrosion chu a inang lo hle. Medium temperature 10°C a san apiangin corrosion rate chu a let 1~3 velin a pung thin.
Medium concentration hian valve material corrosion-ah nghawng lian tak a nei a, chu chu lead chu sulfuric acid-ah concentration tlemte nen a awm a, corrosion chu a tlem hle a, concentration 96% aia tam a nih chuan corrosion chu nasa takin a sang chho thin. Carbon steel erawh chuan sulphuric acid concentration 50% vel a nih chuan corrosion na ber a nei a, 60% aia tam a san chuan corrosion chu nasa takin a tlahniam a ni. Entirnan, aluminium hi concentrated nitric acid concentration 80% aia tam ah chuan a corrosive hle a, mahse nitric acid concentration medium leh low concentration ah chuan a corrosive nasa hle a, stainless steel hian dilute nitric acid lakah a do thei hle a, mahse 95% aia tam concentrated nitric acid ah chuan a aggravated hle.
A chunga entirnan kan tarlan atang hian valve material thlan dik chu thil awmdan bik atanga thlirin, corrosion nghawng thei thil hrang hrang thlirlet a, anti-corrosion manual kaihhnawih angin material thlan tur a ni tih a hriat theih.
2. Thir ni lo thil hman tur
Non-metallic corrosion resistance hi a tha hle a, valve temperature leh pressure hian non-metallic materials mamawh a tlin phawt chuan corrosion problem a chinfel mai bakah metal hlu tak tak te pawh a chhanhim thei bawk. Valve body, bonnet, lining, sealing surface leh thil dang hman tlanglawn tak, non-metallic material siam a ni.
Plastic PTFE leh chlorinated polyether bakah natural rubber, neoprene, nitrile rubber leh rubber dangte chu valve lining atan hman a ni a, valve body bonnet taksa ber chu cast iron leh carbon steel hmanga siam a ni. Valve chakna a tichiang mai bakah valve chu a chhe lo tih a tichiang bawk.
Tunlai hian plastic nylon leh PTFE ang chi te hman a tam ta hle a, natural rubber leh synthetic rubber hmangin sealing surface leh sealing ring hrang hrang siam a ni a, chu chu valve hrang hrangah hman a ni. Heng non-metallic materials sealing surface atana hman te hian corrosion resistance tha tak an nei mai bakah sealing performance tha tak an nei bawk a, hei hi a bik takin particle nei media-a hman atan a tha hle. Dik tak chuan an chak lo zawk a, lumna pawh an tuar thei lo va, an hmanna tur pawh a tlem hle.
3. Metal chunglam tihfai
(1) Valve connection: Valve connection snail hi boruak leh medium corrosion do theihna tur siam that nan galvanizing, chrome plating, leh oxidation (blue) hmanga enkawl a ni tlangpui. A chunga kan sawi tak bakah hian fastener dangte pawh hi thil awmdan azirin phosphating ang chi surface treatment hmangin an enkawl bawk.
(2) Seal surface leh closed parts diameter te tak te: a corrosion resistance leh wear resistance tihchangtlun nan surface process nitriding leh boronizing te hman a ni.
(3) Stem anti-corrosion: a corrosion resistance, corrosion resistance leh abrasion resistance tihchangtlun nan nitriding, boronization, chrome plating, nickel plating leh surface treatment process dangte hi hman a ni nasa hle.
Surface treatment hrang hrang chu stem material hrang hrang leh hnathawhna hmun hrang hrang atan a tha tur a ni a, boruakah, water vapor medium leh asbestos packing contact stem, hard chrome plating, gas nitriding process (stainless steel hian ion nitriding process hmang lo turin): hydrogen sulfide atmospheric environment-ah electroplating hmanga high phosphorus nickel coating hian venhimna performance tha zawk a nei a 38CrMOAIA hi ion leh gas nitriding hmangin corrosion-resistant a ni thei bawk a, mahse hard chrome coating hi hman atan a tha lo; 2Cr13 hian quenching leh tempering hnuah ammonia corrosion a do thei a, gas nitriding hmanga carbon steel hian ammonia corrosion a do thei bawk a, phosphorus-nickel plating layer zawng zawng hian ammonia corrosion a do thei lo a, gas nitriding 38CrMOAIA material hian corrosion resistance tha tak leh comprehensive performance a nei tha hle a, valve stem siam nan hman a ni ber bawk.
(4) Small-caliber valve body leh handwheel: A corrosion resistance tihchangtlun nan leh valve chei nan chrome-plated a ni fo bawk.
4. Thermal spray hmanga tihfai
Thermal spraying hi coating siamna atana process method chi khat a ni a, material surface venhimna atana technology thar zinga mi a ni ta a ni. Surface strengthening process method a ni a, high energy density heat sources (gas combustion flame, electric arc, plasma arc, electric heating, gas explosion, etc.) hmangin metal emaw non-metallic materials te chu a lum leh a ti lum a, chu chu atomization angin pretreated basic surface-ah spray hmangin spray coating siam a ni a, a nih loh leh basic surface chu a rualin a lum a, chutiang chuan coating chu surface-ah a melt leh ta a ni substrate chu spray welding layer-a surface tichaktu process siam turin.
Metal tam zawk leh an alloy, metal oxide ceramics, cermet composite leh hard metal compound te hi metal emaw non-metal substrate-ah thermal spraying method pakhat emaw, a aia tam emaw hmangin coated theih a ni a, hei hian surface corrosion resistance, wear resistance, high temperature resistance leh property dangte a ti tha thei a, service life pawh a ti rei thei bawk. Thermal spraying special functional coating, heat insulation, insulation (or electricity pangngai lo), grindable sealing, self-lubrication, thermal radiation, electromagnetic shielding leh thil dang special property nei, thermal spraying hman hian parts a siam tha thei a ni.
5. Paint hnawih rawh
Coating hi anti-corrosion hmanraw hman lar tak a ni a, valve product-a anti-corrosion material leh identification mark pawimawh tak a ni. Coating hi non-metallic material a ni bawk a, a tlangpuiin synthetic resin, rubber slurry, vegetable oil, solvent, etc. hmanga siam a ni a, metal chunglam a khuh a, medium leh boruak chu a inthen a, anti-corrosion tumna a hlen chhuak a ni.
Coatings hi tui, tui chi, tuifinriat tui, boruak leh boruak dang, a chhe lutuk loah te hman a ni ber. Valve chhung lam hi tui, boruak leh media dangte’n valve a tihchhiat loh nan anticorrosive paint hmanga chei a ni fo thin
6. Corrosion inhibitor te dah tel bawk ang che
Corrosion inhibitor te hian corrosion an control dan mechanism chu battery polarization a tichak a ni. Corrosion inhibitor hi media leh filler-ah te hman a ni ber. Medium-a corrosion inhibitor dah belh hian hmanrua leh valve-te corrosion a tikhawtlai thei a, chu chu oxygen-free sulfuric acid-a chromium-nickel stainless steel, solubility range lian tak chu cremation state-ah a awm a, corrosion hi a na zawk a, mahse copper sulfate emaw nitric acid leh oxidant dang tlemte dah belh chuan stainless steel chu blunt state-ah a chantir thei a, a chunglam chu protective a ni film siamin medium a erosion loh nan, hydrochloric acid-ah oxidant tlem te te dah tel a nih chuan titanium corrosion chu a tlahniam thei a ni.
Valve pressure test hi pressure test na atan hman a ni fo a, hei hian corrosion a siam awlsam hlevalve a ni, leh tuiah sodium nitrite tlemte dah chuan tuiin valve a tihchhiat loh nan a veng thei bawk. Asbestos packing-ah hian chloride a awm a, hei hian valve stem chu nasa takin a tichhe a, steaming water washing method hman a nih chuan chloride awm zat a tlahniam thei a, mahse he method hi hman a harsa hle a, a tlangpuiin a lar thei lo va, mamawh bik tan chauh a tha hle.
Valve stem venhimna tur leh asbestos packing-a corrosion venna atan asbestos packing-ah hian corrosion inhibitor leh sacrificial metal chu valve stem-ah coated a ni a, corrosion inhibitor chu sodium nitrite leh sodium chromate hmanga siam a ni a, hei hian passivation film a siam thei a, valve stem chung lamah passivation film a siam thei a, valve stem-a corrosion resistance a ti tha thei bawk a, solvent hian corrosion a siam thei bawk inhibitor chu zawi zawiin a lo hmin a, lubricating role a nei a; Dik tak chuan zinc hi corrosion inhibitor a ni bawk a, asbestos-a chloride nen a inzawm hmasa thei a, chutiang chuan chloride leh stem metal contact opportunity chu nasa takin a tlahniam a, chutiang chuan anti-corrosion tum chu a thleng thei a ni.
7. Electrochemical hmanga invenna
Electrochemical protection hi chi hnih a awm a, chungte chu anodic protection leh cathodic protection te an ni. Zinc hi iron venna atana hman a nih chuan zinc a corroded a, zinc hi sacrificial metal an ti a, production practice-ah chuan anode protection hman tlem a ni a, cathodic protection hman tam a ni. He cathodic protection method hi valve lian leh valve pawimawh tak tak tan hman a ni a, hei hi hmanraw man tlawm, awlsam leh tangkai tak a ni a, asbestos packing-ah hian zinc dahin valve stem venhim a ni.
8. Environment chhe thei (corrosive environment) control tur
Environment an tih hian broad sense leh narrow sense chi hnih a nei a, broad sense of environment tih hian valve dahna hmun leh a chhunga circulation medium chhehvel boruak a kawk a, narrow sense of environment tih hian valve dahna hmun vel boruak a kawk bawk.
Environment tam zawk hi chu thunun theih loh a ni a, thil siam chhuah dan pawh duh duhin tihdanglam theih a ni lo. Product leh process tihchhiat a awm loh phawt chuan environment control dan tur chu hman theih a ni a, chu chu boiler tui deoxygenation, oil refining process-a PH value siamrem nan alkali dah belh, etc. Hetiang atang hian a chunga kan sawi tak corrosion inhibitor leh electrochemical protection te dah belh hi corrosive environment control dan tur a ni bawk.
Boruak hi leivut, tui hnim leh meikhuin a khat a, a bik takin thil siamna hmunah chuan meikhu brine, toxic gas leh hmanrua atanga powder tha tak chhuak te a awm a, chu chuan valve chu a tichhe nasa hle ang. Operator chuan a hnathawh dan tur ruahmanna angin valve leh fuel chu a tifai fo tur a ni a, a tifai fo tur a ni a, hei hi environment corrosion control nana hmanraw tangkai tak a ni. Valve stem-a protective cover dah te, ground valve-a ground well dah te, valve chunglamah paint spray te hi thil chhe thei thilin a tihchhiat loh nan a pui vek a nivalve a ni.
Ambient temperature leh boruak bawlhhlawh tihpun hian a bik takin boruak khar chhunga hmanrua leh valve te tan chuan an corrosion a ti chak dawn a, open workshop emaw ventilation leh cooling measures emaw hmangin environment corrosion tihtlem nan a theih ang anga hman tur a ni.
9. Processing technology leh valve structure tihchangtlun
A anti-corrosion laka invenna chu a...valve a nitih hi design bul a\anga ngaihtuah tawh harsatna a ni a, valve product structural design mumal tak leh process method dik tak nei chuan valve-a corrosion tihziaawmna kawngah nghawng \ha tak a nei ngei ang tih rinhlelh rual a ni lo. Chuvangin, design leh manufacturing department chuan structural design-a a remchan loh, process method dik lo leh corrosion thlen awlsam tak takte chu hnathawh dan hrang hrang mamawh ang zela siam that a ngai a ni.
Post hun chhung: Jan-22-2025
