Lub rooj zaum thiab lub nplhaib lub rooj zaum yog cov tseem ceeb ntawm kev sib khi ntawm cov khoom siv thiab cov khoom siv tswj kev lag luam. Kev xaiv cov khoom siv tsis raug ua rau muaj kev yaig ntxov ntxov, cavitation puas tsuaj, hlau galling thiab nruam sab hauv to, uas ua rau cov kav dej tsis tau npaj tseg thiab cov nqi kho mob siab. Cov lus qhia no suav nrog cov qauv ntawm lub rooj zaum, cov qauv tsis ua haujlwm, cov khoom sib piv ntawm cov hlau tsis muaj steel thiab Stellite alloys, peev casting qauv thiab cov txheej txheem machining, pab cov engineers thiab cov neeg yuav khoom tuaj yeem xaiv lub rooj zaum valve, lub nplhaib thiab valve ntxig rau roj & roj, tshuaj lom neeg thiab chav ua haujlwm.
1. Txheej txheem cej luam ntawm Valve Rooj & Lub Rooj Ntiv Nplhaib hauv Kos Valve
1.1 Kev txhais thiab cov qauv sib txawv
Nqe lus teb no: Dab tsi yog qhov txawv ntawm lub rooj zaum valve, lub nplhaib lub rooj zaum thiab lub valve ntxig? Lub luag haujlwm no ua haujlwm li cas hauv daim tshev valve sealing?
- Valve rooj: Lub hauv paus ruaj khov sib xyaw ua ke los yog nias rau hauv lub cev lub cev, uas ua rau thawj qhov sib txuas nrog lub valve disc lossis pob.
- Lub rooj zaum nplhaib (check valve nplhaib): Ib lub nplhaib hloov tau zoo li qhov ntxig ntxig rau ntawm lub rooj tog zaum; nws ua hauj lwm raws li lub sacrificial sealing nto los tiv thaiv lub valve lub cev los ntawm hnav.
- Valve insert: Ib qho nqaim sealing band machined ntawm lub nplhaib lub rooj zaum, feem ntau hardfaced nrog Stellite alloy rau kev pabcuam hnyav.
Lub viav vias kos li qub thiab nqa cov tshev valve txais yuav cov qauv rooj sib txawv. Nqa daim tshev li qub muaj lub tiaj tiaj, nqaim lub rooj zaum, thaum lub viav vias kos li qub siv lub ntsej muag dav arc-zoo li lub ntsej muag. Tag nrho cov hlau-rau-hlau sealing kev ua tau zoo yog nyob ntawm cov khoom zoo thiab kev ua haujlwm zoo ntawm peb cov khoom.
1.2 Qhov tshwm sim ntawm Lub Rooj Failure
Thaum lub rooj zaum sealing nto puas lawm, lub valve tsis tuaj yeem thaiv rov qab tau zoo. Cov txiaj ntsig tau pom muaj xws li qhov nruab nrab tsis tu ncua, kev poob siab zuj zus, thiab hloov lub valve tag nrho hauv lub hlis es tsis txhob xyoo.
2. Hom Kev Ua Tsis Zoo ntawm Valve Rooj & Lub Rooj Ntiv Nplhaib
Tshooj lus no tsuas yog piav qhia txog kev ua tsis tiav yam tsis muaj kev qhia txog cov khoom siv daws teeb meem.
2.1 Erosion Wear (Particle Impingement & Wire Drawing)
High-velocity kua nqa cov khoom uas txiav tawm cov kab grooves ntawm lub ntsej muag sealing. Qhov tshwm sim no yog hu ua hlau kos duab, thiab nws nquag tshwm sim nyob rau hauv high-pressure chav thiab slurry pipelines. Cov khoom tawv tawv ua rau muaj kev cuam tshuam kev hnav, maj mam tshem cov khoom ntawm lub rooj zaum band.
2.2 Cavitation puas (Flashing & Npuas Collapse)
Thaum cov kua siab poob qis hauv qab vapor siab, kua flashes rau hauv vapor npuas. Cov npuas no tawg hnyav thaum lub siab rov qab los, ua rau muaj kev kub ntxhov hauv cheeb tsam uas tsim pitting thiab crater puas tsuaj ntawm lub rooj zaum hlau. Cavitation yog dav nyob rau hauv throttling tswj li qub thiab siab sib txawv siab check li qub.
2.3 Galling & Adhesive Hnav ntawm Hlau Sealing Surfaces
Thaum ob qhov chaw hlau liab qab rov qhib thiab kaw nyob rau hauv kev sib cuag siab, txias vuam tshwm sim ntawm cov ntsiab lus sib cuag. Cov khoom ua kua muag tawm ntawm ib qho chaw thiab lo rau lub ntsej muag mating, ua rau qaug dab peg mus tas li. Stainless hlau khub yog heev nquag mus galling yam tsis muaj hardfacing kho.
3. Cov khoom siv hlau tseem ceeb rau Kev Tshawb Fawb Lub Rooj Zaum & Lub Rooj Zaum Ring
3.1 316L Stainless hlau (CF3M / F316L) - General Corrosion Service
- Hardness: Kwv yees li 25 HRC nyob rau hauv annealed mob.
- Qhov zoo: Zoo heev tiv thaiv corrosion thiab chloride corrosion; tus nqi qis; yooj yim peev casting thiab machining.
- Txwv tsis pub: hnav tsis zoo; tsis tuaj yeem tiv taus yaig, cavitation lossis galling nyob rau hauv siab.
- Kev pabcuam tsim nyog: Cov dej huv huv, cov kua dej me me, cov kav dej tsis muaj zog tsis muaj cov khoom siv.
3.2 420 Martensitic Stainless Hlau - Kev Pab Cuam Nruab Nrab
- Hardness: 38-42 HRC tom qab quenching thiab tempering.
- Qhov zoo: Siab hardness dua 316L; zoo dua los tiv thaiv kev hnav; pheej yig rau kev pabcuam nruab nrab.
- Kev txwv: txwv cavitation tsis kam; tseem ua rau khaus thaum ua ke nrog lwm lub ntsej muag 420 stainless hlau.
- Kev pabcuam tsim nyog: Cov kua dej tsis tshua muaj siab, tsis tshua muaj lub voj voog ntawm-tawm kos li qub.
3.3 Stellite Alloys (Stellite 6 / Stellite 12) - Kev Ua Haujlwm Loj & Cavitation
Stellite yog cobalt-chromium-tungsten alloy dav siv los ua hardfacing overlay ntawm stainless hlau rooj zaum substrates.
Stellite 6 (Industry Standard Qib)
- Hardness: 36-45 HRC tom qab vuam overlay.
- Kev ua haujlwm tseem ceeb: Kev ua haujlwm zoo rau cavitation, yaig thiab hlau galling; khaws cov hardness feem ntau mus txog 500 ° C high-temperature chav pab.
- Daim ntawv thov: High-pressure steam, nruab nrab slurry, high-cycle modulating check li qub thiab tswj li qub.
Stellite 12 (High-wear Qib)
- Hardness: 45-53 HRC nrog cov ntsiab lus carbon ntau dua.
- Kev lag luam tawm: Kev puas tsuaj ntau dua tab sis qis dua qhov hnyav dua li Stellite 6; yooj yim dua rau kev tawg nyob rau hauv qhov hnyav.
- Daim ntawv thov: Qhov hnyav abrasive slurry thiab hnyav yaig.
| Khoom siv | Hardness (HRC) | Hom Kev Pabcuam Nruam Kub | Zoo tshaj rau |
| 316L Stainless hlau | ~ 25 | Txog li 870 ° C | Me me corrosion, huv nruab nrab |
| 420 Stainless hlau | 38–42 : kuv | Txog li 450 ° C | Nruab nrab hnav, tsis tshua muaj siab |
| Stellite 6 Hardfacing | 36–45 : kuv | Txog li 500 ° C | Chav, cavitation, anti-galling kev pab |
| Stellite 12 Hardfacing | 45–53 : kuv | Txog li 500 ° C | Loj particle erosion |
4. Kev tsim khoom tseem ceeb & Machining Requirements
4.1 Kev nqis peev Casting Cov ntsiab lus tseem ceeb rau Valve Seat Inserts
Feem ntau valve rooj rings thiab inserts yog tsim los ntawm silica sol peev casting, tshwj xeeb tshaj yog rau 316L thiab Stellite alloy Cheebtsam.
- Tswj shrinkage porosity thiab kub tearing nyob ze ntawm lub sealing band los ntawm optimizing rooj vag thiab txias layout; tsis txhob casting qhov tsis xws luag ntawm qhov tseem ceeb sealing nto.
- Tag nrho tshem tawm cov khoom siv ceramics ua ntej machining; residual xuab zeb yuav ua rau ntxov ntxov hnav thaum lapping.
- Siv cov kev ntxhov siab rau kev kho cua sov tom qab casting los tiv thaiv qhov deformation nyob rau hauv cyclic kub hloov.
- Kev tshuaj xyuas NDT: Ua qhov kev sim nkag siab (PT) thiab kuaj hluav taws xob (RT) ntawm lub rooj zaum ua tiav txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau sab hauv thiab cov kab nrib pleb.
4.2 Hardness Standard rau Sealing Surfaces
- Uncoated stainless hlau rooj zaum yuav tsum tau raws li cov txheej txheem hardness; mating disc lub ntsej muag yuav tsum muaj qhov sib txawv hardness tsawg kawg yog 5 HRC kom txo qis kev pheej hmoo ntawm galling.
- Stellite hardfacing overlay thickness yog tswj ntawm 2-4 mm tom qab ua tiav machining; hardness yuav tsum raug kuaj ncaj qha rau ntawm hardfaced sealing band, tsis yog nyob rau hauv stainless hlau substrate.
- Sour oil & gas service (NACE MR0175): Hardness txwv siv kom tsis txhob muaj sulfide kev nyuaj siab tawg; Stellite 6 yog tsim nyog rau kev pabcuam roj qaub nrog kev tswj kom zoo.
4.3 Nto Finish & Lapping Requirements rau cov rooj zaum hlau
Nto roughness ncaj qha cuam tshuam rau sealing nruj thiab kev pab lub neej.
- Machined lub rooj zaum: Ra 0.8-1.6 μm rau dav hlau-seated check li qub.
- Lapped sealing ntsej muag rau Chav Kawm V / VI xoom-leakage shutoff (ib API valve leakage classification): Ra 0.2-0.8 μm nrog flatness tswj nyob rau hauv 2 lub teeb bands (0.0005 mm).
- Tsis txhob hlaws blasting lossis tumbling tom qab machining kawg; blasting tsim qhov tsis sib xws ntawm qhov zoo nkauj thiab ua rau lub neej luv.
- Precision lapping yog yuav tsum tau rau Stellite Valve Pob thiab rooj zaum mating khub kom ua tau raws li kev sib cuag thoob plaws lub rooj zaum dav.
5. Cov ntsiab lus xaiv cov khoom siv raws li kev pabcuam
Tshooj lus no muab cov cai xaiv ua tau yam tsis tau rov ua cov ntaub ntawv ua haujlwm tag nrho.
5.1 Huv nruab nrab & me me Corrosion
Nruab Nrab: Cov dej ntshiab huv, qhov kub thiab txias tsis muaj dej huv, cov pa roj tsawg uas tsis muaj cov khoom siv.
Cov khoom pom zoo: Khoom 316L stainless hlau valve lub rooj zaum thiab lub nplhaib lub rooj zaum. Tsis muaj Stellite hardfacing yuav tsum tau tswj tus nqi yuav khoom.
5.2 High-Pressure Steam & Erosive Fluid
Nruab nrab: Saturated thiab superheated chav, kua dej nrog cov khoom muag muag, siab khiav ceev.
Cov khoom siv pom zoo: 316L substrate nrog Stellite 6 hardfacing ntawm lub sealing band, tiv thaiv cov hlau nqus yaig thiab kub kub oxidation.
5.3 Cavitation & Flashing Service
Nruab nrab: Siab sib txawv siab throttling, flashing kua, nquag npuas vau.
Cov khoom pom zoo: Stellite 6 overlay lub rooj ntxig; cobalt-raws li alloy muab deb zoo cavitation tsis kam tshaj martensitic stainless hlau.
5.4 Sour Oil & Gas Service (NACE MR0175 txwv)
Nruab nrab: H₂S-muaj qaub crude thiab natural gas.
Txoj cai tseem ceeb: Tswj lub rooj hardness hauv qab NACE tau teev saum toj kawg nkaus txwv; Stellite 6 hardfacing ua tau raws li NACE MR0175 / ISO 15156 tus qauv rau sulfide kev ntxhov siab tawg ua haujlwm. Tsis txhob muaj kev tswj xyuas qhov siab-hardness weld overlays.
6. Cov lus nug uas nquag nug
6.1 Stellite Valve Rooj vs 316L: Uas Muaj Kev Pabcuam Ntev?
Stellite hardfaced cov rooj zaum xa cov kev pab cuam lub neej ntev dua li liab qab 316L rooj zaum hauv chav dej, cavitation thiab erosive tej yam kev mob. Rau cov kev pabcuam uas tsis tshua muaj siab, 316L muab lub neej txaus nrog tus nqi qis dua.
6.2 Puas tuaj yeem siv Stellite Hardfacing nyob rau hauv Kev Pabcuam Sour Gas?
Yog lawm. Stellite 6 ua raws li NACE MR0175 / ISO 15156 thaum weld hardness yog nruj me ntsis tswj, ua rau nws yog ib tug txheej txheem trim khoom rau qaub roj & roj check li qub.
6.3 Dab tsi yog qhov yuav tsum tau muaj Hardness rau Kos Valve Rooj Ring?
- 316L lub rooj zaum: 22-28 HRC (lub xeev annealed).
- 420 stainless hlau lub rooj: 38-42 HRC tom qab kev kho cua sov.
- Stellite 6 hardfaced lub rooj: 36-45 HRC ntsuas ntawm qhov chaw overlay.
7. Cov lus xaus & Cov ntsiab lus xaiv
Lub hauv paus ntsiab lus tseem ceeb rau lub rooj zaum lub rooj zaum thiab lub rooj zaum lub nplhaib xaiv cov khoom siv yog txuam nrog kev ua haujlwm zoo rau hom tsis ua haujlwm tseem ceeb:
- Rau cov kav dej huv, tsis tshua muaj corrosion: Xaiv cov khoom 316L stainless hlau valve ntxig thiab lub nplhaib lub rooj zaum kom txuag tau nqi.
- Rau siab-siab chav, particle yaig thiab cavitation kev pab cuam: Qhia Stellite 6 hardfacing ntawm 316L substrates.
- Rau kev pabcuam roj qaub: Ua raws NACE MR0175 hardness txwv thiab xaiv tsim nyog Stellite overlay.
- Nco ntsoov xyuas qhov zoo ntawm casting, nto tiav thiab sealing lub ntsej muag hardness ua ntej txais.
Thaum soj ntsuam kev cai kos lub rooj zaum, lub nplhaib lub rooj zaum thiab Stellite Valve Pob thiab lub rooj sib txoos rau cov tshuab ua kua, paub meej tias cov txheej txheem casting, hardfacing specification thiab lapping qauv nrog koj cov khoom lag luam kom tsis txhob muaj kev sib khi ua ntej ntxov.
