Sekhahla sa Phallo ke eng
Phallo ea Motsoako, e tsejoang e le Cv (US/EU Standard), Kv (International Standard), kapa boleng ba C, ke paramethara ea bohlokoa ea tekheniki e hlalosang bokhoni ba phallo ea li-valve tsa indasteri joalo ka li-valve tsa taolo le balaoli.
Ho Hlalosa Boleng ba Cv
Valve Cv e emela coefficient ea phallo e bontšang bokhoni ba valve ba ho fetisa mokelikeli tlas'a maemo a itseng. E lekanya sekhahla sa phallo ea mokelikeli kapa khase ka har'a valve ka ho theoha ha khatello ho fanoeng. Litekanyetso tse phahameng tsa Cv li bontša bokhoni bo boholo ba phallo.
Cv ke eng (Boleng ba Bokgoni)
Valve Cv (Boleng ba Bokgoni) e lekanya bokgoni ba phallo mme e balwa tlasa maemo a teko a tloaelehileng:
• Valve e bulehile ka botlalo
• Ho theoha ha kgatello (ΔP) ya 1 psi ho pholletsa le valve
• Mokelikeli: Metsi a 60°F (15.5°C)
• Sekhahla sa phallo: Ligalane tsa US ka motsotso (GPM)
Boleng ba ho Buloa ha Valve khahlanong le Cv
Cv/Kv le ho buloa ha valve (%) ke mehopolo e fapaneng:
• Tlhaloso ea Kv (Tekanyetso ea Chaena):Sekgahla sa phallo ka m³/h ha ΔP = 100 kPa, bongata ba mokelikeli = 1 g/cm³ (metsi mochesong wa kamore).
*Mohlala:Kv=50 e bolela phallo ea 50 m³/h ho 100 kPa ΔP.*
• Peresente ea ho Bula:Sebaka sa polaka/disiki ya valve (0% = e kwetswe, 100% = e butswe ka botlalo).
Ho Bala Litšebeliso tsa Cv le Key
Cv e susumetsoa ke moralo oa li-valve, boholo, thepa, tsamaiso ea phallo, le litšobotsi tsa mokelikeli (mocheso, khatello, ho teteana).
Foromo ea mantlha ke:
Cv = Q / (√ΔP × √ρ)
Moo:
• P= Sekhahla sa phallo ea molumo
•ΔP= Phapang ea khatello
•ρ= Bongata ba mokelikeli
Phetoho: Cv = 1.167 Kv
Karolo Khethong le Moralong oa Li-valve
Cv e ama ka kotloloho bokgoni ba tsamaiso ya taolo ya mokelikeli:
•E khetholla boholo le mofuta o nepahetseng oa valve bakeng sa sekhahla sa phallo ea sepheo
•E netefatsa botsitso ba sistimi (mohlala, e thibela ho potoloha ha pompo phepelong ea metsi a kaho)
•Bohlokoa bakeng sa ntlafatso ea matla
Mefuta ea Cv ho pholletsa le Mefuta ea Valve
Bokgoni ba phallo bo fapana ho ya ka moralo wa di-valve (data e fumanweng hoLitekanyetso tsa ASME/API/ISO):
| Mofuta oa Valve | Litšobotsi tsa Bohlokoa | Mohlala oa Cv (Tekanyetso ea FCI) |
|---|---|---|
Valve ea Heke | Cv e Mahareng (DN100 ≈ 400); taolo e fokolang; qoba ho buleha ho ka tlase ho 30% (kotsi ea pherekano ho latela ASME B16.34) | DN50: ~120 |
Valve ea Bolo | Cv e Phahameng (li-valve tsa heke tse 1.8×); taolo ea phallo e otlolohileng; API 6D e khothaletsoa bakeng sa liphaephe | DN80 V-bolo: ≈375 |
Valve ea Serurubele | E theko e tlase bakeng sa boholo bo boholo; ho nepahala ha ±5% (ho fokotsa makhetlo a mararo); keketseho e fokolang ea phallo >70% e bulehile | DN150 Wafer: ~2000 |
Valve ea Lefatše | Khanyetso e phahameng (Cv ≈ 1/3 ea li-valve tsa bolo); taolo e nepahetseng (tšebeliso ea bongaka/lab) | DN50: ~40 |
Liparamente tsa Phallo ea Motheo le Lintlha tse Susumetsang
Tshebetso ya valve e hlaloswa ke diparamithara tse tharo (ho ya ka Setsi sa Taolo ya Mokelikeli):
1. Boleng ba CV:Phallo ea GPM ho 1 psi ΔP (mohlala, valve ea bolo ea DN50 ≈ 210 khahlano le valve ea heke ≈ 120).
2. Koefficient ea ho Hanela Phallo (ξ):
•Valve ea serurubele: ξ = 0.2–0.6
•Valofo ea lefats'e: ξ = 3–5
Tataiso ea Khetho le Lintlha tsa Bohlokoa
Tokiso ea ho thibana ha mahlo:
Kenya li-multiplier ho Cv (mohlala, oli e tala: 0.7–0.9 ho ea ka ISO 5208).
Li-valve tse bohlale:
Ntlafatso ea Cv ea nako ea sebele (mohlala, Emerson DVC6200 positioner).
Mekhoa ea Teko ea Phallo ea Phallo
Teko e hloka maemo a laoloang ka lebaka la kutloisiso ea tekanyo:
•Setaele (Ho ya ka Setshwantsho sa 1):
Sesupa-nako sa phallo, thermometer, li-valve tsa ho phunya, valve ea teko, gauge ea ΔP.
1. Seteishene sa phallo 2. Thermometer 3. Valve ea throttle e nyolohang 4 le 7. Masoba a ho penya khatello 5. Valve ea teko 6. Sesebelisoa sa ho lekanya phapang ea khatello 8. Valve ea throttle e theohelang tlaase
4. Sebaka se pakeng tsa lesoba la ho penya kgatello le valve se feta bophara ba phaephe ka makgetlo a mabedi
7. Sebaka se pakeng tsa lesoba la ho penya kgatello le valve se feta bophara ba phaephe ka makgetlo a 6
•Litaolo tsa Bohlokoa:
- Valve e nyolohang e laola khatello ea ho kena ha metsi.
- Valve e theohelang e boloka khatello e tsitsitseng (boholo bo tloaelehileng > valve ea teko ho netefatsa hore phallo e khangoa e etsahalainvalve ea teko).
•Maemo:
JB/T 5296-91 (Chaena) khahlano le BS EN1267-1999 (EU).
•Mabaka a Bohlokoa:
Sebaka sa ho tobetsa, tlhophiso ea liphaephe, nomoro ea Reynolds (metsi), nomoro ea Mach (likhase).
Meeli ea Teko le Litharollo:
•Li-valve tsa liteko tsa sistimi ea hona joale ≤DN600.
•Li-valve tse kholoanyane:Sebelisa teko ea phallo ea moea (ha e so hlalosoe mona).
Tšusumetso ea Nomoro ea Reynolds: Lintlha tsa liteko li tiisa hore palo ea Reynolds e ama liphetho tsa liteko haholo.
Lintlha tsa Bohlokoa
•Cv/Kv e hlalosa bokgoni ba phallo ya valve tlasa maemo a tloaelehileng.
•Mofuta oa valve, boholo, le thepa ea mokelikeli li ama Cv haholo.
•Teko e hloka ho latela melaoana ka tieo (JB/T 5296-91/BS EN1267) bakeng sa ho nepahala.
•Litokiso li sebetsa bakeng sa ho teteana, mocheso le khatello.
(Data yohle e fumanwe ho tsoa ho maemo a ASME/API/ISO le dipampiri tse tshweu tsa moetsi wa di-valve.)
Nako ea poso: Pherekhong-06-2025