Siab - lub zog bolts: kev tsom xam los ntawm cov ntaub ntawv mus rau kev kho cua sov
1 Taw qhia rau siab - lub zog bolts
1.1 Siab - lub zog bolt qauv
Hauv kev lag luam thoob ntiaj teb thiab kev ua haujlwm txawv teb chaws, siab - lub zog bolts feem ntau ua raws li cov qauv tseem ceeb hauv qab no kom ntseeg tau tias lawv cov khoom siv, cov khoom siv kho tshuab, kev kho cua sov, thiab lwm yam. ua tau raws li cov kev cai tsim nyog:
TS EN ISO 898-1
Cov txheej txheem no tau siv dav thoob ntiaj teb (tshwj xeeb tshaj yog nyob hauv Europe thiab lwm cov haujlwm thoob ntiaj teb) thiab qhia txog cov khoom siv ntawm cov pa roj carbon steel thiab alloy steel fasteners xws li tensile zog, yield zog, hardness, elongation thiab torque coefficient.
Cov qhab nia muaj zog hauv ISO 898-1 yog 8.8, 10.9, thiab 12.9, uas yog cov ntaub ntawv tseem ceeb heev rau kev tsim khoom thiab kev lees txais cov bolts muaj zog.
ASTM A 490 Cov Lus Qhia Tshwj Xeeb
Muaj feem xyuam rau alloy steel qauv bolts, qhov tsawg kawg nkaus tensile lub zog yog feem ntau yuav tsum tau mus txog 150ksi (txog 1034MPa).
Hom ntsia liaj qhov rooj no feem ntau siv rau hauv kev sib txuas ntawm cov qauv steel uas xav tau lub zog siab, xws li txuas hniav, cov tsev siab -nce, thiab cov tshuab loj.
ASTM A 354 Cov khoom siv raw khoom
Cov txheej txheem no yuav tsum tau bolts kom muaj cov khoom siv zoo heev rau kev siv hauv qhov hnyav.
Nws yog feem ntau siv nyob rau hauv tej yaam num uas muaj kev ruaj ntseg yam thiab durability yog ib qho tseem ceeb, xws li hnyav machinery thiab tej yam khoom tshwj xeeb.
Cov qauv no tau muab cov ncauj lus kom ntxaws txog cov khoom siv qib, cov khoom siv kho tshuab, kev kho cua sov, thiab lwm yam. Piv nrog rau cov bolts zoo tib yam ntawm qib 4.6, qib 8.8 lossis qib 10.9, siab - lub zog bolts muaj qib siab zog (xws li qib 12.9) thiab cov khoom siv nruj dua kom ua tau raws li cov txheej txheem kev tswj thiab kev nyab xeeb.
1.2 Kev ua tau zoo ntawm siab - lub zog bolts
Lub "siab zog" ntawm siab - lub zog bolts tsis yog tsuas yog xav txog lub zog tensile, tab sis kuj nyob rau hauv cov kev xav tau ntawm yield zog, elongation, cuam tshuam toughness thiab lwm yam ntsuas. Feem ntau hais lus, ntawm cov qib siab - lub zog bolt hauv Tebchaws Meskas, qhov tsawg kawg nkaus tensile lub zog ntawm cov bolts tuaj yeem ncav cuag ntau dua 1000MPa, thiab qee cov hlau alloy steel bolts tuaj yeem ncav cuag qhov ntau ntawm 1200 ~ 1400MPa. Tsis tas li ntawd, txhawm rau kom ntseeg tau tias muaj kev sib txuas hauv ntau qhov chaw ua haujlwm, siab - lub zog bolts yuav tsum muaj cov yam ntxwv ua tau zoo hauv qab no:
Toughness thiab ductility
Nyob rau hauv ib puag ncig huab cua los yog nyob rau hauv dynamic thiab cuam tshuam loads, lub toughness thiab ductility ntawm cov ntaub ntawv feem ntau tseem ceeb tshaj lub zog. Tshwj xeeb tshaj yog rau cov bolts uas yuav tsum tau ua hauj lwm nyob rau hauv tsis tshua muaj kub ib puag ncig (xws li - 20℃los yog -40 degree), nws yog feem ntau yuav tsum tau hais tias tus Charpy cuam tshuam tus nqi ntawm high-lub zog bolts ntawm qhov sib xws kub yuav tsum tau khaws cia tsawg kawg yog 27J ~ 40J los tiv thaiv brittle puas; nyob rau hauv lub teb ntawm polar lossis offshore cua fais fab, qhov kev xeem yuav tsum tau nce ntxiv mus rau -50℃lossis qis dua.
Tsis tas li ntawd, rau 10.9 lossis 12.9 qib bolts, qhov elongation (A5) feem ntau yuav tsum ncav cuag 8% ~ 14%, thiab tus ntoo khaub lig-sectional txo (Z) feem ntau yuav tsum siab tshaj 40% ~ 50% kom ntseeg tau tias cov yas deformation txaus thiab kev nyab xeeb. Nyob rau hauv luv luv, txhawm rau tswj kev ntseeg tau ntev nyob rau hauv cov xwm txheej hnyav, nws tsis txaus los tsom rau lub zog siab ib leeg, toughness thiab ductility yog qhov tseem ceeb sib npaug.
Nthuav lub neej
Nyob rau hauv ib qho chaw uas muaj kev vibration tsis tu ncua los yog alternating loads, bolts nrog tsis txaus qaug zog tiv thaiv yog feem ntau ua rau qaug zog tawg ntawm lub hauv paus ntawm cov xov los yog kev nyuaj siab concentration, nws thiaj li ua rau puas.
Corrosion kuj
Rau siab - lub zog bolts siv nyob rau hauv marine engineering, petrochemical khoom los yog ib puag ncig ntub, kev kho saum npoo los yog ntxiv cov hlau alloy tshwj xeeb xws li chromium (Cr) thiab npib tsib xee (Ni) feem ntau yuav tsum tau txhim kho corrosion kuj.
1.3 Kev siv siab - lub zog bolts
High - lub zog bolts muaj cov yam ntxwv ntawm kev thauj khoom siab -cov kabmob muaj peev xwm, zoo toughness thiab lub neej ua haujlwm ntev.
Lawv feem ntau siv nyob rau hauv lub sijhawm hauv qab no:
- Cov qauv hlau loj: xws li txuas hniav, cov chaw tsim khoom hnyav, cov cua turbine yees thiab cov thav duab ntawm cov tsev siab -nce
- Automotive thiab aerospace kev lag luam: kev sib txuas tseem ceeb ntawm cov cav, chassis thiab cov khoom siv dav hlau
- Petroleum, petrochemical, fais fab kev lag luam: siab hlab ntsha, pipeline flange sib txuas, li qub, khoom siv hluav taws xob nuclear
- Cov cuab yeej siv hnyav thiab tshuab: cov tshuab mining, khoom siv tub rog, nkoj tsim thiab lwm yam siab -load Cheebtsam
Nws yog tsim nyog sau cia tias "lub zog siab" tsis txhais hais tias kev nrhiav lub zog siab tshaj plaws. Yog tias qhov project ua haujlwm nyob rau hauv qhov chaw kub tsis tshua muaj siab, ntxiv rau lub zog, qhov cuam tshuam toughness thiab cov khoom muaj pes tsawg leeg ntawm cov bolts yuav tsum tau ua tib zoo xav txog. Yog tias qhov project raug kub thiab corrosive media, alloy steels nrog cov kub kub tsis kam lossis corrosion kuj yuav tsum tau xaiv. Yog li ntawd, nyob rau hauv lub bolt xaiv thiab procurement theem, cov kev ua hauj lwm tej yam kev mob thiab mechanical kev ua tau zoo ntawm cov khoom yuav tsum raug soj ntsuam xyuas, thiab "siab tshaj lub zog" yuav tsis tau mus nrhiav blindly.
2. High -cov ntaub ntawv muaj zog bolt
Qhov zoo ntawm cov khoom siv raw yog lub hauv paus rau kev txiav txim siab qhov zoo thiab kev ua haujlwm ntawm bolts. Siab - lub zog bolts feem ntau yog siv cov qauv hlau alloy xws li 42CrMo, B7, thiab 40CrNiMo. Cov ntaub ntawv no muaj cov khoom siv zoo heev nyob rau hauv qhov kub thiab txias, siab load lossis cuam tshuam, thiab tuaj yeem ua tau raws li qhov yuav tsum tau muaj ntawm qhov kub thiab txias toughness lossis corrosion tsis kam mus rau qhov sib txawv.
2.1 Cov qib steel feem ntau rau siab - lub zog bolts
Cov hauv qab no yog ob peb qib steel thiab lawv cov npe thoob ntiaj teb / US:
42CrMo (internationally common alloy steel qib, sib xws rau US ASTM B7 muaj pes tsawg leeg):
Nws muaj lub zog siab thiab hardenability, nrog lub zog tensile feem ntau 1100-1300MPa lossis siab dua, haum rau kev tsim 10.9 lossis 12.9 qib bolts.
B7 (US ASTM A193 alloy steel qib):
Cov muaj pes tsawg leeg ntawm B7 zoo ib yam li 42CrMo, tab sis cov ntsiab lus molybdenum (Mo) yog tswj tau ntau dua. B7 feem ntau yog siv rau hauv qhov kub thiab txias ib puag ncig, tshwj xeeb tshaj yog rau flange kev sib txuas ntawm cov khoom siv petrochemical.
40CrNiMo (feem ntau siv hauv ASTM A320 L7 tus qauv, thiab lwm yam.):
Cov hlau no nthuav tawm zoo dua qis- qhov kub thiab txias cuam tshuam los ntawm kev ntxiv ntau yam ntawm cov hlau alloying, thiab tuaj yeem ua haujlwm ntawm qhov kub ntawm -40℃lossis qis dua. Nws yog dav siv nyob rau hauv cov teb uas yuav tsum tau muaj qhov kub thiab txias tsis kam, xws li cua zog thiab marine engineering.
2.2 Kev ua tau zoo sib txawv ntawm cov qib steel sib txawv thiab lawv cov laj thawj
Siv 42CrMo thiab B7 ua piv txwv. Ob leeg yog nruab nrab carbon quenched thiab tempered steels (cov ntsiab lus carbon feem ntau yog 0.38% ~ 0.45%), thiab ob qho tib si muaj qee qhov nyiaj ntawm chromium (Cr) thiab molybdenum (Mo), nrog rau tag nrho cov khoom sib xws. Txawm li cas los xij, los ntawm kev tswj xyuas meej ntawm cov kab ke, tshwj xeeb tshaj yog qhov sib txawv ntawm molybdenum (Mo) thiab manganese (Mn) cov ntsiab lus, cov ntaub ntawv yuav qhia tau qhov sib txawv tseem ceeb. Piv txwv li:
Cov ntsiab lus molybdenum: Yog tias cov ntsiab lus molybdenum ntawm B7 raug tswj nruj me ntsis ntawm 0.18 thiab 0.20%, thaum cov ntsiab lus molybdenum ntawm 42CrMo yog nyob rau hauv qis kawg (0.15 ~ 0.17%), B7 muaj qhov zoo ntawm hardenability thiab cov qauv sib xws, thiab yog li ua tau zoo dua hauv kev cuam tshuam rau kev sib tw.
Manganese cov ntsiab lus: Manganese tuaj yeem txhim kho lub zog thiab hardenability nyob rau hauv ib qho chaw, tab sis ntau manganese ua rau muaj kev pheej hmoo ntawm npau taws. Thaum ua ke nrog lwm cov ntsiab lus xws li molybdenum, "kev tsis xws luag" tshwm sim los ntawm manganese tuaj yeem ua rau qee qhov txo qis, yog li tswj tau zoo toughness thaum ua kom muaj zog.
2.3 Cov txiaj ntsig ntawm txhua lub ntsiab lus ntawm cov khoom steel (cov lus)
Hauv qab no yog cov lus yooj yim uas qhia txog cov txiaj ntsig ntawm cov ntsiab lus alloying ntawm tag nrho cov khoom ntawm steel:
| Element | Lub luag haujlwm tseem ceeb | Qhov cuam tshuam rau High-Strength Bolt Performance |
| C (Carbon) | Ua kom lub zog, hardness, txo plasticity, thiab toughness | Cov ntsiab lus carbon ntau dhau ua rau kom brittleness, thaum cov ntsiab lus carbon nruab nrab pab ua kom tiav qib siab xav tau |
| Cr (Chromium) | Txhim khu kev hnav tsis kam, corrosion kuj, thiab hardenability | Cov ntsiab lus chromium siab dua txhim kho txoj hlua ruaj khov hauv siab - qhov kub thiab txias ib puag ncig |
| Molybdenum (zeeg) | Txhim kho hardenability, tiv thaiv - kub brittleness, thiab siab - qhov kub thiab txias | Pab txhim kho cov nplej thiab txhim kho qis - qhov kub thiab txias cuam tshuam thiab hnav tsis kam, tseem ceeb hauv B7 steels |
| Manganese (Mn) | Txhim kho hardenability, lub zog, thiab hnav tsis kam; Cov ntsiab lus ntau dhau tuaj yeem ua rau cov qoob loo loj hlob thiab npau taws brittleness | Yuav tsum tau sib npaug nrog lwm cov ntsiab lus txhawm rau txhim kho cov khoom siv kho tshuab thaum tsis txhob muaj qhov brittleness |
| Ni (Nickel) | Txhim kho qis -kub toughness thiab corrosion kuj, ua kom muaj zog | Cov txiaj ntsig tshwj xeeb hauv qhov qis - qhov kub thiab txias ib puag ncig xws li cua zog thiab kev tsim kho hauv hiav txwv, txhim kho qhov cuam tshuam toughness |
| V (Vanadium) | Refines grain qauv, nce lub zog thiab toughness | Thaum siv cov nqi tsim nyog, tuaj yeem txhim kho lub neej qaug zog, kev siv ntau dhau tuaj yeem ua rau kev ua haujlwm nyuaj |
Hauv cov ntsiab lus, kev xaiv cov khoom siv siab - lub zog bolts yuav tsum tau ua tib zoo sib xyaw nrog rau ib puag ncig daim ntawv thov. Thaum lub siab tawv thiab siab ductility yuav tsum tau, cov ntsiab lus ntawm molybdenum thiab npib tsib xee yuav tsum tau nce, thiab cov ntsiab lus ntawm impurities xws li sulfur thiab phosphorus yuav tsum nruj me ntsis tswj. Rau cov qauv kev thov ib puag ncig uas tsuas yog tsom rau lub zog siab yam tsis xav txog qhov nyuaj, cov hlau xws li 42CrMo tuaj yeem ua tau raws li qhov yuav tsum tau ua. Txawm li cas los xij, txhawm rau coj mus rau hauv tus account ob lub zog siab thiab qis - qhov kub thiab txias tsis kam, cov ntaub ntawv xws li 40CrNiMo lossis CrNiMo multi- cov txheej txheem alloy yuav tsum tau muab qhov tseem ceeb.
3. Kev kho cua sov ntawm siab - lub zog bolts
Kev kho cua sov yog ib kauj ruam tseem ceeb uas cuam tshuam rau kev ua haujlwm ntawm bolts. Los ntawm cua sov, kev txuag hluav taws xob thiab cua txias, cov khoom siv hauv microstructure tuaj yeem hloov pauv, thiab lub zog, ductility thiab kev cuam tshuam toughness tuaj yeem txhim kho ntxiv. Hauv kev tsim khoom tiag tiag, siab - lub zog bolts feem ntau yog "tempered" (quenching + tempering) thiab lwm yam kev kho mob (piv txwv li, dehydrogenation tempering lossis kev kho saum npoo) tau ua raws li xav tau.
3.1 Kev kho cua sov txheej txheem ntawm siab - lub zog bolts
Feem ntau, cov txheej txheem kev kho cua sov ntawm alloy structural steel siab - lub zog bolts yog raws li hauv qab no:
Preheating: Kub lub bolts txog li 600-700℃kom tso cov kev ntxhov siab sab hauv thiab txo qhov kev pheej hmoo ntawm kev tawg vim qhov kub thiab txias ntau dhau.
Austenitization: Khaws cov bolts ntawm 900℃lossis siab dua kom hloov cov tub ntxhais thiab nto rau hauv austenite thiab yaj cov ntsiab lus alloy rau hauv matrix.
quenching: Ceev ceev cov bolts rau hauv chav tsev kub los yog qis dua (feem ntau yog siv cov roj quenching los yog polymer dej txias) los hloov cov microstructure mas rau hauv martensite, ho txhim kho hardness thiab tensile zog.
Tempering: Temper lub bolts ntawm qhov tsim nyog kub (xws li . 500-650℃) ) kom maj mam hloov cov hardness ntau dhau mus rau hauv cov qauv tempered ntau dua los tiv thaiv kev tawg tawg thaum siv.
3.2 Cov txheej txheem quenching
Qhov tseem ceeb ntawm quenching muaj xws li austenitization thiab ceev txias. Siab - lub zog bolts yuav tsum muaj tsawg kawg yog 90% ntawm cov tub ntxhais los hloov mus rau hauv martensite kom tau raws li qhov yuav tsum tau muaj zog thiab toughness qauv. Hauv kev tsim khoom tiag tiag, lub sijhawm cua sov thiab tuav lub sijhawm yuav tsum tau tswj raws li txoj kab uas hla ntawm lub ntsia liaj qhov rooj, cov khoom muaj pes tsawg leeg thiab cov uniformity ntawm lub cub tawg kub. Yog tias lub sijhawm cua sov tsis txaus lossis qhov txias txias qeeb dhau, cov tub ntxhais yuav khaws pearlite lossis lwm yam qis - cov qauv muaj zog, ua rau cov khoom siv tsis zoo.
3.3 Tempering txheej txheem
Rau siab -lub zog bolts, siab zoo - kub tempering (feem ntau nyob rau hauv thaj tsam ntawm 500-650 degree) yog qhov tseem ceeb tshwj xeeb. Lub luag haujlwm tseem ceeb ntawm tempering muaj xws li:
Relieve thermal stress: Thaum lub sij hawm ceev ceev ntawm quenching txheej txheem, qhov loj kub gradient nyob rau hauv lub ntsia liaj qhov rooj yuav ua rau muaj kev ntxhov siab nyob rau hauv ntau dua. Yog tias tempering tsis ua, cov kab nrib pleb yuav tshwm sim thaum siv tom ntej.
Stabilize tus qauv thiab qhov loj me: Tempering hloov ib qho me me ntawm cov seem austenite rau hauv martensite, rov faib cov carbide precipitates hauv martensite kom sib npaug, yog li txhim kho toughness thiab stabilizing qhov loj.
Txo brittleness: Martensite nyob rau hauv siab - lub zog yog feem ntau nkig; tempering tuaj yeem tsim tempered troostite lossis tempered troostite, uas muab zoo dua toughness thiab ductility.
3.4 Kev xav txog kev kho cua sov
Rauv qhov kub thiab txias tsis sib xws: Txawm hais tias siv lub thawv rauv los yog ntau- lub hom phiaj lub qhov cub, qhov kub ntawm txhua qhov chaw cua sov yuav tsum zoo ib yam kom ntseeg tau tias kev hloov pauv microstructural zoo ib yam thoob plaws hauv lub bolt.
Kev tswj cov pa roj carbon monoxide: Rau cov ntaub ntawv uas xav tau carburization los yog carbon retention, tswj cov pa roj carbon muaj peev xwm thiab cov pa oxygen sojntsuam yog qhov tseem ceeb los tiv thaiv decarburization lossis cov pa roj carbon ntau.
Nto thiab core hardness faib: Rau cov bolts loj, tshwj xeeb yuav tsum tau them nyiaj rau qhov sib txawv ntawm cov cua txias ntawm cov tub ntxhais thiab qhov chaw. Cov tub ntxhais txias tsis txaus yuav ua rau pearlite lossis bainite qauv, uas cuam tshuam rau tag nrho lub zog.
Tsis txhob hydrogen embrittlement: Thaum lub sij hawm pickling, electroplating los yog phosphating, hydrogen atoms yuav nkag mus rau hauv cov hlau thiab ua rau hydrogen embrittlement. Txhawm rau daws qhov teeb meem no, dehydrogenation tempering ntawm 190-230℃feem ntau yog ua tom qab kho saum npoo.
Yog tias koj xav kawm ntxiv txog kev kho cua sov, koj tuaj yeem saib cov yeeb yaj kiab ntawm Metallurgical Data Channel.
4. Kev tshuaj xyuas zoo thiab kev yuav khoom ntawm siab - lub zog bolts
4.1 Kev xeem ua haujlwm
Cov khoom siv tshuaj ntsuam xyuas rau siab - lub zog bolts yog:
Tensile test: ntsuas lub zog tensile, tawm lub zog, elongation, hla -sectional txo (Z tus nqi) thiab lwm yam ntsuas los xyuas kom meej raws li ASTM A490, A354 thiab lwm yam qauv.
Hardness test: Rockwell hardness (HRC) lossis Brinell hardness (HB) feem ntau yog siv los ntsuas qhov zoo ntawm kev kho cua sov.
Kev ntsuam xyuas kev cuam tshuam: Rau cov ntsia hlau uas xav tau qis- qhov kub thiab txias, xws li bolts siv hauv cua fais fab, marine engineering lossis siab - qhov chaw txias, Charpy cuam tshuam qhov ntsuas yuav tsum tau nyob ntawm -20 degree, -40℃lossis qis dua kom ntseeg tau tias cov bolts tsis tawg hauv qhov chaw txias.
Metallographic tsom xam: saib xyuas qhov microstructure ntawm ntu ntu ntawm lub ntsia liaj qhov rooj (kos martensite, bainite, ferrite, grain roughness, thiab lwm yam) los ntsuas qhov zoo ntawm kev kho cua sov thiab cov khoom sib xws.
Kev kuaj pom qhov tsis xws luag: tshawb xyuas cov kab nrib pleb, quav, decarburization nto lossis lwm yam tsis xws luag hauv cov xov, taub hau lossis pas nrig.
Yog tias koj xav paub ntau ntxiv txog kev tshuaj xyuas cov ntsia hlau zoo, koj tuaj yeem nyeem tsab xov xwm "Qhia rau Cov Txheej Txheem Tag Nrho Cov Ntsiab Cai Kev Ntsuam Xyuas Zoo".
4.2 Standardization thiab Certification
Cov ntawv pov thawj thoob ntiaj teb lossis cov qauv tsim pab cov neeg yuav khoom sai sai ntsuas qhov kev ntseeg tau thiab ua raws li cov khoom lag luam. Cov ntawv pov thawj thiab cov qauv muaj xws li:
TS EN ISO 898-1 Cov cuab yeej cuab tam ntawm Bolts
TS EN ISO 6157 Cov Lus Cog Tseg rau Kev Tshawb Fawb Txog Kev Ua Haujlwm Ntawm Qhov Chaw
Cov qauv tshwj xeeb rau cov chaw sib txawv xws li ASTM A193 / A320 / A354 / A490
ISO 9001 Daim Ntawv Pov Thawj Zoo
Cov neeg tsim khoom nrog cov ntawv pov thawj no thiab cov kev sim ua tiav feem ntau muaj kev tswj hwm kev tsim khoom thiab kev tswj xyuas kom zoo los xyuas kom meej qhov sib xws hauv cov khoom siv batch.
4.3 Cov lus pom zoo rau kev yuav khoom rau siab -Lub zog Bolts
Tshem tawm ib puag ncig kev siv thiab cov kev xav tau: Qhia qhov chaw siv (qhov kub thiab txias, ib puag ncig corrosive, cuam tshuam rau kev thauj khoom) ua ntej yuav khoom, thiab muab qhov tseem ceeb rau cov ntsuas kev ua tau zoo (xws li lub zog tensile, cuam tshuam toughness).
Xaiv ib lub chaw tsim khoom lag luam uas ntseeg tau: Kev tsim cov siab - lub zog bolts yuav tsum tau siab - cov ntaub ntawv zoo, khoom siv thiab cov txheej txheem. Nws raug nquahu kom xaiv cov chaw tsim khoom nrog cov kab ntau lawm, kev tswj xyuas nruj thiab kev siv thev naus laus zis kom txo tau qhov kev pheej hmoo ntawm kev teeb tsa thiab kev saib xyuas tom qab.
Kev tshuaj xyuas cov ntaub ntawv thiab cov txheej txheem kho cua sov: Paub meej nrog cov neeg muag khoom cov khoom lag luam raw khoom, cov ntaub ntawv txheeb xyuas cov khoom muaj pes tsawg leeg, txoj kev kho cua sov (tempering kub, quenching nruab nrab, thiab lwm yam), thiab daim ntawv qhia kev ua tau zoo los xyuas kom meej cov khoom sib xws.
Kev sim thiab ntsuas: Rau cov haujlwm uas muaj qhov hnyav hnyav lossis muaj kev pheej hmoo siab, xav txog kev sim ua cov khoom me me lossis kev soj ntsuam random ua ntej loj - kev yuav khoom loj kom txo qis qhov pheej hmoo.
Customization yuav tsum tau: Yog tias tshwj xeeb siab - lub zog bolts lossis bolts siv nyob rau hauv ib puag ncig tshwj xeeb (xws li qis- qhov kub thiab txias hauv qab -40℃, qhov kub thiab txias ib puag ncig corrosion siab) yuav tsum, koj tuaj yeem sib txuas lus nrog cov chaw tsim khoom los kho cov alloy muaj pes tsawg leeg lossis cov phiaj xwm kho cua sov kom tau raws li qhov xav tau tiag tiag.