Automated Silver Electrical Riveted Cheebtsam thiab vuam cov rooj sib txoos yuav tsum muaj kev siv tshuab nruj kom tiv thaiv kev tiv thaiv kev sib cuag, kev tiv thaiv ntau dhau, thiab kev yaig ntxov ntxov hauv high-voltage DC contactors thiab Circuit Court breakers. Yuav kom ua tau raws li IATF 16949 tus qauv, kev tsim khoom ua tau zoo yuav tsum muaj kev tswj xyuas meej ntawm cov txheej txheej nyiaj, micro-hardness gradients, thiab txhua yam shear lub zog siab dua 150 MPa kom ntseeg tau tias muaj kev ntseeg siab hla 100, 000+ hluav taws xob hloov mus raws li IEC 60947 kev ua haujlwm.
Kev Sib Txuas Nyiaj Sib Txuas Tsis Txaus Siab: IEC 60947 thiab Kev Ntsuas Shear
Rau automated silver contact riveted thiab welded assemblies, kev sib koom ua ke yuav tsum tau xyuas kom meej ntawm kev sib cuag -rau -carrier interface, tsis tsuas yog los ntawm kev soj ntsuam pom. Lub hom phiaj tswj kev tsim khoom yuav tsum sib cuam tshuam lub zog shear, tiv thaiv kev tiv thaiv, metallographic bonding, nyiaj - txheej thickness, qhov ntev ntev, thiab cov txheej txheem traceability nrog cov hluav taws xob yuav tsum tau ua tiav ntawm relay tiav, contactor, breaker, los yog switching device.
Cov txheej txheem tsis ua haujlwm tseem ceeb yog kev sib cais ntawm cov tshuab sib cais, qhov chaw sib txuas tsis txaus, kev tiv thaiv ntau dhau, nyiaj- txheej delamination, eccentric riveting, weld exulsion, tawg ntawm tshav kub- thaj tsam cuam tshuam, thiab deformation ntawm cov cab kuj.
Rau relay thiab qis -voltage switching Cheebtsam, kev tiv thaiv tiv thaiv yuav tsum tau ntsuas raws li kev ntsuas tam sim no, kev sib cuag quab yuam, lub sijhawm ruaj khov, thiab ib puag ncig. Tus nqi milliohm yam tsis muaj nws txoj kev xeem tsis txaus rau tus neeg tsim khoom tsim nyog.
Kev sim tshuab yuav tsum sib txawv ntawm rivet taub hau rub-tawm, shear loading, torsional loading, thiab carrier deformation. Ib qho shear - tus lej quab yuam tsis tuaj yeem sawv cev rau txhua qhov kev sib koom ua ke.
AgSnO2 thiab AgNi Cov ntaub ntawv tiv tauj: IEC 60947 Hluav taws xob cov dej num
AgSnO2 thiab AgNi raug xaiv raws li hluav taws xob load, hloov zaus, arc tej yam kev mob, tiv tauj quab yuam, thiab yuav tsum tau ua hauj lwm rau vuam los yog yaig.
| Khoom siv | Hom muaj pes tsawg leeg | Main engineering yam ntxwv | Common kev xav |
|---|---|---|---|
| AgSnO2 | Ag/SnO2, eg. 88/12 | Arc yaig thiab vuam tsis kam | Relay, contactor thiab hloov daim ntawv thov |
| AgNi | Ag/Ni, muaj pes tsawg leeg sib txawv | Tus cwj pwm kev sib cuag ruaj khov nyob rau hauv cov ntaub ntawv teev tseg | Relays thiab hloov khoom siv |
| Pure Ag | Ntau dua lossis sib npaug rau 99.9% Ag nyob ntawm qib | High hluav taws xob conductivity | Cov ntawv thov tsis tshua muaj siab |
| Ag alloy hu rau Cu carrier | Silver alloy + tooj liab substrate | Txo cov nqi-hlau noj | Riveted hluav taws xob sib dhos |
Qhov tseeb AgSnO2 piv, particle qauv, hardness, thiab kev tsim khoom yuav tsum tau teev nyob rau hauv cov ntaub ntawv pov thawj es inferred los ntawm cov khoom npe.
Rivet Joint Defects: ± 0.02 hli Geometry thiab Interface Control
Cov kev tsis xws luag muaj xws li:
- Eccentric rivet sib sau ntawm ± 0.02-0.05 hli qhov ntev tswj
- Tsis txaus siab qhov siab tshwm sim los ntawm cov khoom ntim tsis raug
- Cracking los ntawm txias heev - taub hau deformation
- Cov nyiaj tsis tiav - rau - kev sib txuas ntawm cov cab kuj
- Xaws lub taub hau tom qab sib sau
- Ntau burrs cuam tshuam rau relay sib dhos
- Tiv tauj misalignment ua rau tsis sib xws hluav taws xob loading
- Lub zos deformation ntawm stamped BeCu los yog tooj liab nqa
Cov txheej txheem tsis xws luag yog feem ntau cuam tshuam nrog kev sib xyaw ntawm cov khoom siv hardness, qhov khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob khoob
Rau cov kab automated, kev tshuaj xyuas qhov ntev yuav tsum tau txuas nrog cov txheej txheem parameter cov ntaub ntawv. Yog hais tias txoj kab uas hla ntawm kev sib cuag tseem nyob rau hauv lub siab ntev, tab sis qhov sib koom shear lub zog poob, qhov kev soj ntsuam ib leeg yuav tsis txheeb xyuas qhov laj thawj.
Thov Kev Ntsuam Xyuas DFM Dawb & Tso Cai
Hauv -Tuag Riveting vs Resistance thiab Ultrasonic Vuam: IEC 60947 Kev Sib Koom Tes
Cov txheej txheem sib koom ua ke txiav txim siab yuav ua li cas cov khoom tuav tswj, hluav taws xob txuas ntxiv, cov khoom siv hluav taws xob, thiab cov khoom rov ua kom tiav. Nyob rau hauv - tuag riveting, kuj welding, thiab ultrasonic vuam yuav tsum yog li ntawd yuav tsum tau soj ntsuam los ntawm kev sib koom geometry thiab hluav taws xob lub luag hauj lwm es tsis kho raws li interchangeable txheej txheem.
| Txoj kev koom nrog | Mechanical koom nrog mechanism | Kub input | Kev tshuaj ntsuam xyuas kom pom tseeb | Kev xav txog kev tsim khoom |
|---|---|---|---|---|
| Nyob rau hauv tuag riveting | Yas deformation thiab mechanical interlock | Tsawg heev ntawm kev sib koom ua ke | Rivet geometry, shear force, cross-section | High-speed progressive ntau lawm |
| Kuj welding | Localized Joule cua sov thiab fusion/bonding | Siab tab sis localized | Nugget, tam sim no, quab yuam, weld splash | Haum rau kev txiav txim siab conductive sib dhos |
| Ultrasonic vuam | High-frequency mechanical vibration | Cov cua kub tsawg heev | Bond cheeb tsam, amplitude, siab | Siv tau rau cov kev xaiv conductive interfaces |
| Brazing | Filler-hlau metallurgical daim ntawv cog lus | Tswj thermal voj voog | Wetting, voids, sib koom thickness | Haum rau qhov yuav tsum tau muaj kev sib koom ua ke metallurgical |
Hauv -Kev Tuag Riveting: Kev Tswj Xyuas Kev Tuag ntawm Cov Nqi Ntau Lawm
Nyob rau hauv - tuag riveting integrates kev sib cuag pub noj, carrier positioning, tho, sib sau, thiab soj ntsuam mus rau ib tug tswj ntau lawm kab. Cov txheej txheem tuaj yeem txo qhov kev hloov pauv vim tias txoj haujlwm sib cuag tau tsim nyob rau hauv lub stamping lossis cov cuab yeej tsim.
Cov kev hloov pauv tseem ceeb muaj xws li:
- Feed pitch precision:feem ntau tswj tau raws li qhov yuav tsum tau kos duab
- Rivet shank txoj kab uas hla:Feem ntau tswj tsis pub dhau ± 0.02-0.05 hli
- Tuag clearance:txhais raws li cov khoom thickness thiab hardness
- Txoj kev mob stroke:tswj kom tsis txhob nyob rau hauv -forming los yog tshaj -forming
- Rivet taub hau qhov siab:ntsuas los ntawm optical los yog laser soj ntsuam
- Hu rau center txoj hauj lwm:txheeb xyuas tawm tsam tus cab kuj datum
- Tool hnav:saib xyuas los ntawm qhov seem drift thiab quab yuam kos npe
Lub ntsiab engineering kom zoo dua tsis yog kev ceev xwb. Nws yog qhov txo qis ntawm qhov chaw hloov pauv ntawm cov khoom thauj khoom thiab cov khoom sib cuag.
Resistance Welding: Tam sim no, Force thiab Nugget Metallography
Kev ua haujlwm vuam zoo nyob ntawm kev sib cuam tshuam ntawm vuam tam sim no, qhov hluav taws xob, hluav taws xob hluav taws xob, lub sijhawm vuam, kev sib cuag, cov khoom tsis kam, thiab electrode geometry.
Rau kev tsim khoom validation, vuam specification yuav tsum txhais:
- Vuam tam sim no lossis lub zog ntau yam
- Electrode quab yuam
- Weld lub sijhawm
- Electrode geometry
- Tus naj npawb ntawm pulses
- Tuav lub sijhawm
- Kev tshem tawm siab kawg nkaus
- Yam tsawg kawg nkaus nugget lossis thaj chaw sib koom ua ke
- Kev puas tsuaj ntau zaus
- Metallographic txais cov qauv
Ib qho kev sib txuas uas dhau los ntawm kev tshuaj xyuas qhov muag tseem tuaj yeem muaj cov fusion tsis txaus lossis muaj qhov tsis txaus sab hauv. Metallographic sectioning yog li tseem muaj txiaj ntsig zoo thaum lub sijhawm ua haujlwm raug cai thiab tshawb xyuas lub sijhawm.
Ultrasonic Vuam: Amplitude, Siab thiab Bond Area
Ultrasonic welding generates kev sib txhuam txav ntawm lub interface nyob rau hauv kev tswj siab. Rau cov khoom siv hluav taws xob, lub qhov rais txheej txheem yog nyob ntawm cov khoom hardness, qhov chaw ntawm qhov chaw, hu rau geometry, kev vibration amplitude, weld lub sij hawm, thiab siv zog.
Tsis zoo li cov welding kuj, ultrasonic vuam tsis cia siab feem ntau ntawm cov hluav taws xob tiv thaiv cua sov. Qhov no hloov cov thermal raug ntawm cov khoom nyob ib puag ncig.
Cov txheej txheem kev tsim nyog yuav tsum sib txheeb:
| Hloov pauv | Tswj lub hom phiaj |
|---|---|
| Amplitude | Tswj interfacial mechanical zog |
| Weld quab yuam | Tswj lub interface siab |
| Weld lub sijhawm | Txiav txim siab lub zog nkag |
| Ua zog | Txhais cov txheej txheem pib |
| Tuav lub sijhawm | Stabilizes kev sib raug zoo interface |
| Bond cheeb tsam | Txiav txim siab txoj kev coj zoo |
| Hla ntu | Paub meej interface txuas ntxiv |
Rau nyias tooj liab, nyiaj, los yog tooj liab- alloy Cheebtsam, lub zog ultrasonic ntau dhau tuaj yeem ua rau hauv zos thinning, deformation deformation, lossis tawg. Cov teebmeem no yuav tsum raug kuaj xyuas los ntawm kev puas tsuaj hla -section tsom xam.
Joint Strength thiab Metallography: ASTM B117, ISO 9001 thiab IATF 16949 Tswj
Ib tus neeg tsim nyog tau txais kev sib cuag nyiaj yuav tsum tsis txhob tso ntau ntau ntau raws li kev tshuaj xyuas kom zoo nkauj. Mechanical, hluav taws xob, metallurgical, thiab cov yam ntxwv ntawm qhov ntev yuav tsum tau txuas nrog los ntawm cov ntaub ntawv tswj kev npaj.
Shear Strength: Txhais Load Direction thiab Failure Hom
Kev ntsuam xyuas shear yuav tsum qhia meej fixture geometry, loading direction, crosshead speed, support condition, sample orientation, and failure classification.
Ib tus neeg siv khoom tuaj yeem hais qhia qhov yuav tsum tau muaj xws li lub zog shear Ntau dua lossis sib npaug ntawm 150 MPa, tab sis tus nqi no yuav tsum tsis txhob raug xa mus ntawm qhov sib txawv geometries yam tsis muaj engineering validation.
Hom kev ua tsis tiav yog qhov tseem ceeb sib npaug:
| Ua tsis tiav hom | Txhais lus |
|---|---|
| Tiv tauj cov khoom tawg | Tiv tauj cov ntaub ntawv lub zog tej zaum yuav txwv |
| Interface sib cais | Bonding lossis koom txheej txheem yuav tsum tau tshawb xyuas |
| Rivet taub hau deformation | Kev tsim cov geometry lossis cov khoom ntim yuav tsis txaus |
| Carrier kua muag | Cov khoom nqa khoom lossis cov duab geometry tuaj yeem txwv |
| Weld nugget tawg | Vuam lub zog los yog qhov chaw sib txuas yuav xav tau kev tshuaj xyuas |
| Ib nrab interface sib cais | Muaj peev xwm kis kab mob hauv zos lossis tsis sib xws |
Rau kev puas tsuaj, qhov chaw tawg yuav tsum tau sau ua ke nrog lub zog siab tshaj plaws.
Metallographic Hla-Section: Void, Crack thiab Bond-Kev tshuaj xyuas cheeb tsam
Metallography yog qhov tshwj xeeb tshaj yog rau kev paub qhov txawv ntawm qhov tsis xws luag los ntawm qhov tsis xws ntawm metallurgical.
Tus ntoo khaub lig-section tuaj yeem nthuav tawm:
- Nyiaj - txheej thickness
- Hu rau -rau- tus neeg nqa khoom interface
- Intermetallic lossis diffusion cheeb tsam uas muaj feem xyuam
- Weld nugget dimensions
- Internal voids
- Kev tawg
- Delamination
- Cov khoom ntws tom qab txias taub hau
- Stamping -induced deformation
- Local thinning
- Plating interface mob
Cov txheej txheem kev npaj tus neeg sawv cev tuaj yeem suav nrog ntu ntu, txuas, sib tsoo, polishing, etching qhov twg siv tau, kho qhov muag microscopy, thiab cov ntaub ntawv duab.
Nyiaj - Txheej thiab Plating Thickness: XRF thiab Hla -Kev Tshawb Fawb Ntu
Nyiaj - txheej thickness yuav tsum tau ntsuas raws li kev tsim kho ntawm kev sib cuag.
Rau cov khoom plated, XRF tuaj yeem muab kev tshuaj ntsuam xyuas tsis zoo sai sai, thaum metallographic cross-section tsom xam muab ntsuas lub cev ncaj qha.
Rau kev sib cuag bimetal, cov nyiaj tuab yog ib feem ntawm cov ntaub ntawv sib cuag geometry es tsis yog cov txheej txheem electroplated. Txoj kev tshuaj xyuas yuav tsum yog li ntawd sib phim rau kev tsim kho.
Cov khoom lag luam zoo specification yuav tsum txheeb xyuas:
- Silver alloy qib
- Silver txheej thickness los yog ntim
- Copper substrate qib
- Interface mob
- Dimensional kam rau ua
- Txoj kev ntsuas
- Sampling zaus
- Kev txheeb xyuas ntau
Cov kab lus "kev sib cuag nyiaj" ib leeg tsis txhais cov ntsiab lus nyiaj, alloy muaj pes tsawg leeg, txheej tuab, lossis hluav taws xob ua haujlwm.
Corrosion thiab Environmental Testing: ASTM B117 thiab IEC 60947
Ntsev-kev tshuaj ntsuam tshuaj raws li ASTM B117 tuaj yeem siv los ntsuas qhov kev tiv thaiv corrosion ntawm cov plated haum lossis raug-cov khoom siv hlau. Txawm li cas los xij, ASTM B117 cov txiaj ntsig tshwm sim yuav tsum tsis txhob raug txhais raws li qhov chaw ncaj qha - kev kwv yees lub neej.
Rau cov khoom siv hluav taws xob qis qis, IEC 60947 yuav tsum tau txiav txim siab ua ke nrog cov khoom siv tiag tiag, cov khoom siv hluav taws xob, kev ua haujlwm ib puag ncig, kub, av noo, thiab lub luag haujlwm ntawm lub tshuab.
Tham nrog peb cov kws tsim hluav taws xob niaj hnub no
Kev soj ntsuam tsis siv neeg: ± 0.005 hli Kev ntsuas thiab txheej txheem Traceability
Automation txhim kho kev tswj kom zoo thaum ntsuas cov ntaub ntawv txuas nrog cov txheej txheem sib txawv. Lub koob yees duab uas pom qhov kev sib cuag uas ploj lawm yog qhov muaj txiaj ntsig zoo, tab sis cov txheej txheem tsim khoom muaj peev xwm ntawm kev sib txuas ntawm txoj haujlwm, rivet qhov siab, tsim quab yuam, vuam tam sim no, tsis kam, thiab ntau traceability muab cov txheej txheem muaj zog ntau dua.
Kev tshuaj xyuas lub zeem muag: ± 0.005 mm Dimensional Verification
Siab -Kev daws teeb meem kho qhov muag tuaj yeem siv rau cov yam ntxwv geometric tseem ceeb uas cov khoom kos duab tso cai ntsuas qhov muag.
Tej yam tshuaj ntsuam xyuas muaj xws li:
- Tiv tauj nrog
- Hu rau kev taw qhia
- Rivet taub hau taub
- Rivet taub hau qhov siab
- Hu rau lub chaw haujlwm
- Carrier profile
- Burrs
- Qhov chaw paug
- Tsis muaj lossis ob npaug - noj cov khoom xyaw
- Stamping deformation
Ib qho kev kam rau ua xws li ± 0.005 hli yuav tsum tau txuas mus rau qhov tseeb kos duab datum qauv thiab ntsuas qhov muaj peev xwm. Nws yuav tsum tsis txhob muab nthuav tawm raws li universal kam rau ua rau txhua txhua stamped contact los ua ke.
Kev Ntsuas Hluav Taws Xob Hauv Hluav Taws Xob: Tiv tauj tiv thaiv hauv mΩ
Kev ntsuas hluav taws xob tiv thaiv tuaj yeem txheeb xyuas cov txheej txheem drift uas tsis tuaj yeem pom los ntawm kev tshuaj xyuas qhov muag.
Kev ntsuas ntsuas qhov system yuav tsum txhais:
- Kuaj tam sim no
- Kev ntsuas voltage
- Tshawb xyuas lub zog
- Tshawb xyuas qhov chaw
- Lub sijhawm ruaj khov
- Kub
- Pass / poob qhov pib
- Kev ntsuas repeatability
Piv txwv li, yog tias tus neeg siv khoom tshwj xeeb xav tau kev tiv thaiv qis dua lossis sib npaug li 1 mΩ, qhov ntsuas qhov ntsuas thiab ntsuas tam sim no yuav tsum muaj peev xwm daws qhov nqi nrog kev rov ua kom txaus.
Kev tiv thaiv tiv thaiv yuav tsum tau saib xyuas raws li kev txheeb cais es tsis yog tsuas yog kuaj ntawm qhov kev tshuaj ntsuam zaum kawg.
SPC thiab IATF 16949: Txheej Txheem Muaj Peev Xwm Ua Ntej Tshaj Tawm
Rau automotive lossis EV-cov ntawv thov ntsig txog, cov txheej txheem kev tshawb fawb muaj peev xwm tuaj yeem siv rau qhov loj me thiab kev sib koom ua ke.
Cov kev tswj xyuas ib txwm muaj xws li:
- Cp/Cpk tsom xam
- X-bar/R lossis cov kab kos uas tsim nyog
- Thawj - daim ntawv pom zoo
- Cov cuab yeej- saib xyuas lub neej
- Kev ntsuas - kev tshuaj xyuas qhov system
- Ntau traceability
- Tsis yog - ua raws li cov khoom sib cais
- Kho -cov ntaub ntawv ua
IATF 16949 muab qhov zoo tshaj - kev tswj lub moj khaum uas nquag siv los ntawm cov khoom siv tsheb. Cov neeg siv khoom- cov kev cai tshwj xeeb tseem tsim nyog vim tias muaj ntawv pov thawj rau kev tswj hwm- tus qauv txheej txheem tsis tsim cov kev txwv kev lees paub rau ib qho kev sib cuag nyiaj.
Automated Defect txo: Cov txheej txheem tawm tswv yim dua li qhov kawg sorting
Automation txo qhov tsis xws luag khiav tawm tau zoo tshaj plaws thaum kuaj xyuas cov txiaj ntsig pub rov qab rau hauv kev tsim lossis kev koom ua ke.
Ib qho raug kaw- lub voj voj voog yog:
Cov ntaub ntawv ntau ntau → pub → stamping → kev sib cuag → riveting / vuam → seem soj ntsuam → hluav taws xob soj ntsuam → cov ntaub ntawv txiav → SPC tsom xam → txheej txheem hloov
Txoj hauv kev no tso cai rau cov kws tsim khoom tsim khoom los txheeb xyuas qhov drift ua ntej qhov ntau ntawm cov rooj sib txoos mus txog qhov kev tshuaj ntsuam zaum kawg.
Rau siab - ntim ntau lawm, kev soj ntsuam zaus tuaj yeem muab faib ua:
| Kev tshuaj xyuas theem | Hom hom phiaj |
|---|---|
| Thawj tsab xov xwm | Paub meej tias cov cuab yeej thiab txheej txheem teeb tsa |
| Kev tshuaj xyuas pib | Paub meej tias thawj zaug kev ruaj ntseg |
| Nyob rau hauv-txoj kev sampling | Tshawb pom qhov ntev / txheej txheem drift |
| 100% kev soj ntsuam tsis pom kev | Txheeb xyuas qhov muaj nyob, kev taw qhia, thiab pom tseeb geometry defects |
| Kev kuaj hluav taws xob lossis 100% kuaj | Txheeb xyuas qhov kev xav tau ntawm kev tiv thaiv |
| Kev puas tsuaj sampling | Txheeb xyuas qhov sib koom ua ke lub zog thiab kev mob metallurgical |
| Kev tshawb xyuas zaum kawg | Paub meej tias traceability thiab tso cov ntaub ntawv |
Cov lus nug nquag
Dab tsi yog qhov tsawg kawg nkaus shear zog yuav tsum tau rau automated silver contact riveting assemblies?
Automated silver contact riveting assemblies yuav tsum tiv taus qhov tsawg kawg nkaus shear zog ntawm 150 MPa los tiv thaiv cov neeg kho tshuab detachment nyob rau hauv tas li high-frequency electromagnetic actuation nyob rau hauv relays thiab Circuit Court breakers.
Xiamen Apollo Electric Co., Ltd yuav ua li cas kom ntseeg tau cov ntaub ntawv traceability rau cov nyiaj tiv tauj cov khoom?
Cov ntaub ntawv traceability yog tswj los ntawm nruj IATF 16949 ntau-tswj raws tu qauv, txuas raw khoom zeb xeem daim ntawv pov thawj (spectrochemical muaj pes tsawg leeg tsom xam rau AgSnO2, AgCdO, los yog AgNi) ncaj qha rau laser-etched batch tooj ntawm zaum kawg ntim.
Tus qauv coj mus kuaj lub sij hawm rau kev cai-engineered hu rau vuam sib dhos yog dab tsi?
Tus qauv qauv thiab qauv tsim rau kev cai bimetal rivets, stamped hniav, thiab welded sib txuas cov rooj sib tham feem ntau yuav tsum tau 10 mus rau 15 hnub ua hauj lwm, txhawb los ntawm tag nrho cov seem soj ntsuam cov ntaub ntawv thiab cov khoom cross-section micrographs.
tiv tauj peb
Rau ib tug tshiab los yog hloov nyiaj hu rau vuam los ua ke los yoghauv - tuag riveting hluav taws xob tiv tauj, muab 2D daim duab, 3D qauv, cov ntaub ntawv tiv tauj, cov khoom thauj khoom, hluav taws xob thauj khoom, lub hom phiaj tiv thaiv, sib koom ua ke - lub zog yuav tsum tau, ntim txhua xyoo, thiab siv tau IEC 60947 lossis cov neeg siv khoom tshwj xeeb. Kev tshuaj xyuas engineering tuaj yeem txheeb xyuas cov txheej txheem kev koom ua ke, kev tshuaj ntsuam xyuas, kev xav tau ntawm cov cuab yeej, thiab kev tsim khoom- tswj tsis tau ua ntej hais.
