Xaiv cov chaw tsim khoom ntawm lub tshuab sealing hauv qab yog qhov tseem ceeb rau kev txiav txim siab. Cov khoom siv cuam tshuam rau lub sijhawm tsim khoom, khib nyiab zaj duab xis, foob zoo thiab thaum kawg ntim zoo. Tsis zoo li sab lossis peb -sided sealing tshuab, hauv qab sealing tshuab muaj lub hnab ntim tiaj tiaj thiab lub zog sealing siab. Lawv feem ntau yog siv rau hauv cov hnab ntim khoom noj, ntim khoom kho mob thiab lub hnab ntim khoom hnyav. Tsawg- cov tshuab ua tau zoo tuaj yeem ua rau cov dej xau, cov foob tsis sib xws thiab raug nqi ntau lawm. Xaiv txoj cai hauv qab lub hnab sealing tshuab yuav tsum muaj kev soj ntsuam zoo ntawm ob qho tib si kev ua haujlwm thiab tom qab- kev txhawb nqa muag.
Phau ntawv qhia no muab ib txoj hauv kev yooj yim thiab meej ntawm kev ntsuam xyuas tus neeg muag khoom. Nws txais yuav cov kev coj ua, cov qauv kev ntseeg siab ntawm lub tshuab thiab kev kuaj xyuas lub Hoobkas. Nws tsis tsom rau kev tsim khoom lag luam lossis kev tshaj tawm. Nws muab cov ntsiab lus tswv yim uas cov neeg yuav khoom siv tau thaum xaiv cov neeg muag khoom.
Kauj Ruam 1: Txiav txim siab koj qhov profile ntau lawm ua ntej hu rau koj tus neeg muag khoom
Ntau tus neeg yuav khoom tau hu rau cov tuam txhab tsis tau npaj nrog cov kev cai tshwj xeeb. Qhov no tuaj yeem ua teeb meem. Cov neeg tsim lub hnab hauv qab tsis haum rau txhua daim ntawv thov. Koj yuav tsum tau txhais cov hauv qab no:
Hom Zaj duab xis-LDPE, HDPE, PP, laminated multilayer lossis biodegradable? Txhua yam khoom yuav tsum muaj qhov sib txawv ntawm qhov kub thiab txias (feem ntau yog 120℃-200 degree) thiab lub sijhawm sib khi.
Lub hnab loj- qhov tsawg kawg nkaus thiab siab tshaj qhov dav thiab ntev ntawm lub hnab. Qee lub tshuab tuaj yeem muaj qhov dav ntawm 100-600 hli, thaum lub tshuab hnyav tuaj yeem muaj qhov dav ntawm 1,200 hli.
Foob thickness-Lub foob hauv qab feem ntau yuav tsum yog 5-15 mm dav. Thicker seals yuav tsum tau sealing siab dua (hauv Newtons) thiab lub sijhawm txias dua.
Kev nrawm nrawm-Kev nrawm nrawm yog feem ntau 40-180 sacks ib feeb. Kev nrawm dua feem ntau xav tau cov tshuab servo-tsav ntau dua li cov tshuab pneumatic.
Foob tus qauv zoo-Koj puas yuav siv ASTM F88 lossis ISO 527-3 raws li kev kuaj tawv nqaij, kuaj tawg lossis kuaj tshuaj zas? Cov chaw tsim khoom yuav tsum kho lub tshuab kom ua tau raws li cov cai no.
Npaj ib daim ntawv - nplooj ntawv kev xav tau ua ntej hu rau tus neeg muag khoom. Qhov no yuav pab tshem tawm cov khoom lag luam uas tsuas yog tsim cov tshuab txheem thiab pab koj nrhiav cov tuam txhab uas tuaj yeem kho cov hnab ntim hauv qab rau koj cov khoom siv zaj duab xis thiab cov kev xav tau ntau lawm.
Kauj Ruam 2: Tshawb xyuas cov Chaw Tsim Khoom Siv Kho Kom Zoo
Ib tus neeg muag khoom ntseeg siab lub Hoobkas qhia cov ntaub ntawv ntau dua li lawv cov khoom muag. Cov ntsiab lus hauv qab no yuav tsum raug sau tseg thaum kuaj xyuas cov chaw tsim khoom ntawm lub hauv paus sealing tshuab: Cov txheej txheem kev ncaj ncees ntawm lub hnab ntim hauv qab ua tshuab txiav txim siab nws qhov ntev - lub sij hawm sealing zoo ib yam thiab kev ua haujlwm ruaj khov.
A. Ncej zog thiab kev co tswj
Rov ua dua -thiab- kev txav ntawm lub puab tsaig kaw ua rau muaj kev cuam tshuam tsis tu ncua. Hnyav-lub luag haujlwm cam khwb cia hlau los yog welded lub thawv thav duab tsim (nrog rau phab ntsa tsawg kawg yog 12 hli tuab) txo kev vibration thiab pab foob rods kom txawm sib cuag nrog zaj duab xis. Nug tus neeg muag khoom: "Dab tsi yog qhov zaus ntawm koj lub thav duab thiab nws phim koj lub tshuab ua haujlwm ceev li cas?" Yog tias lawv tsis tuaj yeem muab cov lus teb, xav txog lwm tus neeg muag khoom. Raws li VDI 3830 tshuab dynamics cov lus qhia, ncej deformation yuav tsum tsawg tshaj li 0.05 hli / m ntawm tag nrho cov load.
B. Foob lub puab tsaig khoom thiab tswj qhov kub thiab txias
Hauv qab sealing lub puab tsaig feem ntau yog ua los ntawm txhuas lossis tooj dag thiab coated nrog PTFE. Siab- cov tuam txhab lag luam zoo yuav siv beryllium tooj liab inlays kom ceev cov cua sov hloov thiab txhim kho kev puas tsuaj. Qhov tseem ceeb tshaj, nug txog qhov kub thiab txias faib thoob plaws hauv lub puab tsaig sealing. Cov neeg muag khoom ntseeg siab yuav tsum muab cov ntaub ntawv qhia txog kev siv hluav taws xob infrared uas qhia qhov kub thiab txias tsis pub dhau + -2℃. Cov cua kub tsis sib xws ua rau muaj qhov tsis muaj zog sealing, uas kuj yog ib qho ua rau muaj kev ua haujlwm tsis zoo thaum siv hnab ntaub.
C. Tsav System Xaiv: Servo vs. Cam vs. Pneumatic
servo-tsav eccentric cams yog siv nyob rau hauv kev tsim ntawm niaj hnub backcover hnab ua tshuab es tsis txhob ntawm pneumatic thooj voos kheej kheej. Lub tshuab servo muab kev tswj xyuas qhov tseeb, kev nrawm nrawm thiab nrawm, thiab tiag tiag - lub sijhawm tswj hwm. Pneumatic systems raug nqi tsawg, tab sis kev siv cov cua compressed nce nqi khiav hauj lwm. Lawv kuj tuaj yeem poob siab sealing ntawm kev kub ceev vim qeeb hauv huab cua compression. servo- tsav hauv qab sealers tuaj yeem txo cov tswv cuab tag nrho los ntawm 23% tshaj tsib xyoos piv rau cov qauv pneumatic, raws li 2024 Ntim Machinery Industry Research Report.
D. Kev pub zaj duab xis thiab sau npe
Tsav- hla cov menyuam nrog cov tshuab clamping, tsis yog cov kab seev cev tsis zoo, pab ua kom cov yeeb yaj kiab nruj ruaj khov los ntawm qhov chaw nres tsheb rau qhov chaw sib khi. Lub hnab luam ntawv sau npe raug yog qhov tseem ceeb thiab yuav tsum tsis pub dhau ± 0.5 hli. Cov neeg muab khoom ntawm optical sensors nrog kaw -loop servo kho tau qhia kev txhim kho tshuab tswj thiab engineering peev xwm.
Kauj Ruam 3: Ntsuam xyuas Kev Tswj Ecosystem thiab Cov Ntaub Ntawv Traceability
Tus tsim lub hnab ev ntawv txhim khu kev qha yuav tsum txuas nrog koj qhov kev tsim ua tiav (MES) lossis muab cov ntaub ntawv ntxaws ntxaws. Nov yog qee yam yuav tsum tau saib xyuas thaum kuaj nrog cov neeg muag khoom:
- PLC hom thiab qauv-Hom tsis yog qhov tseem ceeb tshaj plaws, tab sis PLC yuav tsum yog cov khoom lag luam uas muaj kev txhawb nqa zoo thiab kev pabcuam.
- HMI touchscreen ua haujlwm-Tus kheej- kuaj npo. Koj tuaj yeem kho qhov kub thiab txias, sealing lub sij hawm thiab siab nyob rau hauv peb kauj ruam? Cov lus ceeb toom puas yooj yim to taub ua lus Askiv lossis lus hauv zos, tsis yog siv cov lej yuam kev tsis meej?
- Cov ntaub ntawv kaw cia thiab tso tawm- lub tshuab puas tuaj yeem tuav qhov ntsuas kub, lub puab tsaig siab thiab lub hnab ntim nrog lub sijhawm ntawm lawv? Cov ntaub ntawv no muaj txiaj ntsig zoo rau ISO 9001 kev tswj hwm zoo thiab FDA traceability checks.
- Kev sib txuas ntawm cov chaw taws teeb - Cov neeg muag khoom muab VPN-raws li kev txhawb nqa rau cov chaw taws teeb thiab cov neeg siv khoom- tswj kev nkag tau ua rau pom kev ntseeg siab hauv lawv cov txheej txheem thiab tom qab- kev muag khoom.
ISA-95 (Kev koom ua ke ntawm kev lag luam thiab kev tswj hwm lub tshuab) muab cov lus qhia tseem ceeb hauv cheeb tsam no. Koj lub tshuab yuav tsum muaj peev xwm txhawb nqa qib 2 thiab 3 cov ntaub ntawv sib txuas lus yam tsis tas yuav tsum tau hloov kho dua tshiab rau yav tom ntej.
Kauj Ruam 4: Xav tau pob tshab Spare Parts thiab Consumables Policy
Qhov no yog ib qho teeb meem rau ntau tus neeg yuav khoom hauv tsev. Hauv qab sealing tshuab manufacturers tuaj yeem muab cov nqi tshuab qis dua tab sis them tus nqi siab dua tom qab hloov qhov tshwj xeeb. Nug cov neeg muag khoom tshwj xeeb txog:
Cov khoom siv twg yog tus qauv (xws li cov kabmob sib xyaw, cov ntsuas ntsuas thiab cov hlua khi) thiab qhov twg yog kev cai- ua (xws li tshwj xeeb sealing puab tsaig, cam followers thiab cov lus qhia)?
Thov peb - xyoo daim ntawv teev cov khoom seem uas qhia txog qhov kwv yees zaus ntawm kev hloov. Sealant daim kab xev, piv txwv li, yuav tsum tau hloov txhua 500,000 lub voj voog thiab lub tshuab rhaub dej kub txhua 2,000 teev ua haujlwm.
Lub sijhawm xa khoom rau qhov tseem ceeb xws li servo motors, seals thiab tswj vaj huam sib luag yog dab tsi? Nws yog ib qho kev coj ua hauv kev lag luam rau cov khoom xa tuaj hauv 48 teev thiab 5 hnub ua haujlwm ntawm tus neeg muag khoom qhov chaw. Raws li ISO 13374 tus qauv saib xyuas tus mob, cov tshuab tuaj yeem tsim kho tsis zoo yog tias hloov lub puab tsaig yooj yim ua rau poob qis dua 4 teev.
Cov kev cai txhawb nqa khoom kuj tuaj yeem sab laj. Cov tuam txhab lag luam ntseeg siab yuav tsum txuas ntxiv txhawb nqa cov qauv hauv qab lub hnab ntim khoom rau tsawg kawg 10 xyoo tom qab muag lub tshuab kawg. Lawv yuav tsum muab yam tsawg kawg 12 lub hlis 'kev ceeb toom ua ntej tso tseg kev txhawb nqa rau cov khoom tseem ceeb.
Kauj ruam 5: Hais kom siv zaj duab xis rau lub Hoobkas txais
Tsis txhob xaiv lub tshuab raws li kev ua yeeb yaj kiab ua yeeb yam nkaus xwb. Ib tus neeg muab kev ntseeg siab yuav tsum tso cai rau koj lossis tus kws tshaj lij thib peb uas ntseeg siab tau siv koj tus kheej zaj duab xis rau kev lees paub ntawm lub Hoobkas, tsis yog lawv cov ntaub ntawv xeem. Thaum lub sij hawm FAT, lub hauv qab sealing lub hnab ua tshuab yuav tsum tau sib tw nrog koj cov qib zaj duab xis tiag tiag los xyuas kom meej kev foob nyob rau hauv cov khoom tiag tiag. FAT, xyuas cov hauv qab no:
Foob lub zog -50 lub hnab sib law liag tau sau thiab sim rau tev thiab tawg. ASTM F88 yuav tsum muaj qhov tsawg kawg nkaus tev quab yuam ntawm 2.5 N / 15 hli hauv ntau daim ntawv thov ntim khoom noj, tab sis koj cov khoom yuav xav tau ntau dua.
Lub ntsej muag foob-Kuaj xyuas qhov wrinkles, hlawv cov cim lossis qhov chaw kaw tsis zoo. dye penetration testing (ASTM F1929) tau siv los tshawb nrhiav cov xaim me me.
Kev ruaj ntseg ceev-Txhua theem Khiav lub tshuab ntawm 80%, 100% thiab 110% ntawm nws lub hom phiaj ceev rau 30 feeb. Tshawb xyuas qhov kev hloov pauv ntawm qhov sib khi. Qhov kub sib txawv yuav tsum nyob hauv + -3℃.
Kev hloov pauv raws sijhawm-yuav kom tus neeg teb xov tooj kho qhov loj ntawm lub hnab los ntawm ib mus rau lwm qhov. Kev tsim kho tshuab yuav tsis ua haujlwm zoo yog tias kev hloov kho tshuab siv sijhawm ntau dua 20 feeb yam tsis tau hloov lub cuab yeej.
Tus neeg muag khoom tus txheej txheem FAT yuav tsum ua raws li ISO 10472-2 kev nyab xeeb thiab kev ntsuas kev ua haujlwm rau cov tshuab ntim khoom. Yog tias tus neeg muag khoom tsis muaj daim ntawv teev FAT meej, nws yuav tsum raug suav hais tias yog daim ntawv ceeb toom.
Kauj Ruam 6: Kev tshuaj xyuas ntawm cov khoom txhawb nqa tom qab
Hauv qab- cov tshuab sealing yog lub sijhawm ntev - kev nqis peev thiab feem ntau yog 10 - 15 xyoo. Tom qab- kev pab cuam muag khoom yog qhov sib txawv ntawm tus neeg muag khoom siv yooj yim thiab tus neeg koom tes ntev ntev -. Thaum ntsuam xyuas cov neeg muab khoom, xyuas cov hauv qab no:
Pab neeg ua haujlwm pabcuam - Muaj pes tsawg tus kws ua haujlwm pabcuam ua haujlwm hauv koj cheeb tsam? Lawv lub sijhawm teb nruab nrab yog dab tsi, suav nrog kev kuaj mob thiab kho lub sijhawm, tsis yog lub sijhawm taug kev xwb?
Kev cob qhia -Koj puas muaj nyob rau ntawm - qhov kev cob qhia kev teeb tsa (tsawg kawg 3 hnub) thiab kev cob qhia taug qab online? Thov ib tug qauv kev npaj npaj. Nws yuav tsum suav nrog kev hloov lub puab tsaig, qhov ntsuas qhov ntsuas kub ntawm qhov ntsuas, thiab cov txheej txheem ua haujlwm thaum muaj xwm txheej ceev.
Lub Sijhawm Warranty-Kev lag luam dav dav warranty ntawm 12 lub hlis lossis 2,000 teev, qhov twg los ua ntej. Qee cov neeg muag khoom muaj kev lav 24 lub hlis ntawm servo motors thiab tswj cov tshuab, qhia tias lawv muaj kev ntseeg siab dua hauv lawv cov khoom siv.
Cov neeg siv kev txhawb nqa thiab kev pab cuam - Puas yog cov tuam txhab muab cov yeeb yaj kiab saib xyuas, cov lus qhia daws teeb meem, thiab cov npe khoom seem hauv online? Cov ntaub ntawv zoo digital txo qhov xav tau kev txhawb nqa xov tooj ntau zaus.
ntim cov khoom lag luam poob qis hauv kev ua zaub mov yog $ 1,200 txog $ 2,800 toj ib teev, raws li phau ntawv Journal of Manufacturing Technology Management (No. 33, 2022). Kev txhawb nqa sai thiab ua haujlwm tau zoo tuaj yeem txo qis kev tsim khoom.
Kauj Ruam 7: Tshawb xyuas Kev Ua Raws Cai thiab Ntawv Pov Thawj Daim Ntawv Pov Thawj
Kev ntseeg tau ntawm kev ua haujlwm pib nrog cov qauv tsim nyog. Txhua tus tsim lub hnab ev ntawv yuav tsum ua raws li cov cai hauv qab no:
Kev nyab xeeb hluav taws xob-Lub tshuab yuav tsum yog CE, UL lossis CCC tau ntawv pov thawj, raws li lub hom phiaj ua lag luam.
Kev Tiv Thaiv Kev Nyab Xeeb Lub Tshuab-EN 415-5 (Txoj Cai Kev Nyab Xeeb Lub Hnab Ntim Tshuab) txhais cov kev cai rau kev tiv thaiv kev nyab xeeb, kev sib cuam tshuam, kev tswj tes, thiab kev ua haujlwm thaum muaj xwm txheej ceev.
Kev tsim qauv huv huv-Rau daim ntawv thov ntim khoom noj, xyuas tias cov tshuab siv cov khoom noj- qib roj nplua nyeem (NSF H1) thiab cov khoom siv tiv thaiv corrosion yog siv rau hauv qhov chaw kaw. 316 stainless hlau yog nyiam.
Cov neeg thib peb yuav tsum tau muab cov ntawv xeem, tsis yog tsuas yog daim ntawv pov thawj uas muab los ntawm cov neeg xa khoom. Cov tuam txhab lag luam ntseeg siab yuav tsum muab ETL lossis TÜV cov ntawv ceeb toom thaum thov. Kuj xyuas tias tus neeg muag khoom qhov kev tswj hwm zoo yog ISO 9001: 2015 daim ntawv pov thawj. Txawm hais tias qhov no tsis yog ib txwm tsim nyog, nws qhia tau tias cov tuam txhab ua raws li cov txheej txheem tsim khoom thiab cov txheej txheem tswj kom zoo.
Kauj Ruam 8: Sib piv Tus Nqi Tag Nrho Cov Tswv Cuab (TCO), tsis yog tus nqi yuav khoom xwb
Cov hnab ev khoom pheej yig tshaj plaws yuav yog qhov kim tshaj plaws tshaj 5 xyoos. Siv cov tswv yim no, TCO qauv tau tsim:
Tus Nqi Cov Ntsiab Lus Sib Piv
Tus nqi pib ntawm peev 100% lub hauv paus
Installation thiab commissioning 5-8% ntawm peev
Kev saib xyuas txhua xyoo (cov khoom seem + kev ua haujlwm) 4-6% ntawm peev
Kev siv hluav taws xob (hluav taws xob + cua) 2-4% peev / xyoo
Tus nqi poob qis (cov khoom poob) Muaj qhov sib txawv heev
Rov muag tus nqi tom qab 5 xyoos 30-50% ntawm peev
Txhua tus neeg muag khoom yuav tsum tau muab cov ntaub ntawv teev tseg nruab nrab ntawm lub sijhawm ua haujlwm los ntawm cov neeg siv khoom uas twb muaj lawm. Cov tshuab uas tsim tau 120 hnab ib feeb twg muaj 2% nce nyob rau hauv uptime (los ntawm 96% mus rau 98%) thiab tuaj yeem ntxiv 1,150 hnab rau ib qho kev ua haujlwm. Qhov kev tsim khoom ntxiv tuaj yeem txaus them 15-20% ntxiv rau lub hnab ntim khoom lag luam txhim khu kev qha.
Kauj Ruam 9: Nug cov neeg siv khoom kom pom zoo thiab mus saib lawv cov kev teeb tsa
Cov neeg muag khoom yuav tsum muab tsawg kawg peb daim ntawv pov thawj cov neeg siv khoom los ntawm koj qhov kev lag luam, tsis yog cov chaw tsim khoom nruab nrab lub hnab. Hu rau cov neeg siv khoom no nrog cov lus nug tshwj xeeb:
"Lub tshuab puas tau ncav cuag qhov xav tau ntau lawm hauv thawj lub hlis?"
"Ntau npaum li cas koj tau hloov lub foob los yog lub rhaub dej kub piv rau lub neej kev pab cuam tau cog lus los ntawm tus neeg muag khoom?"
"Nws siv sijhawm ntev npaum li cas kom tau txais kev txhawb nqa hauv xov tooj thiab nws siv sijhawm pes tsawg hnub rau cov kws tshaj lij tuaj txog thaum lub tshuab tawg?"
"Koj puas yuav ib lub hnab ev ntawv dua?"
Yog tias ua tau, mus ntsib tus neeg siv khoom lub Hoobkas yam tsis muaj ntawv ceeb toom ua ntej lossis thov kev hu xov tooj nyob hauv video thaum lub tshuab ua haujlwm. Saib xyuas cov suab nrov, cov plua plav plua plav thiab kev ua haujlwm ntawm lub tshuab thaum lub sijhawm ua haujlwm. Cov ntsiab lus no feem ntau tsis pom hauv cov yeeb yaj kiab ua qauv qhia txog kev tu cov nroj tsuag.
Daim ntawv txheeb xyuas zaum kawg ua ntej kos npe rau daim ntawv yuav khoom
Ua ntej txiav txim siab zaum kawg, thov ua kom tiav daim ntawv txheeb xyuas qhov tseeb no:
Cov ntawv qhia tshwj xeeb yog tag nrho raws li hom zaj duab xis thiab qhov loj ntawm lub hnab.
FAT hnub tau lees paub los ntawm koj tus kheej zaj duab xis.: Cov npe khoom seem suav nrog sau nqi thiab lub sijhawm xa khoom.
Cov phiaj xwm kev cob qhia muaj xws li lub sijhawm qhia thiab cov neeg ua haujlwm ua haujlwm muaj.
Cov ntsiab lus Warranty qhia meej meej txog qhov kev lav phib xaub, suav nrog tus nqi ntawm kev mus ncig thiab chaw nyob rau Warranty service visits.
Cov sij hawm them nqi yog hais txog kev xa khoom, kev pom zoo FAT thiab kev ua tiav tshuab ua tiav, tsis yog kev xa khoom xwb.
Xaus:
Xaiv ib lub hnab ntim khoom lag luam txhim khu kev qha tsis yog ib qho teeb meem ntawm kev sib piv cov khoom specifications. Nws yuav tsum tau ua tib zoo tshuaj xyuas cov txheej txheem tshuab, tswj cov tshuab, kev pab txhawb nqa, tag nrho cov nqi, thiab cov lus pom zoo rau cov neeg siv khoom. Los ntawm kev siv cuaj-txoj kev ntsuas cov kauj ruam no, cov neeg yuav khoom tuaj yeem txiav txim siab zoo dua raws li kev ua haujlwm ntawm lub cuab yeej, tsis yog tsom rau tus nqi xwb. Ib lub tuam txhab txhim khu kev qha yuav tsum txaus siab los teb cov lus nug ntxaws thiab muab cov ntaub ntawv meej meej txog lawv cov tshuab. Ib qho dej zoo- xaiv lub hnab ntim hauv qab ua tshuab muab lub zog sib khi zoo ib yam, txo cov khoom pov tseg, thiab muab cov nyiaj rov qab zoo rau kev nqis peev tshaj nws lub neej ua haujlwm.
Tus nqi tiag tiag ntawm kev xaiv zoo tsis yog tus nqi yuav khoom xwb. Nws tuaj yeem suav nrog cov neeg siv khoom tsis txaus siab txog lub hnab ntim khoom, kev kho tsis raug cai, thiab txo cov sijhawm ua lag luam. Ua tib zoo ua ntej- kev soj ntsuam kev yuav khoom yuav pab xyuas kom meej tias koj lub hnab ntim khoom hauv qab muab qhov ruaj khov ruaj khov zoo, txo cov khoom pov tseg, thiab muaj kev ua haujlwm ntev.
Cov ntaub ntawv pov thawj: ASTM F88 (Seal Strength Test), ASTM F1929 (Dye Penetration Test), ISO 527-3 (Plastics Tensile Properties), VDI 3830 (Machine Dynamics), ISA-95 (Enterprise-Control Integration), ISO 13tusufring Technology (Management Voltage) 10472-2 (Packaging Mechanical Safety), PMMI 2024 Txhua tus qauv thiab cov ntawv tshaj tawm tuaj yeem siv tau los ntawm lawv lub koom haum tshaj tawm.
