Yeeb nkab ovality thiab rov puag ncig: Yuav ua li cas qhov gap cuam tshuam rau weld

Ib qho fusion fitting yog ib qho chaw txuas kom raug. Nws qhov qhib yog tsim rau ib lub raj uas muaj qhov dav sab nraud tshwj xeeb, thiab cov khoom melted uas tsim lub joint yuav tsum puv ib qho chaw me me tsim. Yog tias lub raj deform me ntsis, qhov chaw ntawd tsis yog lawm: tight ib sab, loosening sab lwm sab. Koj tseem tuaj yeem muab fitting rau, lub system tseem ua tiav nws lub voj voog, tab sis qhov txuas tseem puas.

Ovality ua dab tsi hauv qhov fitting

Thaum sib xyaw, melt pool xav tau qee qhov siab kom sib sau ua ke. Qhov siab no los ntawm cov khoom nthuav tawm los ntawm kub, raug kaw nruab nrab ntawm phab ntsa yeeb nkab thiab qhov txuas. Thaum yeeb nkab kov qhov txuas, siab nce thiab cov nto sib txuas ua ke. Tab sis yog muaj qhov chaw, melt tsuas puv qhov chaw ntawd es tsis txhob nias cov nto ua ke, yog li tsis muaj siab tsim ntawm qhov sib txuas thiab tsis muaj kev sib txuas. Qhov tshwm sim yog ib qho txuas uas txuas ib feem ntawm lub voj voog thiab qhib ib ncig ntawm qhov seem-ib txoj kev ntws dej uas tej zaum tsuas tshwm sim thaum kab muaj zog.

Where ovality comes from

Source	What happens
Coiled pipe	Lub coil tseem nyob txawm tias koj qhib nws tawm, thiab lub raj zoo li oval raws nws txoj kev ntev.
Storage	Cov yeeb nkab stacked lossis cov yeeb nkab hauv qab pallets raug nias hauv ob peb lub lis piam, tshwj xeeb thaum huab cua sov
Trench conditions	Ib lub raj uas muab tso rau hauv av tsis sib npaug yuav nqes raws nws tus kheej lub cev hnyav thiab av ib puag ncig.
Handling	Kev tuav tsis zoo, poob, lossis clamp nrog qhov ncauj tsis zoo
Heat	Lub hnub ci ncaj qha rau ntawm cov raj stacked ua rau lawv mos, thiab qhov flat nyob thaum lawv txias.
Cutting	Txiav nrog rab riam uas nias lub raj ua ntej txiav yuav ua rau qhov kawg tawg

Ib lub raj coiled me me yog ib qho piv txwv classic. Nws muaj ib qho puab pom tseeb, cov neeg ua haujlwm kho nws ncaj los ntawm tes, thiab qhov kawg uas nkag mus rau hauv qhov txuas tseem yog oval hauv daim duab.

How to check

Kev tshuaj xyuas no ceev txaus kom tsis muaj laj thawj hla nws. Ua ob zaug ntsuas ntawm lub kaum sab xis ntawm qhov kawg ntawm lub raj, qhov chaw uas lub fitting yuav mus. Qhov txawv ntawm qhov loj tshaj thiab qhov me tshaj plaws yog qhov ovality; qhia nws raws li feem pua ntawm qhov dav nominal. Cov neeg tsim fitting qhia qhov siab tshaj plaws uas lawv cov khoom tuaj yeem nqa tau-feem ntau yog ib feem pua tsawg heev-thiab txhua yam dhau qhov ntawd yuav tsum tau kho dua ua ntej sib dhos. Khiav ib qho kab ncaj ntawm qhov kawg ntawm lub raj kuj qhia tau cov chaw flat uas caliper ntawm ib qho axis yuav tsis pom.

Re-rounding in practice

1. Rov puag lub raj ua ntej qhov kawg. Rov puag dua ua rau saum npoo uas koj tsuas ua tsis raug.
2. Siv lub clamp rov puag ncig kom raug rau lub raj, tsis yog lub wrench saw lossis ib lub hlua ua si. Qhov siab ntawm qhov chaw tuaj yeem tsim cov chaw tiaj tiaj es tsis txhob coj nws rov qab mus rau ib lub voj voog.
3. Khaws clamp rau thaum fusion thiab tag nrho lub sijhawm txias. Hauv ntau txoj haujlwm, re-rounding clamp kuj ua haujlwm raws li kev txwv uas thaiv kev txav.
4. Xyuas dua qhov tob ntawm lub raj tom qab clamping: rov puag dua tuaj yeem txav ib lub raj luv tawm deb ntawm qhov txuas.
5. Rau rooj zaum, hloov kho qhov tseem ceeb hauv qab rooj zaum thiab khaws lub clamp hauv qab kom txog thaum nws txias.

Gap, kav dej me me, thiab khawb dhau

Ovality tsuas yog ib qho laj thawj uas ua rau qhov chaw qhib tshwm sim. Ib lub raj uas muaj qhov dav sab nraud qis dua qhov tso cai, lossis ib qho uas tau raug ntxuav ntau dhau, yuav ua rau muaj teeb meem tib yam thoob plaws. Txhuam tob dhau yog ib qho kev pheej hmoo tiag thaum sim tshem tawm qhov txhab tob: cov khoom poob sai, thiab poob tsuas yog 1 mm phab ntsa ntawm ib qho txuas phab ntsa nyias yuav yog qhov txawv ntawm kev sib txuas zoo thiab qhov ntws. Yog muaj kev tsis ntseeg, ntsuas lub raj tom qab ntxuav, thiab yog tias ib qho txuas yooj yim dhau, nres thiab xyuas qhov dav es tsis txhob cia siab tias nws yog ib txwm.

Cov lus nug nquag nug

Kuv puas tsuas yog muab ib lub raj oval tso rau hauv qhov txuas xwb?

Koj ua tau, thiab nws yuav haum. Qhov koj ua tsis tau yog ua kom muaj qhov sib npaug thoob plaws. Ua kom puag dua ua ntej.

Puas yog ovality tseem ceeb rau cov kab uas hla me?

Qhov tseem ceeb tshaj plaws yog qhov ntawd. Lub raj coiled me me nqa coil set muaj zog tshaj plaws, thiab lub fitting muaj phab ntsa nyias tshaj plaws los tswj txhua qhov chaw tsis sib npaug.

Kuv puas tuaj yeem rov ua dua tom qab scraping?

Tsis yog. Clamping deform thiab tso cim rau saum nto npaj. Rov puag nws, tom qab ntawd rub nws, ces sib sau ua ke.

Lub clamp rov puag ncig yuav tsum nyob ntev npaum li cas?

Txog thaum qhov fitting txias lawm. Nws yog ib feem ntawm kev khi, tsis yog tsuas yog ib qho cuab yeej npaj xwb.