Thermal hnav thiab cobalt tshem tawm ntawm PDC

I. Thermal hnav thiab cobalt tshem tawm ntawm PDC

Nyob rau hauv cov txheej txheem siab Sintering cov txheej txheem ntawm PDC, cobalt ua raws li cov hniav sib xyaw ua ke nrog cov roj av geological thiab cov coj nruj heev,

Diamonds tshav kub kuj yog tsawg heev. Nyob rau hauv atmospherer siab, nto ntawm pob zeb diamond tuaj yeem hloov pauv ntawm qhov kub nyob ib puag ncig 900 ℃ lossis siab dua. Thaum siv, tsoos PDCs ib txwm yuav ua rau muaj tseeb ntawm 750 ℃. Thaum drilling los ntawm kev nyuaj thiab cov pob zeb abrasive tuaj yeem txuas tau yooj yim dua, thiab ntau dua li cov lus me me ntawm cobalt (1495 ° C).

Piv rau cov pob zeb diamond ntshiab, vim muaj cov cobalt, pob zeb diamond hloov mus rau graphite ntawm qhov kub qis dua. Raws li qhov tshwm sim, hnav lub pob zeb diamond tshwm sim los ntawm kev ua pa tawm los ntawm cov cua sov hauv nruab nrab. Additionally, the thermal expansion coefficient of cobalt is much higher than that of diamond, so during heating, the bonding between diamond grains can be disrupted by the expansion of cobalt.

Xyoo 1983, ob tug kws tshawb nrhiav ua tau lub pob zeb diamond tshem tawm ntawm cov txheej txheem PDC pob zeb diamond txheej, ua kom zoo tshaj plaws ntawm pdc hniav. Txawm li cas los xij, qhov kev tsim tawm no tsis tau txais cov xim nws tsim nyog. Nws tsis yog txog tom qab 2000 uas, nrog kev nkag siab tob ntawm PDC pob zeb diamond txheej, cov laum chaw muag khoom pib thov siv cov hniav pdc rau hauv pob zeb drilling. Cov hniav kho nrog cov qauv no yog tsim nyog rau cov kev sib txawv uas muaj kev sib thooj nrog cov ntaub ntoo loj thiab yog hu ua "de-cobalted" cov hniav.

Qhov thiaj li hu ua "de-cobalt" yog tsim nyob rau hauv cov kev ib txwm txheej yog immersed nyob rau hauv cov zog acid kom tshem tawm theem cobalt los ntawm cov acid etching txheej txheem. Qhov tob ntawm kev tshem tawm ntawm kev tshem tawm tuaj yeem ncav cuag txog 200 microns.

Kev ntsuas kev coj ua hnyav tau ua rau ob tus hniav PDC zoo ib yam (ib qho ntawm cov uas tau tshem tawm cov txheej diamond txheej). Tom qab txiav 5000m ntawm Granite, nws tau pom tias cov hnav tus nqi ntawm cov tsis yog cobalt-tshem PDCT-tshem PDC pib nce ntau yam. Nyob rau hauv kev sib piv, tshem tawm PDC khaws tseg ib qho tseem ceeb ntawm cov khoom nrawm thaum txiav kwv yees li 15000m ntawm pob zeb.

2. Nrhiav txoj kev ntawm PDC

Muaj ob txoj hauv kev los tshawb xyuas PDC cov hniav, yog kev sim ua kom muaj kev sim siab thiab tsis yog kev ua phem.

1. Puas Tsuaj Kev Kuaj

Cov kev ntsuam xyuas no tau npaj rau simuling downhole kev mob raws li qhov muaj peev xwm los ntsuas kev ua tau zoo ntawm cov kab mob zoo li no. Ob daim ntawv tseem ceeb ntawm kev sim ua puas tsuaj yog kev ntsuas tiv thaiv thiab cuam tshuam kev ntsuam xyuas.

(1) Kev coj tawm tsam

Peb hom khoom siv tau siv los ua PDC hnav kev ntsuam xyuas:

A. Ntsug Tshuab Dhos (VTL)

Thaum lub sijhawm kuaj, ua ntej kho PDC BDC me me mus rau VTL tshuab dhos thiab muab pob zeb pob zeb (feem ntau granite) nyob ib sab ntawm PDC. Tom qab ntawd tig lub pob zeb qauv nyob ib ncig ntawm cov tshuab dhos axis ntawm qee qhov ceev. PDC me ntsis txiav mus rau hauv lub pob zeb qauv nrog ib qho tob. Thaum siv cov pob zeb rau kev sim, qhov tob no feem ntau tsawg dua 1 hli. Qhov kev ntsuas no tuaj yeem yog qhuav lossis ntub dej. Hauv "qhuav VTL kuaj," Thaum PdC me ntsis txiav los ntawm pob zeb, tsis muaj txias txias; Txhua qhov kev sib txhuam kub ua rau nkag rau hauv PDC, nrawm ntawm cov txheej txheem graphitization ntawm lub pob zeb diamond. Txoj kev ntsuas sim no tau ua rau cov txiaj ntsig zoo tshaj plaws thaum ntsuas PDC rau cov xwm txheej zoo siab lossis nrawm nrawm.

Lub "ntub vtl kuaj" txheeb xyuas lub neej pdc nyob rau hauv me me cua sov los ntawm txias pdc hniav nrog dej los yog huab cua thaum sim. Yog li ntawd, qhov tseem ceeb hnav qhov chaw ntawm qhov kev sim no yog kev sib tsoo ntawm cov pob zeb coj mus rau cov cua sov.

B, kab rov tav

Qhov kev ntsuas no tseem tau nqa tawm nrog granite, thiab lub hauv paus ntsiab lus ntawm kev ntsuas yog ib qho zoo ib yam li VTL. Lub sijhawm xeem tsuas yog ob peb feeb, thiab lub thermal poob siab ntawm granite thiab pdc cov hniav yog tsawg heev.

Cov khoom siv granite siv los ntawm PDC iav cov chaw muag khoom yuav sib txawv. Piv txwv li, cov kev ntsuas ntsuas uas siv los ntawm cov tuam txhab hluavtaws thiab cov khoom siv hluav taws xob zoo ib yam nkaus, tab sis lawv siv tib lub pob zeb zoo tib yam thiab muaj zog ntawm lub zog ntawm 190MPA.

C. Kev ntsuas piv ntsuas qhov ntsuas

Nyob rau hauv cov xwm txheej tshwj xeeb, lub pob zeb diamond txheej ntawm PDC yog siv los txiav silicon carbide sib tsoo log, thiab cov nqi ntawm cov looj ntsuas ntawm PDC, uas yog hu ua kev sib piv.

(2) kev ntsuas cuam tshuam tiv thaiv

Cov qauv rau kev soj ntsuam cuam tshuam cuam tshuam nrog kev txhim kho PDC cov hniav ntawm lub kaum ntawm 15-25 degrees thiab tom qab ntawd poob lub pob zeb diamond txheej ntawm tus hniav pob zeb diamond ntawm cov hniav pdc. Qhov hnyav thiab qhov siab ntawm txoj kev poob khoom uas cuam tshuam txog qhov kev sim siab tus hniav, uas tuaj yeem maj mam nce mus txog 100 Joules. Txhua tus hniav yuav raug cuam tshuam 3-7 zaug kom txog thaum nws tsis tuaj yeem sim txuas ntxiv. Feem ntau, tsawg kawg 10 qhov piv txwv ntawm txhua hom hniav yog kuaj ntawm txhua qib hluav taws xob. Txij li muaj ib qho ntau hauv cov hniav tiv thaiv hniav kom cuam tshuam, qhov kev xeem ua tau ntawm txhua qhov chaw hluav taws xob yog qhov nruab nrab ntawm pob zeb diamond mus tom qab cuam tshuam rau txhua tus hniav.

2. Cov tsis yog-kev sim ua txhaum

Cov txheej txheem ntsuas dav siv tsis yog - uas tsis yog qhov muag pom thiab tshuaj ntsuam me me) yog ultrasonic scanning (CSCAN).

C scanning tshuab tuaj yeem kuaj cov tsis xws luag me me thiab txiav txim siab qhov chaw thiab qhov loj me ntawm qhov tsis xws luag. Thaum ua qhov kev ntsuas no, thawj qhov chaw pdc hniav nyob hauv dej tank, thiab tom qab ntawd luam theej duab nrog kev sojntsuam ultrasonic;

Kab lus no tau luam tawm los ntawm "Thoob Ntiaj Teb Hlau Hlau"