New diamond composite ultrahard material for drilling of hard rocks (Sobolev)
-
Upload
sergey-sobolev -
Category
Engineering
-
view
283 -
download
4
Transcript of New diamond composite ultrahard material for drilling of hard rocks (Sobolev)
New$diamond$composite$ultrahard$material$for$drilling$of$hard$rocks$
Sergei&Sobolev&Russian&State&University&of&Oil&and&Gas&
Supervisor:&E.E.&Ashkinazi&Prokhorov&InsAtute&of&General&Physics&&&
Shortly$about$the$department$
There%are%7%research%laboratories%in%the%department:%•&Laboratory&of&metallographics&•&Laboratory&of&corrosion&•&Laboratory&of&tribology&•&Laboratory&ofµFarc&oxidaAon&•&Laboratory&of&soldering&and&restoraAon&of&diamond&tools&•&Laboratory&of&ion&vacuum&coaAngs&
2&
www.gubkin.ru&&
Application$
Currently,&diamond&tools&are&mainly&used&for&drilling&hardest&rocks.&Materials&with&improved&wear&resistance&need&to&be&used&for&drilling&on&oilfields&(for&example&sea&shelf,&oil&and&gas&fields&in&Eastern&Siberia,&etc.).& 3&
Core$drill$bits$with$diamond$inserts$
4&
One&type&of&rock&destrucAon&tool&is&a&diamond&core&drill&bits.&The&main&element&of&a&core&drill&bit&is&a&diamond&cuSer.&
diamond&cuSer/inserts&
Disadvantages+of+currently+used+core+drill+bits++
5%
• Insufficient&removal&of&the&sludge&(debris)&from&the&acAve&zone&• Uneven&wear&of§ors&of&core&drill&bits&• Fast&wear&of&diamond&inserts&• Insufficient&cooling&• Insufficient&fixing&of&insert&with&a&matrix&&• Not&opAmized&size&of&diamond&grains&in&the&matrix&• Not&opAmized&locaAon&of&diamond&inserts&in&the&cuSer&
We&have&analyzed&the&patents&from&different&countries&over&the&last&fiZy&years.&Currently,&there&are&disadvantages&of&diamond&core&drill&bits&as&following:&
Analysis+of+patents.+Results+
6&
As%a%result:%F&Low&drilling&speed&F&High&wear&of&the&core&drill&bits&F&Low&energy&efficiency&
NB!%Presently,%the&wear&mechanisms&during&drilling&of&hardest&rocks&by&a&core&drill&bit&are&the&polishing/grinding&(because&hardness&of&
cuSers&is&only&approximately&50&GPa).&
Examples&of&the&polishing/grinding/cu_ng&wear&mechanisms&will&be&shown&in&the&next&slides.&
It%is%very%important%to%stress%difference%in%abrasive%mechanisms%%(polishing/grinding/cu_ng).&
Difference$in$abrasive$mechanisms$$
7&
Polishing/Grinding%%homogeneous&sludge&(debris)&&
size%of%50*80%micron%
Grinding/CuCng%nonhomogeneous&sludge&(debris)&&sizes%of%50*80%and%100*200%micron%
Analysis+of+patents.+Decisions+
8&
The%properDes%of%the%diamond%core%drill%bit%must%be%improved:%• To&provide&the&combinaAon&of&two&processes,&the&grinding&and&cuCng.&This&is&possible&if&there&is&an&element&of&hardness&of&100&GPa&or&more.&
• To&use&materials&with&different&hardness&in&the&structure&of&matrixFcompositeFdiamond&(25/50/100+&GPa).%
&But%hardness%of%100%GPa%is%the%hardness%of%the%natural%diamond,%which%means:%(а)&high&cost&(b)¬&opAmal&shape&of&cuSer&(octahedron)&&&
Hybrid+Ultrahard+Material$
Therefore&the&Bakul&InsAtute&for&Superhard&Materials&(NaAonal&Academy&of&Sciences&of&Ukraine)&and&Prokhorov&InsAtute&of&General&Physics&(Russian&Academy&of&Sciences)&developed&hybrid&ultrahard&polycrystalline&composite&material&(UHM)&with&a&polycrystalline&diamond&grown&by&CVD&method&(CVD&diamond).&
9&
The%problem%can%be%solved%by%using%CVDLdiamond%(hardness%140%GPa)%
Hybrid+Ultrahard+Material$
10&
• Hardness&of&CVDFdiamond&is&140&GPa&(40&GPa&higher&than&natural&diamond).&• The&shape&of&CVDFdiamond&insert&is&a&plate&(thickness&of&the&insert&does¬&
change&during&drilling).&
CVD&diamond&size:&4,0×1,0×0,5&mm&(length&x&width&x&thickness)&
DCTM%&
The&ultrahard&hybrid&material&(UHM)&includes&CVDFdiamond&insert&and&diamond&composite&thermostable&materials&(DCTM)&matriх&(around&CVDFdiamond&insert&)&The%UHM%has%the%following%properDes:%
Vickers$hardness$of$CVD>diamond$insert$
11&
The&hardness&value&was&found&by&the&following&formula&&HV#=#1.8544#*P/d2,&&
&
where&P%is&the&indentaAon&load,&d%is&the&arithmeAcal&mean&of&two&diagonals&of&the&indent.&&&The&indent&diagonals&were&measured&using&a&Neophot&opAcalµscope&at&
a&magnificaAon&of&х800.&
The&UHM&hardness&was&measured&on&a&PMTµtester&with&a&Vickers&diamond&pyramid&as&an&indenter&at&indentaAon&loads&of&4.9%and%9.8%N.%%
Patents+(Russia+and+Ukraine)$
12&
«Diamond%polycrystalline%composite%with%the%
reinforcing%diamond%component»%
Authors:%E.E.&Ashkinazi,&V.G.&Ral’chenko,&V.I.&Konov,&A.P.&Bolshakov,&S.&G.Ryzhkov,&S.S.&Sobolev&
Categories:%C04B35/528,&B24D3/04&
Date%of%applicaDon:%2013F07F19&Date%of%the%publicaDon:%2015F10F01&
This&UHM&material&is&protected&by&patents&in&Russia&and&Ukraine.&
The$hardness$gradient$
13&
Applying%of%an%ultrahard%component%(CVDLdiamond)%allows:%(a)&prefracture&of&rocks&by&cu_ng&as&a&wear&mechanism&(b)&progressive&rock&shredding&(c)&removing&drilling&sludge&(debris)&from&the&contact&area&(d)&increase&in&the&service&lifeAme&of&diamond&inserts&(d)&increasing&energy&efficiency&and&durability&core&drill&bit&
CVDLdiamond%(140%GPa)%%
DCTM%(~50%GPa)%
Diamond%matrix,%%body%of%the%drill%bit%(~25%GPa)%
Another&property&of&material&is&the&hardness&gradient.&
Structure$of$Ultrahard$Hybrid$Material$(UHM)$
UHM&is&a&diamond&polycrystalline&composite&with&CVDFdiamond&insert.&Composite&includes&the&dispersible&strengthening&addiAve&and&powders&of&diamond&and&metals.&&
14&
Structure,%Mas.%%%
Diamond&powder&and&CVD&diamond&insert&& 85F90&
Nickel&& 7F9&
Cobalt&& 2F4&
Nanopowder&of&tungsten&carbide&& 0,1F3,0&
The&UHM&was&sintered&in&a&high&︎pressure&process&in&two&stages:&&1. At&the&first&stage&the&material&was&subjected&to&heat&treatment&at&a&
pressure&of&8&GPa&and&temperature&of&1170&K&for&50&s.&&2. Then&the&temperature&was&increased&to&the&silicon&melAng&point&
temperature&(1570&K)&at&the&given&pressure&and&held&for&90&s.&
Chemical&Vapor&DeposiAon&(CVD)&of&diamond&
CVD&diamond&was&deposited&in&Methane&(CH4)/Hydrogen&(H2)&plasma&in&theµwave&oven&on&Si&substrate&on&the&UPSAF100&unit&• power&F&5&kW,&&• frequency&F&&2,45&GHz,&• gas&pressure&in&the&camera&F&95F100&Torr,&&• concentraAon&of&CH4&F&10%,&&• temperature&of&a&substrate&F&850F870&°C,&&• deposiAon&rate&~&5,0µns/h.&&&
AZer&deposiAon&the&diamond&plate&was&detached&from&Si&substrate&by&solving&of&substrate&in&acid&(HF).&Plate&was&cuSed&into&smaller&pieces&by&means&of&a&laserFbeam&technique.& 15&
Research$Hybrid&Ultrahard&Material&
16&
Turning$of$Korostyshev$granite$
The%main%task&was&to&study&wear&mechanisms&of&DCTM&with/without&CVDFdiamond&insert.&Two&samples&were&used:&
17&
&DCTM&without&CVD&diamond&& DCTM&with&CVD&diamond&&
DCTM%–%diamond%composite%thermostable%material%
The&wear&resistance&of&a&rock&destrucAon&tool&equipped&with&UHM&was&esAmated&in&a&turning&test&against&Korostyshev&granite&(drillability&index&–&XI,&high&hardness,&high&abrasive&resistance).&Test&was&done&on&the&DIPF200&screwFcu_ng&lathe.&
Properties$of$granite$Granite%is%used%as%a%hard%rock%material.%Its%properDes:%
• MediumFgrained&(the&size&of&grains&is&from&2&to&5&mm)&• Average&density&is&2600F2800&kg/m3&• Weak&porosity&(to&1,5%)&• Slight&water&absorpAon&(0,5%)&• Good&resistance&to&an&abrasion&• Compressing&strength&90&…&280+&MPa&
СomposiDon%of%granite:%• Feldspars&(about&40.&60%),&• Quartz&(20.&40%)&• IronFmagnesium&silicates&(to&10%)&• Micas&and&etc.&
18&
Wear$tracks$on$a$cylindrical$Korostyshev$granite$sample$$
19&
Wear$mechanism+
20&
DCTM%%
Polishing/Grinding%%homogeneous&sludge&(debris)&&
size%of%50*80%micron%
DCTM%with%CVD%%
Grinding/CuCng%nonhomogeneous&sludge&(debris)&&sizes%50*80%and%100*200%micron%
Wear&intensity&(mg/m)$Wear&intensity&on&DCTM+CVDFdiamond&insert&is&several&Ames&smaller&(5,5&Ames&for&black&CVD&and&10,4&Ames&for&white&CVD)&than&wear&intensity&on&DCTM&sample&without&CVDFdiamond&
21&
Wear&intensity,&10F3&mg/m&&
Wear%intensity%%=%∆m%/%L%∆m&&F&weight&loss,&mg&&L&F&path&length,&m&&
Effect$of$«Self>sharpening»$
22&
It&should&be¬ed&that&there&is&an&interesAng&effect&of&«selfFsharpening».&It&is&the&emergence&of&a&cone&with&sharp&edges&on&the&surface&of&DCTM&with&CVDFdiamond&insert.&This&effect&improves&the&abrasive&ability&of&the&cuSer.&
Tests$on$abrasive$wheels$
23&
Equipment%was%designed%for%the%study%of%tribological%properFes%of%
diamond%drilling%cuGer.%
Equipment$layout$
24&KinemaFc%scheme%
Sample$loading$setup$
25&
Abrasive%wheel%• Electrocorundum&• Ceramic&matrix&• Size&of&the&main&fracAon&of&600F700µns&• K6V2&brand&25&and&60&with&a&graininess&60&
Samples%• DCTM&• DCTM&with&CVDFdiamond&
Load&6F80&N&
Experimental$conditions$
26&
• Load&F&6F80&N&• Time&of&tests&–&12&s&F&30&min&• RotaAon&frequency&F&31F69&rpm.&
DCTM&and&DCTM+CVDFdiamond&samples&were&weighed&with&an&accuracy&of&±0,0001&g&(ViBRA&HD).&&
The&trajectory&of&the&sample&is&a&spiral&(«step»&F&5&and&10&mm).&&
Results$
27&
DCTM+CVD&DCTM&
Weight&loss,&mg&
Distance,&m
&
For&the&same&weight&loss&the&distance&in&the&case&of&DCTM&samples&was&about&10&Ames&smaller&than&in&the&case&of&DCTM+CVDFdiamond&samples.&&&
In&other&words,&the&lifeAme&of&DCTM+CVDFdiamond&samples&is&about&10&Ames&longer&than&for&DCTM&samples.&
Friction$tests$against$silicon&carbide$(SiC)$(Tribometer$T>10)$
The%main%task:%• Measurement&of&fricAon&
coefficient.&• Measurement&of&the&wear&
intensity&(mg/h)%on&silicon&carbide&against&DCTM&and&DCTM&with&CVDFdiamond&&samples.&
28&
The$results$of$friction$test$on$DCTM$sample$
• Load&Q=20F50N,&&• RotaAon&frequency&N=50&rpm&• Sliding&speed&Vck=0,1&m/s,&&• Diameter&of&the&sample&d=4&mm.&
• Total&Ame&of&the&experiment:&57,9&h&• Total&weight&loss:&∆m&=&5&mg&• Wear&intensity&(mg/h):&VDCTM=0,086&mg/h& 29&
FricDon%coefficient:%0,1F0,15&%%
The$results$of$friction$test$on$DCTM$with$CVD>diamond$insert$sample$
• Load&Q=20F50N,&&• RotaAon&frequency&N=50&rpm&• Sliding&speed&Vck=0,1&m/s,&&• Diameter&of&the&sample&d=4&mm.&
• Total&Ame&of&the&experiment:&2,0&h&• Total&weight&loss:&∆m&=&41&mg&• Wear&intensity&(mg/h):&VDCTM+CVD=20,5&mg/h&
30&
FricDon%coefficient:%0,11F0,48&%
Comparison$of$the$results$
• Wear&intensity&on&silicon&carbide&sample&(speed&of&weight&loss,&mg/h)&against&DCTM&with&CVDFdiamond&insert&in&dry&sliding&fricAon&is&about&240&Ames&higher&than&wear&intensity&against&DCTM&without&CVDFdiamond.&
• FricAon&coefficient&in&dry&sliding&fricAon&for&silicon&carbide&against&DCTM&sample&is&smaller&than&against&DCTM+CVDFdiamond&(fDCTM=0,1F0,15,&fDCTM+CVD=0,11F0,48).&
31&
Surface$structure$of$DCTM$(20x20$mkm)$
32&
Surface$structure$of$CVD>diamond$(20x20$mkm)$
33&
Surface$structure$of$sample$(closeup)$
34&
500x350mkm&
From&previous&two&slides&we&can&conclude&that&the&porosity&and&roughness&of&CVDFdiamond&is&smaller&
than&that&of&DCTM&matrix.&
DCTM&matrix&
CVDFdiamond&&
Main$conclusions$
1. DCTM+CVDFdiamond&insert&samples&showed&beSer&performance&than&DCTM&samples.&
2. The&results&of&the&present&study&may&have&a&substanAal&importance&for&the&development&of&drilling&tools&(core&drill&bits).&
35&