PDC鉆頭設(shè)計基礎(chǔ)
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1、CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.PDC鉆頭設(shè)計理念介紹 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.理解鉆頭剖面結(jié)構(gòu)剖面結(jié)構(gòu)
2、對鉆頭性能的影響后倒角特點力平衡設(shè)計切削結(jié)構(gòu)特點新的設(shè)計軟件的應(yīng)用 - IDEAS內(nèi)容 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.鉆頭剖面鉆頭剖面直接影響到以下性能:鉆頭穩(wěn)定性鉆頭導(dǎo)向性布齒密度鉆頭壽命 ROP清洗和冷卻效果注:鉆頭的剖面設(shè)計必須與鉆井環(huán)境需要相匹配 CONFIDENTIAL: For Internal Use Only . May not be
3、disclosed, used or reprodu ced without written permission from S mith International, Inc.鉆頭剖面結(jié)構(gòu)組成 鉆頭剖面包括:頂點錐形面鼻部肩部 外徑弧面保徑部分頂點 錐形面鼻部保徑部分外徑弧面肩部 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.錐面角頂點 鉆頭的幾何中心點錐面 通常用
4、角度來表示特點:深錐面 (90)淺錐面 (150) CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.深錐面特點 優(yōu)點:較高的穩(wěn)定性中心區(qū)域的金剛石覆蓋率大不足之處:導(dǎo)向性不好;清洗效果不好;攻擊能力低。 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced with
5、out written permission from S mith International, Inc.淺錐面特點:優(yōu)點:導(dǎo)向性強(qiáng);清洗效果好;攻擊性強(qiáng)。不足之處:穩(wěn)定性差;金剛石覆蓋率低。 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.鼻部位置定義 鼻部定義L R CONFIDENTIAL: For Internal Use Only . May not be
6、disclosed, used or reprodu ced without written permission from S mith International, Inc.鼻部曲面特點 大曲面 (R):通過大的表面面積來達(dá)到很好的抗沖擊能力,適合在硬且夾層多的地層中使用。小或稱尖曲面 (r):可在切削片上形成較高的點式?jīng)_擊,適合于軟且均質(zhì)性好的地層。得到較高的ROP. Rr CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission f
7、rom S mith International, Inc.鼻部與中心距離的關(guān)系鼻部與中心距離小可提供給肩部更大的表面面積和布齒密度,適合軟但是研磨性強(qiáng)的地層鼻部與保徑部位距離近可給鉆頭冠部提供更大冠面面積 從而得到更好的沖擊能力, 適合比較硬的地層LL CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.肩部,外徑曲面和保徑肩部從鼻部外緣線到過渡面的曲面部分。外徑曲面 “
8、外徑曲面” 保持肩部和保徑部分之間光滑的曲面。保徑有助于鉆頭穩(wěn)定和保持井眼尺寸。 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.鉆頭冠面的類型4 種常規(guī)類型:平拋面短拋面中拋面長拋面平拋面常用在較硬且研磨性弱的地層;而長拋面常用在較軟而且研磨性很強(qiáng)的地層。 CONFIDENTIAL: For Internal Use Only . May not be disclos
9、ed, used or reprodu ced without written permission from S mith International, Inc.平拋面應(yīng)用:硬,非研磨性地層 (Ej.: L石灰?guī)r,白云巖) 強(qiáng)力定向作業(yè)鉆頭冠面的類型 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.應(yīng)用: 硬且中等研磨性地層 (Ej.: Calcareous sand
10、stone, limestone, cherts) 典型的定向作業(yè)短拋面鉆頭冠面的類型 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.應(yīng)用:中硬到硬且研磨性強(qiáng)的地層 (i.e.: Sandstone, limestone, hard shales) 轉(zhuǎn)盤或是馬達(dá)鉆井作業(yè)中拋面鉆頭冠面的類型 CONFIDENTIAL: For Internal Use Only . M
11、ay not be disclosed, used or reprodu ced without written permission from S mith International, Inc.應(yīng)用: 軟且研磨性地層 (i.e.: 硅質(zhì) shales, silicious clays) 適合轉(zhuǎn)盤鉆進(jìn)長拋面鉆頭冠面的類型 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc
12、.鉆頭冠面的類型短拋面中拋面平拋面長拋面 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.后倒角 這個角度的大小決定了PDC切削片攻擊地層的能力。大后倒角可以提高抗沖擊能力和研磨能力。小后倒角可以提高機(jī)械鉆速。整個鉆頭上使用的后倒率是不一樣的,這樣可以得到不同的目的,比如ROP 和壽命。B.R B.R CONFIDENTIAL: For Internal Use Onl
13、y . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.10 30后倒角攻擊性較強(qiáng),適合于軟地層,可取得很高的機(jī)械鉆速。攻擊性較弱,適合于較硬地層,機(jī)械鉆速低。 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.典型使用的
14、后倒角 后倒角 5 to 10 15 20 30地層硬度特性非常軟的粘土和泥巖。高 ROP適合所有地層。最好的應(yīng)用是在軟地層中shale)適合所有地層切削片壽命長最好是用在研磨性的砂巖地層比較硬的地層 典型的應(yīng)用在保徑部位 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.6 blades / 16mm cutters12.25” M616VPX, ER20091后倒角的
15、布置 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.鉆頭冠面特點切削結(jié)構(gòu)多套切削特點單套切削結(jié)構(gòu) - New IDEAS2力平衡刀翼分布刀翼和保徑幾何形狀Lo-Vibe (可選)特性特殊切削結(jié)構(gòu) (e.g.: ARCS)穩(wěn)定性特性影響因素介紹 CONFIDENTIAL: For Internal Use Only . May not be disclosed, use
16、d or reprodu ced without written permission from S mith International, Inc.震動可能是由于鉆頭的特征產(chǎn)生的。有些特征是可見的,而有些是不可見的??梢姷奶卣靼ǎ旱兑硇螤詈筒贾茫叫螤?,低磨阻塊等;不可見特征包括:力平衡,復(fù)合片性能和結(jié)構(gòu)等。加強(qiáng)穩(wěn)定性特征切削結(jié)構(gòu) CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith Internation
17、al, Inc.定義:通過獨(dú)特的設(shè)計,來布置PDC 復(fù)合片從而達(dá)到預(yù)期的性能和壽命。目標(biāo):通過獨(dú)特的井底覆蓋模式來滿足不同的需求(硬度,研磨性,潛在的震動等) ,達(dá)到用戶滿意。切削結(jié)構(gòu) CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.鉆頭的性能和鉆井效率直接受切削齒的布置類型影響。 多種布齒特點可能達(dá)到理想的性能和壽命的目的。切削結(jié)構(gòu) CONFIDENTIAL: For
18、 Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.主要有兩種 類型:切削結(jié)構(gòu)的類型 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.最早期的和最常用的切削齒布置模式。切削齒沿著剖面
19、分布,已達(dá)到完全的覆蓋井底。這種布置結(jié)構(gòu)就是單一模式,是每一顆齒都有獨(dú)自的運(yùn)動軌跡。單一模式 1 1 1 1 1 1 1 1 切削結(jié)構(gòu) CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc. CL r1 1 2 3 4 5 6 . 切削結(jié)構(gòu) CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or
20、reprodu ced without written permission from S mith International, Inc.順時針旋轉(zhuǎn)逆時針旋轉(zhuǎn)單一模式布置類型 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.順時針旋轉(zhuǎn)逆時針旋轉(zhuǎn)單一模式布置類型 CONFIDENTIAL: For Internal Use Only . May not be discl
21、osed, used or reprodu ced without written permission from S mith International, Inc.順時針旋轉(zhuǎn)逆時針旋轉(zhuǎn).單一模式布置類型 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.順時針旋轉(zhuǎn)比逆時針旋轉(zhuǎn)類型穩(wěn)定性要差,很難達(dá)到要求的穩(wěn)定性。攻擊性相對較強(qiáng)。逆時針旋轉(zhuǎn)非常好的穩(wěn)定性。攻擊性比順時針
22、旋轉(zhuǎn)設(shè)計要弱。單一模式布置類型 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.Rh1 Rh2切削結(jié)構(gòu) CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International,
23、Inc.鉆頭的性能(穩(wěn)定性)和鉆井效率(ROP)都直接的受切削齒布置得影響。在實際使用中,切削齒的不同的布置方式可能起到鉆頭性能和壽命的最佳效果。多元化切削齒的布置切削結(jié)構(gòu) CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.所謂多元是指多套的切削齒結(jié)構(gòu);其中每一套都包含了一系列的切削齒在每一套中的切削齒都有其各自的運(yùn)動軌跡 Plural SetSingle Set 2 2
24、 2 33 5 7 101 1 1 11 1 1 11 3 5 72 4 6 8CL Gauge111 1 9 10 切削結(jié)構(gòu)多元化切削齒的布置 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.多元化的布置會形成比單一模式的更明顯的脊結(jié)構(gòu) Plural SetCn = 2Single SetCn = 1 2 4 6 81 3 5 72 4 6 8 切削結(jié)構(gòu)多元化切削齒的
25、布置 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.力平衡切削結(jié)構(gòu) CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.切削結(jié)構(gòu)力平衡 CONFI
26、DENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.切削齒的分布和定位徑向位置指鉆頭中心到復(fù)合片面中心點的距離 。傾角指復(fù)合片沿著鉆頭剖面方向與鉆頭軸線垂直向的夾角。R.P I.A 力平衡 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written pe
27、rmission from S mith International, Inc.角位置如圖所示,鉆頭的 0基準(zhǔn)線和通過復(fù)合片面中心線的角度側(cè)倒角指復(fù)合片面部延長線和通過鉆頭中心線的夾角。A.P Ref. S.R0 力平衡 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.縱向位置從基準(zhǔn)水平線到復(fù)合片面中心線間的垂直距離。0 REF. L.P所有的上述數(shù)據(jù)輸入電腦程序,將有
28、助于利用先進(jìn)的軟件來模擬每一顆切削齒與地層的切削模式和受力分析。力平衡 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.061s75.cfb size_type blade 1 0.1962 17.00 2.3383 -20.00 15.00 0.00 0.6250 13X10ANG1 1 2 0.4273 224.20 2.4224 -20.00 16.00 0.00
29、 0.6250 13X10ANG1 3 3 0.7336 13.10 2.5339 -20.00 17.00 0.00 0.6250 13X10ANG1 1 4 0.9742 223.90 2.6214 -20.00 18.00 0.00 0.6250 13X10ANG1 3 5 1.1783 159.60 2.6954 -18.98 19.00 0.00 0.6250 13X10ANG1 4 6 1.4620 9.20 2.7604 -6.80 20.00 0.00 0.6250 1613 1 7 1.4620 63.20 2.7604 -6.80 20.00 0.00 0.6250 13X
30、10ANG1 5 8 1.7879 223.60 2.7604 6.80 20.00 0.00 0.6250 1613 3 9 1.7879 300.80 2.7604 6.80 20.00 0.00 0.6250 1613 2 10 2.1047 155.70 2.6837 20.42 20.00 0.00 0.6250 1613 4 11 2.3945 5.30 2.5346 34.03 20.00 0.00 0.6250 1613 1 12 2.3945 62.90 2.5346 34.03 20.00 0.00 0.6250 1613 5 13 2.6411 223.30 2.3215
31、 47.64 20.00 0.00 0.6250 1613 3 14 2.6411 298.10 2.3215 47.64 20.00 0.00 0.6250 1613 2 15 2.7989 151.80 2.1112 58.39 21.00 0.00 0.5290 1313 4 16 2.9223 1.40 1.8788 65.58 22.00 0.00 0.5290 1313 1 17 2.9223 62.60 1.8788 65.58 22.00 0.00 0.5290 1313 5 18 3.0161 223.00 1.6329 72.67 23.00 0.00 0.5290 131
32、3 3 19 3.0161 295.40 1.6329 72.67 23.00 0.00 0.5290 1313 2 20 3.0713 147.90 1.4166 78.70 24.00 0.00 0.5290 1313 4 21 3.1035 357.50 1.1957 84.72 25.00 0.00 0.5290 1313 1 22 3.1035 62.30 1.1957 84.72 25.00 0.00 0.5290 1313 5 23 3.1125 222.70 0.9626 90.08 25.00 0.00 0.5290 1313 3 24 3.1125 292.70 0.962
33、6 90.08 25.00 0.00 0.5290 1313 2 25 3.0850 144.00 0.7741 90.01 30.00 0.00 0.5290 1313PF 4 26 3.0850 353.60 0.5857 90.00 30.00 0.00 0.5290 1313PF 1 27 3.0850 62.00 0.5857 90.00 30.00 0.00 0.5290 1313PF 5 28 3.0850 222.40 0.3972 90.00 30.00 0.00 0.5290 1313PF 3 29 3.0850 290.00 0.3972 90.00 30.00 0.00
34、 0.5290 1313PF 2 力平衡切削齒序號徑向位置圓周角齒高剖面角度后倒角側(cè)倒角復(fù)合片尺寸復(fù)合片尺寸刀翼號 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.復(fù)合片受力圖Fv = Vertical Force (WOB)Fc = Circumferential Force (RPM)Fr = Radial ForceFn = Normal Force (Resul
35、tant) .力平衡 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.切削的形狀切削地層形成的形狀對鉆頭的穩(wěn)定性有影響。對稱切削 (理想狀態(tài)) 沒有偏離的作用力產(chǎn)生 (徑向力).非對稱的切削形狀會產(chǎn)生使鉆頭產(chǎn)生偏心運(yùn)動偏離作用力Fn1 Fn2 Fc2Fc1Fr 1 Fv1 Fn Fv2 Fr2 力平衡 CONFIDENTIAL: For Internal Use Onl
36、y . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.非對稱的切削形狀Fn2Fc2Fv2 Fr 2Fn1Fc1Fr1 Fv1 Fn 力平衡 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.欠平衡力隨著鉆頭的工作,鉆壓作
37、用在切削齒上,總扭矩也就通過所有轉(zhuǎn)動力(FC)產(chǎn)生了。 Fc FcFr Fr Fc FcFrFrrWOB WOB XX 力平衡 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.所有的徑向力和轉(zhuǎn)動力累加起來就決定了欠平衡力的大小和方向。兩個欠平衡力的合力就是總的欠平衡力。力平衡 CONFIDENTIAL: For Internal Use Only . May not b
38、e disclosed, used or reprodu ced without written permission from S mith International, Inc.直刀翼和螺旋刀翼刀翼的形狀和布置對減少鉆頭震動,有一定的影響。螺旋刀翼ai a i+1直刀翼 刀翼形狀 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.直刀翼和螺旋刀翼對于直刀翼來說,切削齒
39、的徑向力完全累加到了保徑上。而螺旋刀翼,僅是部分的徑向力作用在了保徑上,是比直刀翼的影響小的。 Fr1 Fr2 Fr3 Fr4 Fr5 Fr6Fr1 Fr2 Fr3 Fr4 Fr5 Fr6 S FriS Fri cos aiS FriS Fri cos ai 刀翼形狀 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.直刀翼和螺旋刀翼(cont.)較低的保徑應(yīng)力減小了鉆頭
40、隨保徑本身轉(zhuǎn)動的幾率。同時,因為轉(zhuǎn)動而產(chǎn)生的震動破壞了也降低到了最小化。刀翼形狀 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.螺旋刀翼減小保徑所受應(yīng)力,最小化震動發(fā)生,提高穩(wěn)定性。是保證力平衡的主要結(jié)構(gòu)。刀翼形狀 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu c
41、ed without written permission from S mith International, Inc.對稱 與 非對稱對稱刀翼是指在相鄰的兩個刀翼之間的角度是相等的。由于是對稱的,產(chǎn)生的震動是重復(fù)的且不斷擴(kuò)大Rs刀翼布置 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.對稱 與 非對稱非對稱刀翼,通常是相鄰的兩個刀翼間的所夾的角度是不同的。和聲被打破
42、,兩個信號之間的間隔時間是最大的。Ru刀翼布置 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.“Lo-Vibe” (可選)ROP = DOC x RPM DOC = ROP/RPM d max DOC Lo-Vibe CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu
43、ced without written permission from S mith International, Inc.1) 地層的特性與鉆頭剖面的對應(yīng)關(guān)系.A. 軟且研磨性 1. 短拋 B. 硬但沒有研磨性 2. 中拋C. 中軟且沒有研磨性 3. 平拋 D. 中到硬且有研磨性 4. 長拋2) 判斷:刀翼的形狀, lo-vibe和力平衡 是可見的穩(wěn)定性特征。T F回顧 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from
44、S mith International, Inc.3) Indicate Forces on a PDC cutter:A. Radial force; B. Normal force; C. Circumferential force; D. WOB.回顧 CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.回顧4) Indicate the plurality of the PDC bit shown below: Plurality: _ - _ - _ CONFIDENTIAL: For Internal Use Only . May not be disclosed, used or reprodu ced without written permission from S mith International, Inc.5)下圖反映了鉆頭的攻擊性: 1. 弱; 2.中等; 3. 強(qiáng) 3015 20 回顧
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