常規(guī)式游梁抽油機(jī)設(shè)計【三維SW圖】【含7張CAD圖紙+文檔全套】
喜歡就充值下載吧。。資源目錄里展示的文件全都有,,請放心下載,,有疑問咨詢QQ:414951605或者1304139763 ======================== 喜歡就充值下載吧。。資源目錄里展示的文件全都有,,請放心下載,,有疑問咨詢QQ:414951605或者1304139763 ========================
前言
目前,采油方式有自噴采油法和機(jī)械采油法。在機(jī)械采油法中,有桿抽油系統(tǒng)是國內(nèi)外油田最主要的,也是至今一直在機(jī)械采油方式中占絕對主導(dǎo)地位的人工舉升方式。有桿抽油系統(tǒng)主要由抽油機(jī)、抽油桿、抽油泵等三部分組成,抽油機(jī)是有桿抽油系統(tǒng)最主要的升舉設(shè)備。根據(jù)是否具有游梁,抽油機(jī)可以劃分為游梁式抽油機(jī)和無游梁式抽油機(jī)。而常規(guī)游梁抽油機(jī)自誕生以來,歷經(jīng)百年使用,經(jīng)歷了各種工況和各種地域油田生產(chǎn)的考驗,經(jīng)久不衰。目前仍在國內(nèi)外普通使用。常規(guī)游梁式抽油機(jī)以其結(jié)構(gòu)簡單、耐用、操作簡便、維護(hù)費用低等明顯優(yōu)勢,而區(qū)別于其他眾多拍油機(jī)類型,一直占據(jù)著有桿系采油地面設(shè)備的主導(dǎo)地位。
游梁式抽油機(jī)的主體結(jié)構(gòu)為曲柄搖桿機(jī)構(gòu)。根據(jù)驢頭和曲柄搖桿機(jī)構(gòu)相對于支架的位置,游梁式抽油機(jī)的機(jī)構(gòu)形式可以劃分為常規(guī)型和前置式兩種;根據(jù)平衡方式的不同,游梁式抽油機(jī)可以劃分為曲柄平衡、游梁平衡和復(fù)合平衡。
常規(guī)型游梁式抽油機(jī)主要由發(fā)動機(jī)、三角皮帶、曲柄、連桿、橫梁、游梁、驢頭、懸繩器、支架、撬座、制動系統(tǒng)及平衡重等組成。
發(fā)動機(jī)安裝在撬座上,其安裝位置有兩種,一種是將發(fā)動機(jī)置于整體尾部,另一種是將發(fā)動機(jī)放在支架下面。
減速箱為二級齒輪傳動減速箱,傳動比為30左右.齒輪型式一般小功率用斜齒,大功率用人字齒。近年來推廣使用點嚙合雙圓弧人字齒。
曲柄一端與減速器輸出軸固結(jié),另一端與連桿鉸接.
連桿與橫梁常見有兩種型式:小型抽油機(jī)多為組焊結(jié)構(gòu),靠改變后臂長度來調(diào)節(jié)沖程.大型抽油機(jī)多為整體機(jī)構(gòu),靠改變曲柄與連桿鉸接位置來調(diào)爺沖程。
游梁由型鋼組焊而成,也有用大型工字鋼整體制造。
驢頭由鋼板組焊而成,有上翻式、側(cè)轉(zhuǎn)式、拆繼式幾種形式。
平衡重為金屬塊。小型抽油機(jī)多裝于游梁尾部,大型抽油機(jī)多裝于曲柄兩翼.平衡重可根據(jù)需要而調(diào)整。
本設(shè)計將對常規(guī)游梁式抽油機(jī)進(jìn)行設(shè)計與計算,以達(dá)到對常規(guī)游梁式抽油機(jī)的優(yōu)化設(shè)計的目的。
目錄
1設(shè)計任務(wù)書 1
1.1課題內(nèi)容 1
1.2設(shè)計內(nèi)容: 1
2總體方案的設(shè)計 2
2.1抽油機(jī)設(shè)計原理的確定 2
2.2桿長尺寸的設(shè)計計算 3
2.4安裝尺寸與機(jī)構(gòu)相關(guān)參數(shù) 3
2.5常規(guī)游梁式抽油機(jī)零部件關(guān)系 3
3游梁抽油機(jī)基本參數(shù)的確定 4
3.1游梁抽油機(jī)的運動分析 4
3.2游梁式抽油機(jī)懸點載荷計算 7
3.3游梁式抽油機(jī)減速箱曲柄軸扭矩計算 10
3.4游梁抽油機(jī)的抽汲工況 12
3.5游梁式抽油機(jī)的電動機(jī)選擇計算 13
4常規(guī)游梁是抽油機(jī)的平衡計算 14
5變速機(jī)構(gòu)的傳動比分配及其結(jié)構(gòu)確定 14
5.1變速機(jī)構(gòu)的傳動比分配 14
6主要部件的設(shè)計 15
6.1曲柄 15
6.2游梁 16
6.3驢頭 17
6.4橫梁 18
6.5常規(guī)游梁抽油機(jī)裝配體 18
參考文獻(xiàn) 19
致謝 20
1設(shè)計任務(wù)書
1.1課題內(nèi)容
(1)主要參數(shù):型號:CYJ3—2.1—13HB
(2)最大載荷:30KN
(3)沖程長度: 1.4,1.7,2.1(單位:m)
(4)沖程次數(shù):6,9,12 (單位:)
1.2設(shè)計內(nèi)容:
(1)總體方案設(shè)計(總體尺寸,四桿機(jī)構(gòu));
(2)運動分析(計算位移、速度、加速度);
(3)動力分析及平衡計算;
(4)主要部件結(jié)構(gòu)設(shè)計、計算;
(5)電機(jī)選擇與油井匹配參數(shù)的確定;
2總體方案的設(shè)計
2.1抽油機(jī)設(shè)計原理的確定
目前,常規(guī)式游梁抽油機(jī)采用的是四桿機(jī)構(gòu)原理。國內(nèi)外使用的游梁式抽油機(jī)四桿機(jī)構(gòu)的循環(huán)主要有一下三種:對稱循環(huán)、近似對稱循環(huán)和非對稱循環(huán)。在此我們采用近似對稱循環(huán)四桿機(jī)構(gòu)。
圖2-1游梁式抽油機(jī)四桿機(jī)構(gòu)原理圖
近似對稱循環(huán)四桿機(jī)構(gòu)主要參數(shù)參考范圍:
(1)傳動角 : 最大傳動角和最小近似對稱于,故 ,。
(2)極位夾角:
(3)游梁最大擺角:
(4)基桿傾斜角:可取 H-G=
(5)
(6)懸點下死點時曲柄初始角:
(7)各桿長之間相對時間限制:,, , ,若,可取,若 。
2.2桿長尺寸的設(shè)計計算
由于最大沖程,所以各個桿長之間存在以下關(guān)系:
由于本設(shè)計的最大沖程,所以,在此取并且取,則其他桿長為:
此外,
式中:R——曲柄半徑,m;
——游梁后臂長度,m;
——游梁前臂長度,m;
——連桿長度,m;
J——基桿長度(從曲柄旋轉(zhuǎn)中心到游梁支點的距離)m;
2.3平衡方式的確定
目前,國內(nèi)外采用的機(jī)械平衡方式主要有:曲柄平衡、游梁平衡和復(fù)合平衡。由于本抽油機(jī)是短沖程、變沖次的工況要求,所以采用曲柄平衡。而曲柄平衡較游梁平衡來說,調(diào)整更加方便。
2.4安裝尺寸與機(jī)構(gòu)相關(guān)參數(shù)
(1)游梁支撐到底座的高度3~6m
(2)執(zhí)行機(jī)構(gòu)的行程速度比系數(shù)1.2
(3)減速器輸出軸中心到底座的高度0.6m
(4)曲柄半徑:0.5~1.2m
2.5常規(guī)游梁式抽油機(jī)零部件關(guān)系
常規(guī)游梁式抽油機(jī)零部件關(guān)系框圖如圖2-2:
圖2-2常規(guī)游梁式抽油機(jī)零部件關(guān)系框圖
3游梁抽油機(jī)基本參數(shù)的確定
3.1游梁抽油機(jī)的運動分析
將四桿機(jī)構(gòu)簡化為曲柄滑塊機(jī)構(gòu)時,作懸點的運動規(guī)律計算。其簡化圖如下
圖3-1 懸點的運動規(guī)律簡化圖
當(dāng)時,游梁與連桿的連接點處于上死點,相對應(yīng)的懸點C處于下死點;當(dāng)時,B處于上死點,相對應(yīng)的懸點C處于上死點
B點的沖程長度
取B點的位移零點,向下為位移的正方向,則任意曲柄轉(zhuǎn)角時B點的位移為: 由三角形OAD可得:
所以,
按二項式定理展開
B點位移 S
為了確定懸點最大加速度,可對對求導(dǎo),并令其等于零,求得取得極值時的角及對應(yīng)的及加速度值
當(dāng),上面方程二無解,在此情況下,按方程一可得加速度極值在處,即上,下死點處。
當(dāng)懸點在也取得極值,對此不再討論。
3.2游梁式抽油機(jī)懸點載荷計算
(一)懸點靜載荷的計算
在此,我們對上死點、下死點、上沖程和下沖程四種情況進(jìn)行計算。
(1)上沖程
在此過程中,游動閥在柱塞上部油柱壓力的作用下關(guān)閉,而固定閥在柱塞下面泵筒內(nèi)、外壓力差作用下打開。由于游動閥關(guān)閉,使得懸點承受抽油桿自重和柱塞上油柱重,這兩個載荷方向都是向下。同時,因為固定閥打開,使得油管外一定沉沒度的油柱對柱塞下表面產(chǎn)生方向向上的壓力。所以,此過程中,懸點靜載荷等于:
——抽油桿材料的密度,kg/m;
——原油的密度, kg/m;
A——抽油桿橫截面面積, m;
A——泵柱塞橫截面面積, m;
L——抽油桿長度或下泵深度,m;
h——泵的沉沒度, m;
——油井中動液面以上(即L-L段液柱),斷面積等于柱塞面積的油柱重,N.
(2)下沖程
游動閥由于柱塞上下壓力差而打開,而固定閥在泵筒內(nèi)外壓力差作用下關(guān)閉。游動閥打開,使懸點只承受抽油桿柱在有中重力。固定閥關(guān)閉,使得油柱重力移到固定閥和油管上。此時,其靜載荷為
(3)下死點
這時,油桿和連桿的載荷都發(fā)生了變化。
油桿在這一瞬間,其載荷發(fā)生了變化,變化量,載荷增減,使得抽油桿拉長,其伸長量等于:
E——鋼材的彈性模量,
油管在這一瞬時載荷也發(fā)生了變化,使得油管縮短,其油管柱縮短量等于:
——油管管壁的橫截面積
這樣一來,雖然懸點帶著柱塞一起往上移動,但是由于油管柱的縮短,使油管柱的下端也跟著柱塞往上移動,柱塞對泵筒還是沒有相對運動,即還不能抽油,一直到懸點經(jīng)過一段距離等于以后,柱塞才開始抽油。
經(jīng)過上述分析,懸點從下死點到上死點雖然走過了沖程長度S,但是因抽油桿柱和油管柱的靜力變形結(jié)果,使得抽油泵柱塞的有效沖程長度要比S小,所以
靜變形的大小等于:
稱為變形分配系數(shù),一般可取0.6~0.9。
(4)上死點
上死點的情況恰與下死點相反。在此不做深入計算。
經(jīng)過分析計算,在上、下沖程內(nèi),懸點靜載荷隨著懸點位移的變化規(guī)律是一個平行四邊形ABCD。
圖3-2 靜力示功圖
(二)懸點動載荷的大小和變化規(guī)律
在井較深,抽油機(jī)沖數(shù)較大的情況下,必須考慮動載荷的影響,動載荷是由慣性載荷和振動載荷兩部分組成的。
(1)慣性載荷
慣性載荷包括抽油桿和油柱兩部分,即F和F,如果略去抽油桿柱和油柱的彈性影響,可以認(rèn)為,抽油桿柱以及油柱各點的運動規(guī)律和懸點完全一致,所以F和F的大小和懸點加速度a大小成正比,而作用方向和后者相反。
F=
F=
——考慮油管過流斷面擴(kuò)大引起油柱加速度降低的系數(shù)
(1)慣性載荷對懸點總載荷的影響
上沖程時,柱塞(或抽油桿)帶著油桿運動,所以上沖程的慣性載荷F為:
F=F
m——表示油柱慣性載荷與抽油桿柱慣載荷的比值,利用式可得
m=
(三)懸點的最大載荷和最小載荷
懸點的最大載荷F和最小載荷F,特別是最大載荷F,特別是最大載荷F是正確設(shè)計和選擇抽油機(jī)和抽油桿以及確定電動機(jī)功率的主要依據(jù)之一。
3.3游梁式抽油機(jī)減速箱曲柄軸扭矩計算
對計算時采用的符號作如下解釋
F——懸點載荷,N;
——曲柄平衡塊重力,N;
——曲柄平衡塊到曲柄旋轉(zhuǎn)中心的距離,m;
——曲柄自重,N;
——曲柄重心到曲柄旋轉(zhuǎn)中心的距離,m;
——連桿所受的拉力,N;
T——連桿力在曲柄切像上的分力,沿曲柄旋轉(zhuǎn)的方向為正值,m;
M——減速箱曲柄軸輸出扭矩,沿曲柄旋轉(zhuǎn)方向為正值,N.m.
為了便于分析,將曲柄平衡塊重力及曲柄自重折算至曲柄銷處,這種折算要保證折算前后對曲柄旋轉(zhuǎn)中心的力矩不變,折算后的等效載荷用來表示。
首先取游梁為研究對象,將諸力對游梁旋轉(zhuǎn)中心取力矩可得連桿力為:
則連桿力在曲柄切向上的分力T為;
取曲柄為研究對象,為提升油井內(nèi)的抽油桿柱和油柱,減速箱曲柄軸輸出扭矩M,曲柄平衡塊重力與曲柄自重的等效載荷所產(chǎn)生的扭矩共同克服切向力T所產(chǎn)生的扭矩,由曲柄平衡條件;Rsin(2
M=
=
上式中的第一項表示是懸點載荷F在曲柄上所產(chǎn)生的扭矩,稱為油井負(fù)荷扭矩;
式中的只取決于抽油機(jī)的幾何尺寸和曲柄轉(zhuǎn)角,其意義為單位懸點載荷在曲柄上所產(chǎn)生的扭矩,將其稱之為扭矩因數(shù),用表示;
式中的為曲柄自重及曲柄平衡重在曲柄軸上所產(chǎn)生的扭矩,稱之為曲柄平衡扭轉(zhuǎn),用表示;
式中——曲柄最大平衡處扭矩,即曲柄處于水平位置()時曲柄自重及曲柄平衡重對曲柄軸所產(chǎn)生的扭矩。
B為抽油機(jī)的結(jié)構(gòu)不平衡重,其值等于連桿與曲柄銷脫開時,為了保持游梁處于水平位置而需要加在光桿上的力。此力向下時B取正值,向上時取負(fù)值。B值可以實測,也可以根據(jù)抽油機(jī)部件的重力計算。
對曲柄平衡抽油機(jī)可得如下公式;
扭矩因數(shù);
最大扭矩我們可以用勒瑪柴諾夫經(jīng)驗公式計算
S——懸點的沖程長度,m;
——曲柄的最大扭矩,N.m;
——懸點的最大載荷,N;
——懸點的最小載荷,N;
3.4游梁抽油機(jī)的抽汲工況
目前,國內(nèi)外游梁式抽油機(jī)的抽汲工況主要分為五種:正常的、長沖程、短沖程、高沖數(shù)的、低沖數(shù)的,五種工況的沖程長度和沖數(shù)的極值見表
表3-1沖程長度和沖數(shù)的極值
抽汲工況
沖程長度
沖程次數(shù)
最大值
最小值
最大值
最小值
正常
1.2
2.4
5
15
長沖程
2.7
6.0
5
15
短沖程
0.3
1.2
5
15
高沖次
0.9
2.4
15
25
底沖次
0.3
1.5
2
5
在我國油田上絕大多數(shù)都采用正常的抽汲工況,但在我國東部主要油田都處于油田開發(fā)中后期,油田含水量上升,因此目前長沖程抽汲工況增加,所以目前國內(nèi)外抽油機(jī)采用的正常抽汲工況和短沖程抽汲工況還能夠滿足不同抽油井的實際要求。綜上所述,我們在此次設(shè)計中還是以正常的為依據(jù)。
3.5游梁式抽油機(jī)的電動機(jī)選擇計算
游梁式抽油機(jī)裝置的特點
(1) 負(fù)荷是脈動的,而且變化大;
(2) 啟動困難,要求有大的啟動轉(zhuǎn)矩;
(3) 所用的電動機(jī)功率不太大,一般不超過40kW,小的只有幾千瓦,但總的數(shù)量大;
(4) 在露天工作,要求電動機(jī)維護(hù)簡單、工作可靠。
結(jié)合工作特點及工況,在此選擇Y系列的三相異步封閉式鼠籠型電動機(jī)。
電動機(jī)額定功率的確定:
電動機(jī)功率與傳遞到減速箱從動軸(曲柄軸)上扭矩關(guān)系式為:
式中M——傳到曲柄軸上的扭矩,N*m;
——電動機(jī)的額定功率,kW;
n——曲柄軸轉(zhuǎn)數(shù)(懸點沖數(shù));
——傳動效率;
——皮帶傳動效率;
——減速箱傳動效率。
則電動機(jī)額定功率計算公式為:
然而,一般抽油機(jī)電動機(jī)按此表選用:
表3-2一般抽油機(jī)電動機(jī)選用表
根據(jù)上表,將電動機(jī)的額定功率范圍確定在=5.5~7.5kW。
電動機(jī)轉(zhuǎn)速的確定
一般抽油機(jī)選用的減速箱傳動比為,帶傳動的傳動比為,一般。這是抽油機(jī)沖數(shù)按最大沖數(shù)12r/min計算。則電動機(jī)的轉(zhuǎn)速為:
我們在這選用Y132M-4
4常規(guī)游梁是抽油機(jī)的平衡計算
下沖程時,驢頭懸點向下走完沖程長度S,游梁的后臂提高,把能力儲存起來。
游梁部件自重抬高的距離為,儲存能量為,曲柄平衡重抬高的距離為,儲存的能量為,曲柄自重抬高的距離為,儲存的能量為。所以平衡裝置儲存能量Q為
5變速機(jī)構(gòu)的傳動比分配及其結(jié)構(gòu)確定
5.1變速機(jī)構(gòu)的傳動比分配
電動機(jī)型號Y160L-8,其功率為P=7.5轉(zhuǎn)速為N=720則電動機(jī)輸出扭矩.
=99.4796
減速箱參數(shù)
,主動齒輪軸齒數(shù)
.斜齒輪齒數(shù)
,中間齒輪軸齒數(shù)
,人字齒輪齒數(shù)
,電動機(jī)皮帶輪
,電動機(jī)皮帶輪
,電動機(jī)皮帶輪
,減速器大皮帶輪
減速器比:29.75
皮帶輪速比(電動機(jī)配有三個皮帶輪,減速器主動軸上裝有一個大皮帶輪,故有三種速比)
抽油機(jī)的總速比
在每一種速比下,減速箱被動輸出扭矩。
計算結(jié)果表明,其最大值輸出扭矩低于26kN.m。因此,在設(shè)計該機(jī)時,選用Y132M-4電動機(jī),計算結(jié)果其最大輸出扭矩
該機(jī)的沖次分別為:
6主要部件的設(shè)計
6.1曲柄
曲柄是傳遞減速器輸出扭矩的主要部件,所以它必須具有一定的強(qiáng)度和傳動可靠性。曲柄一般可用灰鑄鐵、球墨鑄鐵和鑄鋼制成。在曲柄平衡的抽油機(jī)上,兩件曲柄共同承受的抽油機(jī)的全部載荷,因此要求曲柄有很高的承載能力,同時為了調(diào)整方便和安全,曲柄上沒有導(dǎo)軌、擋塊、刻度線,可以根據(jù)抽油機(jī)工作條件調(diào)整平衡塊位置,使抽油機(jī)保持平衡。擋塊可在緊固的情況下,防止平衡塊不致落下而發(fā)生事故。 此次,在一系列要求下,用QT700-2制成大尺寸常規(guī)普通型曲柄。如圖6-1.
6.1連桿
每臺抽油機(jī)有兩根連桿,它是傳遞力矩的主要受力桿件,其主件可用管材,也可用其他型材如工字鋼、槽鋼等。但一般多用厚壁無縫鋼管制成,在無縫鋼管的兩管端沒有上、下接頭,上、下接頭通過焊接與無縫鋼管連接在一起。上接頭通過連接銷與橫梁連接在一起,下接頭通過兩個螺栓與軸承盒連接在一起,從而完成力矩的傳遞。因此,對于上下接頭與鋼管的焊縫是否能達(dá)到規(guī)定的強(qiáng)度而滿足使用要求就顯得尤為重要。如果兩根連桿中有一根連桿失效,抽油機(jī)變成單臂傳動,很有可能被拉翻,造成嚴(yán)重的生產(chǎn)安全事故。焊縫作為整個連桿的薄弱環(huán)節(jié),都會引起設(shè)計人員高度重視,一般在設(shè)計中對焊縫的形式,焊接工藝條件,要求以及檢驗方法和標(biāo)準(zhǔn)都提出較高的要求和明確的規(guī)定。同時為了保證兩側(cè)連桿傳動平穩(wěn)和傳遞力矩的均衡一致,兩連桿的工作長度必須完全一致,即達(dá)到一定的尺寸公差要求,這一要求通常用專用工藝裝備來保證。
所以,選用直徑為80的熱軋圓鋼為主件,而上下接頭均用QT700-2鑄成。如圖6-2
圖6-1曲柄
圖6-2連桿
6.2游梁
游梁是抽油機(jī)的主要承載部件,承擔(dān)著抽油機(jī)的全部工作載荷,因此必須要有足夠的強(qiáng)度和一定的剛度。
選用工字鋼為主要部件,經(jīng)過鋼板加強(qiáng)后制成。其工字鋼選材為。見圖6-3
6.3驢頭
驢頭用來將游梁前端的往復(fù)圓弧運動變?yōu)槌橛蜅U的垂直直線往復(fù)運動,驢頭的圓弧半徑R應(yīng)等于前臂長度,為了保證在一定沖程長度下,將圓弧運動變?yōu)閼尹c的直線運動,驢頭的圓弧面長度應(yīng)為:
為驢頭懸點的最大沖程。驢頭采用腹板式結(jié)構(gòu)焊接而成,并應(yīng)用側(cè)翻讓位結(jié)構(gòu)進(jìn)行整修時的讓位。詳見圖6-4。
圖6-3游梁
圖6-4驢頭
6.4橫梁
橫梁用HT200鑄造而成,詳見圖6-5
圖6-5橫梁
6.5常規(guī)游梁抽油機(jī)裝配體
參考文獻(xiàn)
[1] 楊永昌、職黎光、賈逢軍,等. 游梁式抽油機(jī)全臺效率測試研究[J]. 石油礦場機(jī)械,1996,25(5):2-5.
[2] 龍以寧. 游梁式抽油機(jī)曲柄銷可靠性討論[J]. 石油礦場機(jī)械,1992,21(5):6-10.
[3] 龐艷華、劉福剛、楊孝君,等. 游梁式抽油用電動機(jī)的節(jié)電措施[J].石油礦場機(jī)械 .2004,33(197):79-81.
[4] 張學(xué)魯、季祥云、羅仁全,等.游梁式抽油機(jī)的技術(shù)與運用.北京:石油工業(yè)出版社.2001年4月.
[5] 韓成才. 石油鉆采設(shè)備[M].西安:陜西科學(xué)技術(shù)出版社.1999年.
[6] 鄔亦炯、劉卓均,等. 抽油機(jī)[M]. 北京:石油工業(yè)出版社,1994.
[7]梁宏寶、伊蓮娜、孫旭東。游梁式抽油機(jī)節(jié)能技術(shù)改造綜述[J]黑龍江 東北石油大學(xué) 2011年2月
致謝
謝謝母校給了我們?nèi)绱撕玫慕虒W(xué)環(huán)境,謝謝各位老師多年來對我的關(guān)照和教誨,謝謝同學(xué)們給我的幫助!謝謝你們!
20
12 屆畢業(yè)設(shè)計
常規(guī)式游梁抽油機(jī)
設(shè)計說明書
學(xué)生姓名 李 軍 斌
學(xué) 號 8011208117
所屬學(xué)院 機(jī)械電氣化工程學(xué)院
專 業(yè) 機(jī)械設(shè)計制造及其自動化
班 級 機(jī)械12-1
指導(dǎo)教師 廖結(jié)安
日 期
塔里木大學(xué)教務(wù)處制
常規(guī)游梁式抽油機(jī)設(shè)計常規(guī)游梁式抽油機(jī)設(shè)計機(jī)械設(shè)計制造及其自動化機(jī)械設(shè)計制造及其自動化12-1李軍斌李軍斌常規(guī)游梁式抽油機(jī)的原理介紹常規(guī)游梁式抽油機(jī)的原理介紹l常規(guī)游梁式抽油機(jī)應(yīng)用的是曲柄搖桿機(jī)構(gòu)原理而在此四桿機(jī)構(gòu)的循環(huán)方式,有以下三種:l對稱循環(huán)、近似對稱循環(huán)和非對稱循環(huán) l原理圖:基本參數(shù)的確定基本參數(shù)的確定l游梁抽油機(jī)的運動分析l游梁式抽油機(jī)懸點載荷計算l游梁式抽油機(jī)減速箱曲柄軸扭矩計算l游梁抽油機(jī)的抽汲工況l游梁式抽油機(jī)的電動機(jī)選擇計算機(jī)構(gòu)運動簡化機(jī)構(gòu)運動簡化l懸點運動規(guī)律簡化圖機(jī)構(gòu)關(guān)系框圖機(jī)構(gòu)關(guān)系框圖游梁式抽油機(jī)主要構(gòu)件的介紹游梁式抽油機(jī)主要構(gòu)件的介紹驢頭驢頭l驢頭用來將游梁前端的往復(fù)圓弧運動變?yōu)槌橛蜅U的垂直直線往復(fù)運動,驢頭的圓弧半徑R應(yīng)等于前臂長度,為了保證在一定沖程長度下,將圓弧運動變?yōu)閼尹c的直線運動,驢頭的圓弧面長度應(yīng)為:l為驢頭懸點的最大沖程。驢頭采用腹板式結(jié)構(gòu)焊接而成,并應(yīng)用側(cè)翻讓位結(jié)構(gòu)進(jìn)行整修時的讓位。曲柄曲柄l曲柄是傳遞減速器輸出扭矩的主要部件,所以它必須具有一定的強(qiáng)度和傳動可靠性。曲柄一般可用灰鑄鐵、球墨鑄鐵和鑄鋼制成。在曲柄平衡的抽油機(jī)上,兩件曲柄共同承受的抽油機(jī)的全部載荷,因此要求曲柄有很高的承載能力,同時為了調(diào)整方便和安全,曲柄上沒有導(dǎo)軌、擋塊、刻度線,可以根據(jù)抽油機(jī)工作條件調(diào)整平衡塊位置,使抽油機(jī)保持平衡。擋塊可在緊固的情況下,防止平衡塊不致落下而發(fā)生事故。此次,在一系列要求下,用QT700-2制成大尺寸常規(guī)普通型曲柄。橫梁橫梁l橫梁是游梁與連桿之間力及運動傳遞的橋梁,它的制作有一下三種:l型鋼直接制成l焊接l鑄造為了使橫梁和連桿的連接點與橫梁和游梁的連接點在同一水平線上,往往將橫梁作成弓形。常規(guī)游梁機(jī)三維模型常規(guī)游梁機(jī)三維模型謝謝觀映!Proceedings of the International Conference BALTTRIB2007 APPLICATION OF A NEW TEST PROCEDURE FOR MECHANICAL TESTING OF HYDRAULIC FLUIDS J. Schmidt, D. Krause Institute for Product Development and Mechanical Engineering Design, Hamburg University of Technology, Germany Abstract: This paper describes a friction and wear test in a newly developed test machine, which was developed at the TU Hamburg-Harburg to investigate the lubricating capability of hydraulic fluids. The aim of the development of the new test procedure is a better representation of the tribological contacts and effects in fluid power machinery. The investigation of the lubrication capabilities of hydraulic fluids using a line contact showed, that a distinction between different fluids regarding their lubrication capabilities can be made, using friction-, wear- and erosion tests (galling). The high reproducibility of the boundary conditions during different tests was achieved by steady design modifications of the test rig and the development of a computer program for fully-automatic control of the test procedure. The developed test machine fulfils the requirements of a simple test procedure and simply shape of test specimen, which could be produced from principally every type of material and production machines, existing in every company that produce fluid power components. Keywords: Hydraulic, fluid, lubrication, testing 1. INTRODUCTION A very important feature of a hydraulic fluid is its potential to separate the surfaces of a loaded tribo-contact and by this to reduce friction and wear in this contact. The most reliable test to investigate the lubricating capability of a hydraulic fluid is the field test, i.e. the application of the fluid under typical operating conditions and for typical operating periods. For many reasons field tests are time consuming and costly, and the operating condition of different applications typically will be very different so that results from one application might not be transferable to another application. This situation leads to the necessity for fluid producers as well as for the producers of hydrostatic machinery to test their product in a laboratory test before they go for a field test. It should be clear that laboratory tests are only helpful if they reproduce the situation in the tribo-contact of the real machine to a high extend. The Institute for Product Development and Mechanical Engineering Design at the Hamburg University of Technology has developed a new test procedure and a test machine to investigate the lubricating capability of hydraulic fluids 1. In future this test possibly can replace the vane pump test according to DIN 51389 2. The aim of the project was to find a test procedure which reproduces the totality of wear relevant tribological effects in hydrostatic machinery as good as possible, using simply shaped test specimen and a test machine, which allows an easy measurement of the mechanical parameters to derive from these friction and wear. The load conditions of the tribo-systems within a hydrostatic machine (contact pressure, type of relative movement) and velocity and destructor and the properties of the contact partners define the parameters in the contact zone (temperature and geometry) which have the main impact on friction coefficient, critical load and wear performance of the tribo-system. The test procedure and test machine was developed by a systematic approach in research projects DGMK 514 3, 514-1 4 and 610 5. 2. PRINCIPAL ARANGEMENT OF THE TEST APPARATUS The aim of the development of a new test procedure was to achieve ? reproducible quantitative test results with high accuracy, ? simple test specimen, which do not require special manufacturing technologies, ? a test procedure which can be automated and ? low energy consumption, small volume of test fluid and short test time. A detailed analysis of the tribo-contacts in hydrostatic machines was the base for a specification for this new test procedure and machine. Using design methodology and systematic design approach a test principal was found, which is shown in Fig. 1. The arrangement of the test apparatus allows the investigation of line contact and area contact. During the research project it was found, that the line contact is the more interesting one and generates data which allow to classify lubricating capabilities of different fluids; this is the reason why the majority of the tests was only using data from the line contact. To quantify the lubricating capability of a hydraulic fluid the following parameters are used: ? pHD,crit critical pressure which leads to adhesive material removal (“galling”), ? Ex,average average friction coefficient in the line contact, ? Vline wear volume of the test specimen slider. The accuracy and the reproducibility of these parameters define to a high extend how good the tested fluids can be classified as low, medium and high lubricating fluids. Exact measurements of the mechanical parameters as speed, torque and pressure, the possibility to calculate contact forces having friction in guiding devices and bearings in the calculation and a sophisticated method to measure and calculate the wear volume at the slider are the basis to achieve adequate results. During the research project a number of design changes have been made with the test machine to improve the accuracy and reproducibility of the measurements. 3. TEST CONDITIONS To define the optimal test conditions for the short term and long term test (short term test is the test for critical load, long term test is the test for friction coefficient and wear volume) a great number of tests were done. During these tests it was found that the starting process for the test is of significant influence on the results of the tests. 3.1 Start procedure The parameters of the starting procedure have to be such that initial damages of the test specimen are avoided and a controlled running in of the line contact is achieved. An automation of this starting procedure lead to a significant improvement of the following tests. 3.2 Short term test procedure Short term tests are used to find the critical pressure pHD,crit, which is the pressure when spontaneous and intensive adhesive material transfer between the sliding contacts starts galling. The pressure on the piston produces a critical pressure within the tribo-contact at which the lubricating film between the contacting services disappears and mixed friction changes to friction of solids. Figure 2 shows the developing of the test parameters versus time for a typical short term test. pistontest specimen slider(line contact)cylinder(excentric)shaft with excentricshaft end test chamber Figure 1. MPH test rig - principal arrangement of the test apparatus 3.3 Endurance test procedure The endurance test is used to find the fluids specific work friction coefficient of the line contact and the volume loss of the test specimen slider. The load of the tribo-contact is constant for all tests; load means the average pressure on the piston which is held constant during the hole test to produce a constant force in the line contact between slider and cylinder (excentric). Figure 3 shows the developing of the test parameters within the endurance test. end ofstart proceduretest duration hpressure over piston PHDbartemperature tribo-contact EXCtemperature tank tankCtorque excentric TEX Nmaverage friction coefficient EX- Figure 3. Typical developing of the test parameters within a endurance test galling“TEX = 0,5beginning ofshort term testend of startproceduretest duration hpressure over piston PHDbartemperature tribo-contact EXCtemperature tank tankCtorque excentric TEX Nmaverage friction coefficient EX- Figure 2. Typical developing of the test parameters within a short term test4. RESULTS FROM COMPLETET TEST SERIES Within the project mineral oil based hydraulic fluids of HL- and HLP-type and synthetic esters of HEES-types were tested; at this time the tests are extended to mineral and ester based multigrade motor oils and gear oils. Main task of the by now completed tests was to demonstrate different lubricating capabilities of these types of fluids as they should be expected for the different types. The most important point was to demonstrate that the results of multiple tests with the same fluid are in a narrow range, i.e. show small deviations from an average value. This paper reports about the test results for six different types of hydraulic fluids, one fluid of HEES-type, three fluids of type HLP and two fluids of type HL. All fluids had corrosion and anti-aging additives, the HEES-type and the HLP-type fluids were equipped with ep- and aw-additive packages in different concentrations. The table in Fig. 4 gives information about the absolute values of the tests of a typical test range. It is important to see that the critical pressure and the average friction coefficient of three test runs are more or less close to an average value while the volume loss of the slider shows bigger deviations for different tests with the same fluid under the exact same conditions. It can also be seen that there is a certain correspondence between critical load, average friction coefficient and volume loss. On the other hand the table shows, that a relative comparison of the fluids lubricating capabilities is not very easy, because a great number of test results have to be taken into account. Therefore a different presentation of the results has been developed, which is also shown in Fig. 4. The diagram shows the isometric presentation of a results base. In this figure the ellipsoids represent the limits of the measured values for the different fluids; all values are referred to the HF-1 fluid as a reference. HF-2(HL)HF-6(HEES)HF-4(HLP)HF-1(HL)HF-3(HLP)HF-5(HLP)rel. friction coefficient %rel. crit. pressure %rel. wear volume % Figure 4. Absolute values and isometric representation of the test results Figure 5 shows the projections of the three dimensional diagram of figure 4 and demonstrate clearly that the measurement with the MPH test rig allow a clear differentiation of not only fluids of different classes but also of fluids within one class. HF-2(HL)HF-6(HEES)HF-4(HLP)HF-1(HL)HF-3(HLP)HF-5(HLP)rel. Reibungskoeffizient %HF-1: reference fluidrel. wear volume %rel. friction coefficient %HF-2(HL)HF-6(HEES)HF-4(HLP)HF-1(HL)HF-3(HLP)HF-5(HLP)HF-1: reference fluidrel. crit. pressure %rel. wear volume %HF-2(HL)HF-6(HEES)HF-4(HLP)HF-1(HL)HF-3(HLP)HF-5(HLP)HF-1: reference fluidrel. friction coefficient %rel. crit. pressure % Figure 5. Projections of the three dimensional diagram (see fig. 4) of the result parameters CONCLUSION The results of a high number of tests within the MPH-project have shown that it is possible to differentiate the lubricating capability of hydraulic fluids with the MPH test rig. With the design improvement of the test rig and the development of a fully automatic test rig control the reproducibility of test results could be improved. Looking to recent tests with the actual test rig it could be seen, that the values for friction coefficient and critical pressure do not differ more than 10% from the average. The wear volume shows bigger deviations within a test sample with a maximum of 15 % which possibly can be reduced by more accurate measurement techniques 6, 7. Reproducibility of test results was a major point for the MPH-project. The achieved accuracies must be seen in comparison to accuracies requirements of other tests which are used to test hydraulic fluids. The vane pump tests and also the FZG-test 8 do not define a minimum number of test runs and no accuracies in the test results. According to the standards in both tests only one test run is necessary for a classification of a fluid. This leads to the conclusion that test results with the MPH test rig and procedure may give better reliable data about the lubrication capability than other test procedures used assuming at minimum 3 test runs per fluid. REFERENCES 1 Kessler, M., Entwicklung eines Testverfahrens zur mechanischen Prfung von Hydraulikflssigkeiten, Dissertation, Fortschritt-Berichte VDI, Reihe 1, Nr. 335, 2000. 2 DIN 51389, Mechanische Prfung von Hydraulikflssigkeiten in der Flgelzellenpumpe, Deutsches Institut fr Normung e.V., Beuth Verlag Berlin, 1982. 3 Kessler, M., Feldmann, D.G., Mechanische Prfung von Hydraulikflssigkeiten, DGMK Forschungsbericht 514, Hamburg, Juli 1999. 4 Kessler, M., Feldmann, D.G., Mechanische Prfung von Hydraulikflssigkeiten II, DGMK Forschungsbericht 514-1, Hamburg, Sept. 2001. 5 Schmidt, J.; Feldmann, D.G.; Padgurskas, Mechanische Prfung von Hydraulikflssigkeiten, DGMK Forschungsbericht 610, Hamburg, 2006. 6 Feldmann, D.G., Padgurskas, J., Analysis of the Lubrication Capabilities of Hydraulic Fluids using a Test Method with Line Contact, Engineering Materials & Tribology 2004, Riga, 23.-24. Sept. 2004. 7 Schmidt, J., Feldmann, D.G., Padgurskas, J., Application of a new test procedure for mechanical testing of hydraulic fluids, 5. International Fluid Power Conference, Vol. 2, p.269-280, Aachen, 20.-22. March 2006. 8 DIN 51354, FZG-Zahnrad-Verspannungs-Prfmaschine, Deutsches Institut fr Normung e.V., Beuth Verlag Berlin, 1990. Author for contacts: Dr.-Ing. Jens Schmidt, Institute for Product Development and Mechanical Engineering Design, Hamburg University of Technology, Denickestrae 17, 21073 Hamburg, Germany. Phone: +49 40 428783131, Fax +49 40 428782296, E-Mail: jens.schmidttu-harburg.de.
收藏