【正文】 pressure. It is plicated to calculate large amount of pressure loss. Therefore, the site operator can adapt a simple method. Only by lifting the bit a little bit from the bottom, the reading on the pressure gauge of main pipe shall be the mentioned total pressure loss at the rated flow rate. 6. Application When selecting the screw drill and its bination, you should work out drilling program, fully consider hole size, hole trace, bit type, specification, formation structure and hydraulic calculation. Surface Checking Before Tripping in Except lifting the connections between nipple and bypass valve, other connections on shell of screw drill shall be coated with locking agent. Assembly bit on the handling device, Counter clockwise rotate the drive shaft ends only with chain wrench to protect the inside threads from loosening . Hoist lifting sub and put screw drill into turntable and bypass valve into the center in easy watch position. And then clamp tightly screw drill with slips, and disassembly lifting sub. Check bypass valve: Press downward the valve stem with hammer handle or wood stick. Fill water from the top into the valve ,there should no leakage from the valve and no great drop of water level .And then loosen the stick, the valve stem is springed up to its original position. The filled water shall flow out evenly from the side holes. This is normal . 6． 1． 5 Connect and low down the kelly. Put bypass valve under the kelly in easy watch position. Start pump, and gradually increase flow rate till bypass valve is closed. Lift the screw drill to watch bit rotating. Now bypass valve is in ―close‖ position. 上海奧森油田服務(wù)有限 公司 Shanghai Ocean Oilfield Service Co. Downhole Motor 12 不應(yīng)有鉆井液從旁通孔流出，檢查的目的僅是看鉆頭是否旋轉(zhuǎn)，不必持續(xù)很長時間，操作過程中應(yīng)避免鉆頭與井口防噴器、井口管線接觸、碰撞。對于現(xiàn)場操作者來說可以采用一種簡便的做法，只要將鉆頭稍稍提離井底，在額定排量下，主管壓力表上的讀數(shù)值就是上述總壓力損失值。如果泵壓表突然增加了幾兆帕，繼續(xù)增加鉆壓 ，泵壓不再增加，這說明鉆具發(fā)生了泄漏，此時鉆具定子與轉(zhuǎn)子間密封破壞，鉆井液通過破壞的馬達密封腔從鉆頭水眼中流出。C of maximum temperature。 我公司生產(chǎn)兩種定子。改善傳動軸的穩(wěn)定性，例如加穩(wěn)定器，對提高鉆具壽命發(fā)揮鉆頭性能是有幫助的。 (2) Formation Edge Structure。 5． 4 使用鉆頭的選擇：與螺桿鉆具一起使用的鉆頭在選擇上是十分重要的問題。 5． 3 對鉆井液的要求：螺桿鉆具的馬達為容積式，決定鉆具性能的因素是馬達的輸入流量和作用于兩端的壓力 降，而不是鉆井液的類型。我公司制造的鉆具傳動軸總成有兩種結(jié)構(gòu)： （ 1） 鉆頭水眼壓降為 ，采用硬質(zhì)合金徑向軸承和中間有一組推力軸承的傳動軸總成（如圖 5）； （ 2） 鉆頭水眼壓降為 ，采用硬質(zhì)合金徑向軸承和金剛石復合片（ PDC）的平面止推軸承，其壽命更長、承載能力更高。 流經(jīng)馬達密封腔的流量為 Qm，通過馬達噴咀的流量 Qz。 馬達的輸出扭矩與馬達的壓降成正比，輸出轉(zhuǎn)速與輸入泥漿量成正比，隨著負載的增加，鉆具的轉(zhuǎn)速有所降低，因此在地面只要根據(jù)壓力表控制壓力，根據(jù)流量計控 制泵的流量，就可以控制井下鉆具的扭矩和轉(zhuǎn)速。 馬達轉(zhuǎn)子的螺旋線有單頭和多頭之分（定子的螺旋線頭數(shù)比轉(zhuǎn)子多 1）。當泥漿流量和壓力達到標準設(shè)定值時，閥芯下移，關(guān)閉旁通閥孔，此時泥漿流經(jīng)馬達，把壓力能轉(zhuǎn)變成機械能。 本手冊主要介紹螺桿鉆具的 性能和使用要 求以及注意事項，便于用戶更好地了解我公司 的鉆具，結(jié)合鉆井的需要，選好、用好、維護好鉆具，發(fā)揮其應(yīng)有的技術(shù)性能，提高鉆井經(jīng)濟效益。定子是在鋼管內(nèi)壁上壓注橡膠襯套而成。圖 3是幾種典型馬達配合的截面輪廊： Bypass Valve Assembly It has two positions of bypass and close (). It is in bypass position during trip operation, circulates mud fluid in the drill string into the annular space bypassing the idle motor, so that no mud may spray out onto the platform during the trip operation. When mud flow rate and pressure reach the setting value, the valve stem moves down and closes the valve. Meanwhile, mud stream flows through the motor, and converts the pressure energy into mechanical energy. As mud flow rate is too low, or mud pump stops, and as the created pressure is not enough to overe spring force and static friction force, the spring presses the stem upward ,and bypass is in open position. Motor Assembly It consists of stator and rotor. Stator is made by squeezing rubber sleeve on the wall of steel tube. There forms spiral structure with a certain geometric parameter. Rotor is a cromeplated screw rod. Stator and rotor matches with each other, to form spiral line and seal cavity through their guide rail difference. With rotor running in the stator, the seal cavity is moving along its axial direction, continuously forms and disappears ,to plete its energy conversion. This is the basic principle of screw drill. Spiral seal line on rotor is divided into single end and multiend ( stator with one more end than rotor). The less ends the motor has, the higher speed and the lower torque is. The more ends it has, the lower speed and the higher torque is. shows the sectional profile of several typical motors. 上海奧森油田服務(wù)有限 公司 Shanghai Ocean Oilfield Service Co. Downhole Motor 3 馬達定子一個導程組成一個密封腔，也稱為一級。如果流量過大，轉(zhuǎn)子會超速運轉(zhuǎn)，定子和轉(zhuǎn)子會出現(xiàn)提前損壞，如果流量過小，馬達將停止轉(zhuǎn)動。 Based on the above remended equation, the customers can timely change different diameter nozzles according to the actual demand, so as to reach ideal effect. 上海奧森油田服務(wù)有限 公司 Shanghai Ocean Oilfield Service Co. Downhole Motor 6 3． 3 萬向軸總成 萬向軸的作用是將馬達的行星運動轉(zhuǎn)變?yōu)閭鲃虞S的定軸轉(zhuǎn)動，將馬達產(chǎn)生的扭矩及轉(zhuǎn)速傳遞給傳動軸至鉆頭。BH(渤海 )。 of Screw drill is ?165mm。 什么樣的地層結(jié)構(gòu)、地層 軟硬、使用哪類鉆頭、用什么樣的刃部設(shè)計，請參考有關(guān)鉆頭的專業(yè)資料，這里僅就使用螺桿鉆具完成各種鉆井作業(yè)，對鉆頭的選擇作些簡要說明。 (5) Estimation of Bit and Screw Drill Running Life。 5． 5 對井底環(huán)境溫度的要求：溫度過高對鉆具馬達性能十分不利，會使所有不利 因素加劇。 5． 6 對鉆井液流量的要求：螺桿鉆具特點之一，輸出轉(zhuǎn)速與輸入鉆井液流量成正比。C of maximum temperature. Requirement for Flow Rate of Drilling Fluid: One of the screw drill features is that the output speed is proportional to the input flow rate of drilling fluid