的有效工作流量范围，建议按推荐 参数进行选择，否则会降低钻具的 工作效率和使用寿命。
的有效工作流量范围，建议按推荐 参数进行选择，否则会降低钻具的 工作效率和使用寿命。
5. 7钻井液压力与钻压的特点：钻 具进行空运转时，若保持泥浆流量 不变，钻具与钻头的压降为一个常 数，该值随钻具型式和规格的不同 而有所不同。钻具工作时，随着钻 压逐步增加，钻井液循环压力逐渐 上升，该压力的增量与钻压或钻进 所需扭矩的增量成正比，当达到最 大推荐值时，产生最佳扭矩。继续 增加钻压，当循环钻井液在马达两 端产生的压降超过最大设计值时， 钻具将发生泄漏。正常工作时，表 压随钻压的增减而升降。如果泵压 表突然增加了几兆帕，继续增加钻 压，泵压不再增加，这说明钻具发 生了泄漏，此时钻具定子与转子间 密封破坏，钻井液通过破坏的马达 密封腔从钻头水眼中流出。当因故 障卡钻时，钻井液在钻具制动情况 下，仍可以继续循环流过钻具。一 旦钻具发生制动，应迅速将钻具提 离井底降低钻压，因为钻井液长时 间流过不转的马达会使钻具严重损 坏。
另外，要使钻具获得最佳工作 效率，应将钻具两端的压差控制在 推荐参数范围内。
5. 8预先进行必要的水利计算：钻 井作业时，由泥浆泵泵岀的钻井液 依次经立杆、水龙头、方钻杆而进 入钻杆、钻铤、无磁钻铤、钻具（马 达）、钻头水眼及环空而返回地面。
在钻井液不断循环过程中，由于钻 井液本身的摩擦和钻井液与管壁、
rate. It is advised to choose the range according to the recommended parameters. Otherwise, it may shorten the screw drill ' s working efficiency and running life.
Features of Drilli ng Fluid and Drilli ng Weight: When screw drill is in idle working condition, if keeping fluid flow rate un cha nged, the pressure loss caused by both bit and screw drill shall be a constant value. This value changes with the differenee of drill model and specification. As screw drill is running, fluid recycling pressure will gradually in crease with gradual rise of drilli ng weight. The in creme nt of pressure is proporti onal
to the torque in creme nt n eeded by drilli ng weight and stripp ing in. When it reaches the maximum recomme nded value, optimum torque shall be produced. If drilling weight goes on rising, whe n the pressure loss of recycli ng fluid at both ends of motor is over maximum desig n value, leakage shall occur from the screw drill. In normal operation, the gauge pressure rises with the drilling weight up and down. If the gauge shows sudden rise of temperature to several Mpa, when the drilling weight goes on in creas ing, pump pressure shall no Ion ger in crease. This in dicates there occurs some leakage from screw drill. The seal between stator and rotor may be changed, and fluid may be flowing out from bit nozzle while going through the damaged seal cavity. When it is stick ing due to this problem, fluid is still recycli ng through screw drill since screw drill brak ing. Once screw drill brakes, it shall be quickly lifted away from the hole bottom to reduce drilling weight, since screw drill may be seriously damaged with fluid flowing through the idle motor for Ion ger time.
Additi on ally, the pressure loss at the bottom ends of screw drill shall be con trolled withi n the recomme nded range, to ensure screw drill in optimum working efficie ncy and running life.
Early Hydraulic Calculation: In drilling operation, the pumped mud flows successively through riser, swivel, kelly into drill pipe, collar, non-mag netic collar, motor ,bit
nozzle and annular space, and upwards to the surface. During recycling, the loss caused from the friction of fluid its own and the friction of fluid onto the pipe wall, hole wall an d/or partial flow will con sume a certa in en ergy.
井壁的摩擦及各局部流动造成的损失，皆 需消耗一定的能量。这一能量损失以压力 损失表现岀来。累加各部分的压力损失后 可计算岀总的压力损失，按预计钻井深度 算岀总压力损失后，就可以作为确定泵压 的一个参数，这种大量的压力损失计算是 很繁琐的。对于现场操作者来说可以采用 一种简便的做法，只要将钻头稍稍提离井 底，在额定排量下，主管压力表上的读数 值就是上述总压力损失值。6
井壁的摩擦及各局部流动造成的损失，皆 需消耗一定的能量。这一能量损失以压力 损失表现岀来。累加各部分的压力损失后 可计算岀总的压力损失，按预计钻井深度 算岀总压力损失后，就可以作为确定泵压 的一个参数，这种大量的压力损失计算是 很繁琐的。对于现场操作者来说可以采用 一种简便的做法，只要将钻头稍稍提离井 底，在额定排量下，主管压力表上的读数 值就是上述总压力损失值。
6.钻具的使用方法
在选择钻具及其组合方案时，应制定 钻井作业计划，充分考虑井眼轨迹、钻头 类型、规格、地层结构和水利计算等细节。
6. 1钻具下井前的地面检查；
6. 1. 1钻具除提升短节与旁通阀连接外， 其他部分的壳体连接均涂以锁紧剂。
6. 1. 2用钻头装卸器把钻头装上，只许 用链钳转动钻具传动轴头，而且只能逆时 针旋转（俯视旋向，下同），以防止内部螺 纹松扣。
6. 1. 3吊起提升短节，把钻具放入转盘 中，把旁通阀置于转盘中易于观察的位置。
用卡瓦把钻具卡牢，卸去提升短节。
6. 1. 4检查旁通阀：用锤柄或木棒向下 压旁通阀芯，从上部向旁通阀注满水，此 时旁通阀应不漏，水面无明显下降，然后 挪走木棒，阀芯应被弹簧弹起复位，所注 水应从侧面各孔均匀流出，即可认为正常。
6. 1. 5接方钻杆并下放，使旁通阀位于 钻杆下方便于观察的地方，开动钻井泵， 逐渐提高排量直到旁通阀关闭，上提钻具, 看钻头是否转动，此时旁通阀处于“关闭” 位置。
Application
When select ing the screw drill and its comb in ati on, you should work out drilling program, fully consider hole size, hole trace, bit type, specification, formation structure and hydraulic calculati on.
Surface Check ing Before Tripp ing in
Except lifting the connections between nipple and by-pass 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 by-pass valve into the center in easy watch position. And then clamp tightly screw drill with slips, and disassembly lifting sub.
Check by-pass valve: Press dow nward the valve stem with hammer han dle 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 the n loose n 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 no rmal .
6. 1. 5 Connect and low down the kelly. Put by-pass valve under the kelly in easy watch position. Start pump, and gradually in crease flow rate till by-pass valve is closed. Lift the screw drill to watch bit rotati ng. Now by- pass valve is in
“ close ” position.
不应有钻井液从旁通孔流岀， 检查的目的仅是看钻头是否旋转， 不必持续很长时间，操作过程中应 避免钻头与井口防喷器、井口管线 接触、碰撞。停泵后注意观察旁通 阀是否再次打开，使钻井液从旁通 孔排岀。泵未完全停止之前，不要 把旁通阀提到转盘以上，防止污染 井台。
不应有钻井液从旁通孔流岀， 检查的目的仅是看钻头是否旋转， 不必持续很长时间，操作过程中应 避免钻头与井口防喷器、井口管线 接触、碰撞。停泵后注意观察旁通 阀是否再次打开，使钻井液从旁通 孔排岀。泵未完全停止之前，不要 把旁通阀提到转盘以上，防止污染 井台。
6.
6. 1. 6卸下方钻杆，按设计的钻具 组合，分别把弯接头、无磁钻铤、 稳定器等接好。将弯接头拧入旁通 阀之前，如果用斜口管鞋座造斜， 应检查造斜键，保证斜口管鞋座处 于正常的工作位置，并保证与接头 的弯头刻线对准。
在所有钻具组合及钻杆连接过 程中，注意防止粘扣错扣。为防止 操作中移扣，建议装卸过程中应牢 记：钻头接头相对于壳体的旋向为 俯视反时针方向。违反此项规定， 如反向转动转盘或用转盘旋紧马达 以上的扣等，就会造成钻具内部零 件的松扣或脱扣，请用户注意。
6. 2把钻具及其组合下到井眼里： 尽管钻具本身外形简单，且有足够 的刚性，司钻下放钻具时，仍需控 制下放速度，否则易被井眼中的沙 桥、井眼台肩、套管鞋所损坏。遇 有这样的井段，往往需开动钻井泵， 慢慢地扩大井眼再通过。
如果用弯接头或弯壳体，钻头 侧面就更容易碰上井壁的硬岩层和 套管鞋等，因此要周期性的转动钻 具组合，以消除侧钻的影响。
对于深井和高温井，下放钻具 时建议周期性地进行中途循环，这 样可以防止钻头堵塞，或因高温造 成钻具定子损坏。
There should be no fluid flowing out of by-pass hole. To do this is only for checking bit rotation. It should not last Ion ger. In the operati on, it should preve nt the bit from touching wellhead blowout preventer and flow line. After pump stops, check by-pass valve in ope n positi on or not, and fluid flowing out of by-pass valve or not. Do not lift the valve over turn table un til pump completely stops as to protect the platform from polluti on
16.1.6 Disassembly kelly and combine the screw drill in accorda nee with the program. Conn ect bent sub, non-mag netic collar and stabilizer etc. separately . If you make deflect ion with muleshoe, before twisting bent sub into by-pass valve, you should exam ine deflect ing key to en sure muleshoe sitt ing in normal working position, and align the sc
