CN2732976Y

CN2732976Y - Downhole hydraulic pumping pressure-reducing drilling tool

Info

Publication number: CN2732976Y
Application number: CN 200420096669
Authority: CN
Inventors: 倪红坚; 韩来聚; 李作会
Original assignee: Drilling Technology Research Institute of Sinopec Shengli Petroleum Administration Bureau
Current assignee: Drilling Technology Research Institute of Sinopec Shengli Petroleum Administration Bureau
Priority date: 2004-10-10
Filing date: 2004-10-10
Publication date: 2005-10-12
Anticipated expiration: 2014-10-10

Abstract

The utility model discloses a downhole hydraulic pumping pressure-reducing drilling tool which is mainly composed of a drill bit connecting short piece, a low-press cavity, an injection nozzle, an injection cavity, a pumping pipe, etc. The principle of the downhole hydraulic pumping pressure-reducing drilling tool is that the injection nozzle on the upper part of a drill bit is used to form a high-speed jet pointing at the upward movement direction of an annulus and driven by the pressure difference between the inner of a drill column and the annulus. A local low pressure is formed on the vicinity of an outlet of the injection nozzle, and the low pressure is acted on the bottom of a well through the pumping pipe plugged straight on the bottom of the well in the drill bit chamber. The head of liquid acted on local detritus is reduced, and the efficiency of breaking rocks and drill is improved.

Description

Shaft bottom waterpower pumped down drilling tool

Technical field

The utility model belongs to the corollary apparatus of oil, gas drilling.

Technical background

Under shaft bottom head of liquid and formation pore fluid action of pressure, the landwaste that the drill bit fractured rock generates is crushed on original position, cut again by bit weight, hindering the new plane of disruption of rock exposes, the decrease in efficiency that the broken rock of drill bit is crept into, therefore can Here it is so-called " chip hold down effect ", reduce " chip hold down effect " and be directly connected to and improve bit speed.Reducing the shaft bottom head of liquid is the key problem in technology that reduces " chip hold down effect ".Under the insufficient balance condition, the practice that bit speed increases substantially has confirmed this conclusion.But present stage full well section the underbalance technology, only be applicable to the part stratum, and this technology to capacity of equipment require high, investment is big, is prone to complex situations such as well is spoilt, well expansion, the condition of large-scale application is still immature.If therefore can reduce head of liquid in the part, shaft bottom, then both can avoid the deficiency of full well section under-balanced drilling technology, can improve brokenly the rock drilling efficiency again, be a feasible way that improves bit speed at present.

Summary of the invention

The utility model is to realize local depression in the shaft bottom just, reduce " chip hold down effect ", improving broken rock drilling efficiency designs, its principle is utilized the driving nozzle on drill bit top, drive by the pressure differential in the drill string and between the annular space, form and point to the high-speed jet of returning direction on the annular space, form local depression in the driving nozzle exit, suction tube by straight cutting shaft bottom in the drill bit chamber, this low pressure is acted on the shaft bottom, head of liquid on the local landwaste is reduced, and broken rock drilling efficiency improves, and the purpose of this utility model provides a kind of shaft bottom waterpower pumped down drilling tool for the scene exactly.

The utility model is achieved like this, it mainly connects pipe nipple by drill bit, low pressure chamber, driving nozzle, ejection cavity, compositions such as suction tube, drill bit connects pipe nipple and axially connects, two ends are processed with screw thread, top and bottom link with drill string and drill bit respectively, connect the pipe nipple middle part at drill bit and be processed with low pressure chamber, the outlet of low pressure chamber is pointed on the annular space and is returned direction, the axis of low pressure chamber connects pipe nipple with drill bit axis is space antarafacial relation, driving nozzle is installed in an end that connects the pipe nipple inwall in the low pressure chamber near drill bit, in the driving nozzle exit, drill bit connects the pipe nipple middle part and is processed with ejection cavity, the axis of ejection cavity and the axes intersect of low pressure chamber, termination near drill bit connection pipe nipple inwall in ejection cavity has suction tube, drill bit internal is stretched in the suction tube lower end, the straight cutting shaft bottom, driving nozzle adopts to be sealed and matched and is installed in the low pressure chamber, because the area of passage of bit nozzle is less, when drilling fluid flows through nozzle, can produce bigger pressure drop, in drill string and between the outside annular space, form pressure reduction, drilling fluid is under the effect of this pressure reduction, quicken through driving nozzle, form and point to the high-speed jet of returning direction on the annular space, exit region at driving nozzle, because the effect of entrainmenting of jet, formed a low-pressure area, this low-pressure area acts on the local shaft bottom of suction tube entrance area through ejection cavity and suction tube, make the head of liquid on the suction tube entrance area landwaste reduce, rolling of landwaste, the difficulty that startup and new catalase face expose descends, drill bit rock-breaking and well-drilling efficient improves, and the amplitude that head of liquid reduces on the landwaste is by adjusting the inside and outside pressure differential of drill string, the flow passage structure of driving nozzle, property of drilling fluid, ejection cavity, the parameters such as relative position of driving nozzle and low pressure chamber obtain.

The utility model influences the Analysis on Mechanism of drilling speed based on " chip hold down effect ", proposition reduces " chip hold down effect " by the head of liquid that reduces on the landwaste of shaft bottom, improve bit speed, and designed special hydraulic structure as guidance, low pressure is formed at local landwaste top in the shaft bottom, expose thereby strengthen the rolling of landwaste, startup and new catalase face, improve the broken rock drilling efficiency of drill bit.

Description of drawings

Fig. 1 shaft bottom waterpower pumped down drilling tool schematic diagram

1. drill bit connects pipe nipple; 2. low pressure chamber; 3. driving nozzle; 4. ejection cavity; 5. suction tube

The specific embodiment

Now the utility model will be further described in conjunction with Figure of description.

When adopting the utility model to form local depression in the shaft bottom, drill bit connects pipe nipple [1] and axially connects, two ends are processed with screw thread, top and bottom link with drill string and drill bit respectively, connect pipe nipple [1] middle part at drill bit and be processed with low pressure chamber [2], the outlet of low pressure chamber [2] is pointed on the annular space and is returned direction, the axis of low pressure chamber [2] connects pipe nipple [1] with drill bit axis is space antarafacial relation, driving nozzle [3] is installed in an end that connects pipe nipple [1] inwall in the low pressure chamber [2] near drill bit, in driving nozzle [3] exit, drill bit connects pipe nipple [1] middle part and is processed with ejection cavity [4], the axes intersect of the axis of ejection cavity [4] and low pressure chamber [2], termination near drill bit connection pipe nipple [1] inwall in ejection cavity [4] has suction tube [5], drill bit internal is stretched in suction tube [5] lower end, the straight cutting shaft bottom, driving nozzle [3] adopts to be sealed and matched and is installed in the low pressure chamber [2].

When adopting the utility model to form local depression in the shaft bottom, because the area of passage of bit nozzle is less, when drilling fluid flows through nozzle, can produce bigger pressure drop, in drill string and between the outside annular space, form pressure reduction, drilling fluid is under the effect of this pressure reduction, quicken through driving nozzle [3], form and point to the high-speed jet of returning direction on the annular space, exit region in driving nozzle [3], because the effect of entrainmenting of jet, formed a low-pressure area, this low-pressure area acts on the local shaft bottom of suction tube [5] entrance area through ejection cavity [4] and suction tube [5], make the head of liquid on suction tube [5] the entrance area landwaste reduce, rolling of landwaste, the difficulty that startup and new catalase face expose descends, and drill bit rock-breaking and well-drilling efficient improves, and the amplitude that head of liquid reduces on the landwaste passes through to adjust the inside and outside pressure differential of drill string, the flow passage structure of driving nozzle [3], property of drilling fluid, ejection cavity [4], the parameters such as relative position of driving nozzle [3] and low pressure chamber [2] obtain.

Claims

1. shaft bottom waterpower pumped down drilling tool, it mainly connects pipe nipple by drill bit, low pressure chamber, driving nozzle, ejection cavity, formations such as suction tube, it is characterized in that drill bit connects pipe nipple [1] and axially connects, two ends are processed with screw thread, top and bottom link with drill string and drill bit respectively, connect pipe nipple [1] middle part at drill bit and be processed with low pressure chamber [2], the outlet of low pressure chamber [2] is pointed on the annular space and is returned direction, the axis of low pressure chamber [2] connects pipe nipple [1] with drill bit axis is space antarafacial relation, driving nozzle [3] is installed in an end that connects pipe nipple [1] inwall in the low pressure chamber [2] near drill bit, in driving nozzle [3] exit, drill bit connects pipe nipple [1] middle part and is processed with ejection cavity [4], the axes intersect of the axis of ejection cavity [4] and low pressure chamber [2], termination near drill bit connection pipe nipple [1] inwall in ejection cavity [4] has suction tube [5], drill bit internal is stretched into, the straight cutting shaft bottom in suction tube [5] lower end.

2. shaft bottom according to claim 1 waterpower pumped down drilling tool is characterized in that driving nozzle [3] adopts to be sealed and matched to be installed in the low pressure chamber [2].