Drilling well down-hole, a kind of deep current divider
Technical field
The utility model belongs to deep drilling engineering hole cleaning technical field, is specifically related to drilling well down-hole, a kind of deep current divider.
Background technology
In drilling engineering, drill bit creeps into and can constantly produce landwaste or other stratum foreign material, and in time the landwaste in bore hole annulus and foreign material being cleaned and carry is out the important mission of drilling fluid.Effect of hole cleaning well just can be guaranteed rate of penetration, realizes safety and creeps into.In order to guarantee effect of hole cleaning, the drilling fluid speed in annular space must be greater than certain critical flow velocity, just have on enough kinetic energy cutting carrings, returns.Yet Shallow Reservoirs is exploited totally substantially, Deep Oil-gas becomes important one of the energy of taking over, and exploitation Deep Oil-gas just must be beaten deep-well, ultradeep well.Along with the continuous increase of drilling depth, the level of sleeve pipe also constantly increases, more past depths, and the size of sleeve pipe is less, and this just makes the area of passage of bore hole annulus reduce along with the increase of the degree of depth.Even if the speed at slim-hole place has reached hole cleaning requirement, while returning in the large scale annular space of top on drilling fluid, speed drops to possibly lower than critical flow velocity, thereby occurs taking rock difficulty, stops up.So, while only having drilling fluid flow velocity in the maximum size annular space of top to be greater than critical flow velocity, just can guarantee that the annular space at each section of sleeve pipe place in whole well can meet clean-up effect.But at this moment, the drilling fluid flow velocity in foot slim-hole can be excessive, causes circulation loss excessive, reduced bit hydraulic horsepower, and taking rock drilling fluid also can wash away the borehole wall, drilling tool at a high speed in addition, cause hole diameter to expand and drilling tool failure.Therefore, improve circulation of drilling fluid in well, both met the hole cleaning requirement of each layer of well section, not causing again excessive circulation loss and washing away is deep drilling engineering urgent problem.
Summary of the invention
To be solved in the utility model is the problem existing for hole cleaning in the drilling engineering of existing deep, and a kind of dependable performance is provided, and installs simply, and can meet hole cleaning requirement simultaneously and weaken drilling well down-hole, the deep current divider washing away.
To achieve these goals, the utility model adopts following technical scheme:
Drilling well down-hole, a deep current divider, is a steel annular cylinder, and upper and lower two ends are provided with screw thread, for connecting upper and lower drilling rod.Current divider middle part, along circumferentially equidistantly offering four shunting circular holes, is provided with an one way valve in each shunting circular hole, allow the inner drilling fluid of current divider to flow to outside annular space, but it is inner not allow annular fluid to flow into current divider.After current divider jointed rod, be lowered to the joint of pit shaft supreme layer sleeve pipe and lower floor's sleeve pipe, make to shunt circular hole and align with lower floor's sleeve pipe upper surface.
The axis angle of described shunting round hole axial and current divider annular cylinder
αit is 45 °~60 °.
The utility model, owing to taking above technical scheme, has the following advantages:
1, current divider is installed at annular space change in size place, can shunt drilling fluid to annular space, make bottom slim-hole annular space flow be less than top big hole annular space flow, thereby reduce the change in flow in bore hole annulus, both met the hole cleaning requirement of each layer of well section, and do not caused again excessive circulation loss and wash away.
Accompanying drawing explanation
Fig. 1 is structural representation of the present utility model
Fig. 2 is the longitudinal section sectional view after the utility model is installed
Fig. 3 is the sectional view of the utility model shunting circular hole
Wherein: 1, current divider; 2, upper strata sleeve pipe; 3, lower floor's sleeve pipe; 4, shunting circular hole; 5, one way valve.
The specific embodiment
Below in conjunction with accompanying drawing, concrete enforcement of the present utility model is further described.
The utility model relates to drilling well down-hole, a kind of deep current divider 1, and as depicted in figs. 1 and 2, current divider 1 is a steel annular cylinder, and upper and lower two ends are provided with screw thread, for connecting upper and lower drilling rod.Current divider 1 middle part, along circumferentially equidistantly offering four shunting circular holes 4, is provided with an one way valve 5 in each shunting circular hole 4, allows the inner drilling fluid of current divider 1 to flow to outside annular space, but does not allow annular fluid to flow into current divider 1 inside.After current divider 1 jointed rod, be lowered to the joint of pit shaft supreme layer sleeve pipe 2 and lower floor's sleeve pipe 3, make to shunt circular hole 4 and align with lower floor's sleeve pipe 3 upper surfaces.
As shown in Figure 3, the axis angle of described shunting circular hole 4 axis and current divider 1 annular cylinder
αit is 45 °~60 °.
Specific embodiment:
Drilling well down-hole, a kind of deep current divider 1 is connected by screw thread with drilling rod, after connection, with drilling rod, be lowered to the joint of pit shaft supreme layer sleeve pipe 2 and lower floor's sleeve pipe 3, the shunting circular hole 4 of offering on current divider 1 is alignd with lower floor's sleeve pipe 3 upper surfaces, make the drilling fluid flowing out by shunting circular hole 4 can wash away the step position of upper strata sleeve pipe 2 and 3 linkings of lower floor's sleeve pipe, make the landwaste depositing can be recycled to ground herein.In addition, the shunting circular hole 4 of offering obliquely, can avoid the drilling fluid of eliminator 1 inside that one way valve 5 is produced directly and impacted.Rely on the pressure differential of current divider 1 inside and outside drilling fluid to open the one way valve 5 in shunting circular hole 4, make drilling fluid in drilling rod can be smoothly through shunting circular hole 4 and flow in annular space, but drilling fluid in blocking-up annular space is back in drilling rod.This just makes bottom slim-hole annular space by less flow, and top big hole passes through larger flow, thereby reduces the current difference of drilling fluid in annular space.When meeting hole cleaning requirement, do not have excessive flow velocity and exist, thereby weakened erosion.
During deep drilling well, current divider 1 is installed at annular space change in size place, can be made the well section of different annular space sizes all have more suitable mud flow rate, when meeting each layer of well section hole cleaning requirement, do not cause again excessive circulation loss and wash away.