CN104265179B - A kind of variable curvature screw pile driver drill bit - Google Patents
A kind of variable curvature screw pile driver drill bit Download PDFInfo
- Publication number
- CN104265179B CN104265179B CN201410477060.2A CN201410477060A CN104265179B CN 104265179 B CN104265179 B CN 104265179B CN 201410477060 A CN201410477060 A CN 201410477060A CN 104265179 B CN104265179 B CN 104265179B
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- curved surface
- soil
- screw blade
- drill bit
- pick
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- 239000002689 soil Substances 0.000 claims abstract description 65
- 238000005553 drilling Methods 0.000 claims abstract description 43
- 238000005520 cutting process Methods 0.000 claims abstract description 8
- 239000011159 matrix material Substances 0.000 claims description 9
- 230000002093 peripheral effect Effects 0.000 claims description 6
- 241001074085 Scophthalmus aquosus Species 0.000 abstract description 10
- 210000003371 toe Anatomy 0.000 abstract description 7
- 238000003795 desorption Methods 0.000 abstract description 3
- 238000003556 assay Methods 0.000 abstract description 2
- 238000005457 optimization Methods 0.000 abstract description 2
- 238000000034 method Methods 0.000 description 8
- 230000008569 process Effects 0.000 description 7
- 230000000694 effects Effects 0.000 description 5
- 238000005452 bending Methods 0.000 description 3
- 238000010276 construction Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 238000009412 basement excavation Methods 0.000 description 2
- 239000004927 clay Substances 0.000 description 2
- 238000005065 mining Methods 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- 230000006978 adaptation Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000010429 evolutionary process Effects 0.000 description 1
- 210000002683 foot Anatomy 0.000 description 1
- 238000002372 labelling Methods 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 239000011435 rock Substances 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B10/00—Drill bits
- E21B10/42—Rotary drag type drill bits with teeth, blades or like cutting elements, e.g. fork-type bits, fish tail bits
- E21B10/43—Rotary drag type drill bits with teeth, blades or like cutting elements, e.g. fork-type bits, fish tail bits characterised by the arrangement of teeth or other cutting elements
Landscapes
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Earth Drilling (AREA)
Abstract
A kind of variable curvature screw pile driver drill bit, including drilling rod, apex point, screw blade and brill pick, boring the two N-Side surfs respectively interior tactile soil curved surface of pick and outer tactile soil curved surface, the contour curve of the contour curve and outer tactile native curved surface that bore the interior tactile native curved surface in the rip cutting section of pick corresponds with different equations;Described apex point is formed by around bury centrosymmetric three the apex point matrixes in the center of circle of end face of drilling rod.In the present invention, used by drill bit, equation curve is based on assay optimization, it is applied to bore the inside and outside bionical curve touching soil curved surface of pick and comes from cock toes tactile soil curved surface, its toe inside and outside contour touches soil curve and has good soil drag reduction desorption ability, this structure is applied in the brill pick position of drilling bit of pile engine, not only make piling machine have and well excavate soil capacity, reduce the soil resistance suffered by drill bit simultaneously, improve service life and the work efficiency of drill bit.
Description
Technical field
The present invention relates to drilling equipment rock crushing tool field, specifically a kind of variable curvature screw pile driver drill bit.
Background technology
Screw pile driver, as a kind of common engineering machinery, has important application in the engineerings such as bridge, roadbed and tunnel.At present, drill bit conventional in engineering construction is made up of drilling rod, apex point, brill pick and spiral guide sheet etc., and screw blade is fixed on drilling rod, and apex point and brill pick are welded on boring bar head, become inseparable one with drilling rod, and drilling rod is hollow-core construction.The piling drill bit of this kind of structure there is problems in that 1, apex point and brill pick serious wear in the process of piling;2, in the process of piling, screw blade Clay Problem is serious;3, apex point force structure is unreasonable, and in actual piling process, problem above can have a strong impact on piling efficiency, extends the engineering time, meanwhile, reduces the life-span of drilling bit of pile engine.
Summary of the invention
Owing to drilling bit of pile engine Problems existing in piling process is not only relevant with drill bit material and structure, also and relevant with the bit face geometry of soil sliding contact, the invention aims to solve the problem that existing drill bit structure is unreasonable, clay is serious and the life-span is short, redesign the shape of drill bit, it is provided that a kind of variable curvature screw pile driver drill bit.
The technical scheme that the present invention adopts for achieving the above object is: a kind of variable curvature screw pile driver drill bit, including cylindrical drilling rod, be located at drilling rod bury end apex point, along the screw blade of drilling rod outer peripheral face helical disk row and be fixed on screw blade and bury two of end and bore pick, boring the two N-Side surfs respectively interior outer tactile soil curved surface touching soil curved surface and inwardly tactile soil curved surface bending of pick, the contour curve boring the interior tactile native curved surface in the rip cutting section of pick corresponds with equationWith, the span of t is 5 ~ 12;The outer contour curve touching soil curved surface corresponds with equationWith, the span of t is 5 ~ 12;
Described apex point is formed by around bury centrosymmetric three the apex point matrixes in the center of circle of end face of drilling rod, apex point matrix from apex point top center to apex point bottom outline curve meet equation:,, t span is 5 ~ 145.
In the present invention, boring and touch soil curved surface in crossing in pick side with the rip cutting section of outer tactile soil curved surface, the contour curve end of interior tactile soil curved surface connects with the contour curve end circular arc of outer tactile soil curved surface, and this arc radius is 30cm.
The side of each apex point matrix reverses 40 ° all clockwise or counterclockwise.
The screw blade of the present invention is formed by circular sliding slopes by secondary screw blade and the multi-thread principal screw blade of single line, and the screw diameter of pair screw blade and principal screw blade is 60cm, principal screw blade is identical with the structure of secondary screw blade, screw blade is gerotor type, and the outline curvilinear equation of screw blade isWith, t span is 3 ~ 147, and screw blade is by this curvilinear equation under certain screw diameter and helical pitch, and the outer peripheral face helical disk around drilling rod arranges and forms.Wherein, the pitch of principal screw blade is 30cm, and the helical pitch of secondary screw blade is 5cm, and two are bored pick with drilling rod axis for axis of symmetry, are respectively provided at the end of burying of secondary screw blade.
The drilling bit of pile engine of the present invention includes drilling rod four part boring pick, the screw blade of gerotor type, the apex point of the asymptotic line style of distortion type and cylinder of bionic-type, the working diameter of drilling bit of pile engine is 60cm, the diameter of drilling rod cross section transverse is 25cm, the setting that the active length of drill bit can carry out as required, changes relevant parameter simultaneously and mates.Above equation curve is primitive curve, can need to zoom in and out according to actual condition in actual production and processing, and the intrinsic geometry form of curve does not change.
The present invention, based on bionical and analytical geometry method, reaches to increase the service life, and improves the purpose of production efficiency.It is applied to the gerotor type curve of screw blade, screw blade shows as mild concaveconvex structure, the stress field of this special construction shows as continuous print fluctuating nature, the continued jitters of stress field cause soil adhesion cutterhead probability be substantially reduced, this kind of structure shows excellent reducing adhesion performance in soil box is tested.
Beneficial effect:
(1), in the present invention, used by drill bit, equation curve is based on assay optimization, has special geometry soil function.Wherein, it is applied to bore the inside and outside bionical curve touching soil curved surface of pick and comes from cock toes tactile soil curved surface, cock is looked for food in process daily, toe has very strong soil mining ability, and in long evolutionary process, its toe inside and outside contour touches soil curve and has good soil drag reduction desorption ability, this structure is applied in the brill pick position of drilling bit of pile engine, not only make piling machine have and well excavate soil capacity, reduce the soil resistance suffered by drill bit simultaneously, improve service life and the work efficiency of drill bit;
(2), the curvilinear equation of apex point matrix is asymptotic line style curve, excellent de-soil nature energy is shown in Soil simulation is tested, the soil of motion can be produced guiding effect and produce to roll effect to soil particle by asymptotic line style geometry monomer simultaneously, this reduces the sticking probability of soil and apex point surface, simultaneously, the side of each apex point matrix reverses 40 ° all clockwise or counterclockwise, apex point is operationally, the soil excavated can be sent into screw blade easily, and then raising excavation speed, reduce the possibility that rig adheres to, compared with prior art, show excellent desorption drag-reduction effect;
(3), drilling bit of pile engine is redesigned by the present invention, a kind of asymptotic line style curve is applied to apex point design, it is applied to one bionic-type curve bore pick design, apex point and brill curve corresponding to pick are respectively provided with special soil geometrical performance, could alter that soil is in contact with it the kinestate on surface, the soil of motion is produced smooth cutting effect, thus reducing the working resistance of piling machine;This kind of structure can also make the stress field of soil show as continuous print fluctuating nature, the continued jitters of stress field can cause soil adhesion drill bit probability be substantially reduced, drill bit is made to have stronger ability of burying and take off soil effect preferably, simultaneously, when operation, it is possible to dispersion ground pressure, reduce and touch soil area, thus reducing soil adhesion, reduce soil resistance;The present invention not only makes piling machine have good soil mining ability, reduces the excavating resistance of soil simultaneously, improves service life and the work efficiency of drill bit.
Accompanying drawing explanation
Fig. 1 is the overall structure figure of drill bit;
Fig. 2 is the top view of Fig. 1;
Fig. 3 is the apex point front view of asymptotic line style after distortion;
Fig. 4 is the contour curve figure boring pick rip cutting section;
Fig. 5 is the axonometric chart boring pick;
Fig. 6 is the partial schematic diagram of screw blade.
Accompanying drawing labelling: 1, drilling rod, 2, apex point, 201, apex point matrix, 3, bore pick, 301, interior tactile soil curved surface, 302, outer tactile soil curved surface, 4, principal screw blade, 5, secondary screw blade.
Detailed description of the invention
A kind of variable curvature screw pile driver drill bit, as it is shown in figure 1, include cylindrical drilling rod 1, be located at drilling rod 1 and bury the apex point 2 of end, along the screw blade of drilling rod 1 outer peripheral face helical disk row and be fixed on bury two of end of screw blade and bore pick 3.
Wherein, two are bored pick 3 and are symmetrical in the axis of drilling rod 1 and are symmetrical arranged, and two brill pick 3 all bend to the direction, axis of drilling rod 1, the two of which opposite flank boring pick 3 is bending curve, touches soil curved surface 301 and the inside outer tactile soil curved surface 302 touching soil curved surface 301 bending in respectively;The another two opposite flank boring pick 3 is perpendicular.The contour curve of the interior tactile soil curved surface along the section boring pick 3 perpendicular corresponds with equationWith, t span is 5 ~ 12;The outer contour curve touching soil curved surface corresponds with equationWith, t span is 5 ~ 12;Boring in the rip cutting section of pick 3 side, the contour curve end of interior tactile soil curved surface connects with the contour curve end circular arc of outer tactile soil curved surface, and this arc radius is 30cm.
Apex point 2 is formed by around bury centrosymmetric three the apex point matrixes 201 in the center of circle of end face of drilling rod, apex point matrix 201 from apex point 2 top center to apex point 2 bottom outline curve meet equation:With, t span is 5 ~ 145;The side of each apex point matrix 201 reverses 40 ° all clockwise or counterclockwise.
Wherein, as shown in Figure 1, screw blade is formed by circular sliding slopes by secondary screw blade 5 and the multi-thread principal screw blade 4 of single line, secondary screw blade 5 is identical with the screw diameter of principal screw blade 4, described two bore pick 3 with drilling rod 1 axis for axis of symmetry, are respectively provided at the end of burying of secondary screw blade 5.
Further, the outline curvilinear equation of screw blade isWith, t span is 3 ~ 147, and screw blade is by this curvilinear equation under certain screw diameter and helical pitch, and the outer peripheral face helical disk around drilling rod 1 arranges and forms.
As shown in Figure 1, drill bit includes bionic-type and bores drilling rod 1 four part of pick 3, gerotor type screw blade, distortion type asymptote apex point 2 and cylinder, the clockwise twist of apex point curve novelty on asymptotic basis 40 °, the soil that apex point operationally excavates can be sent into screw blade easily, and then raising excavation speed, reduce the possibility that rig adheres to.The working diameter of drill tip is 60cm, and namely the screw diameter of secondary screw blade 5 and principal screw blade 4 is 60cm, and the diameter of the cross section transverse of drilling rod 1 is 25cm, and the pitch of principal screw blade 4 is 30cm, and the helical pitch of secondary screw blade 5 is 5cm.Apex point 2 and drilling rod 1 are seamless welding, and screw blade and drilling rod 1 are seamless welding, and the anglec of rotation is 180 degree, and each blade all processes through fillet.Boring pick 3 and be welded on the end of burying of secondary screw blade 5, two brill pick 3 are symmetrical structure, the setting that the active length of drill bit can carry out as required, change relevant parameter simultaneously and mate.
Due to the material that biology carries out through long-term and nature, energy and information exchange, create the system adapting to ecological environment, many science and technology difficult problems have obtained at biosphere and have satisfactorily resolved, in the present invention, it is applied to bore the inside and outside bionical curve touching soil curved surface of pick and comes from cock toes tactile soil curved surface, in the cock toes active adaptation process with soil, the maximum feature formed is to excavate foot prosperity, this structure is applied in the brill pick position of drilling bit of pile engine, not only make piling machine have and well excavate soil capacity, reduce the soil resistance suffered by drill bit simultaneously, improve service life and the work efficiency of drill bit.
Above equation curve is primitive curve, can need to zoom in and out according to overall size in actual production and processing, and the intrinsic geometry form of curve does not change.The concrete size of above-mentioned geometry entity and distribution spacing also should be determined according to concrete working environment and soil property;Meanwhile, should be taken into account the height of the quality of processing technology and use cost.Machining process route should according to material behavior, and existing processing method is specifically formulated.
Claims (5)
1. a variable curvature screw pile driver drill bit, including cylindrical drilling rod (1), be located at drilling rod (1) bury end apex point (2), along the screw blade of drilling rod (1) outer peripheral face helical disk row and be fixed on screw blade and bury two of end and bore pick (3), it is characterized in that: boring two N-Side surfs respectively interior tactile soil curved surface (301) of pick (3) and inwardly touch the outer tactile native curved surface (302) that native curved surface (301) bends, the contour curve boring the interior tactile soil curved surface in the rip cutting section of pick (3) corresponds with equationWith, the span of t is 5 ~ 12;The outer contour curve touching soil curved surface corresponds with equationWith, the span of t is 5 ~ 12;
Described apex point (2) is formed by around bury centrosymmetric three the apex point matrixes (201) in the center of circle of end face of drilling rod (1), and from apex point (2) top center to apex point (2), the outline curve of bottom meets equation to apex point matrix (201):With, t span is 5 ~ 145, and the side of each apex point matrix (201) reverses 40 ° all clockwise or counterclockwise, and the outline curvilinear equation of described screw blade isWith, t span is 3 ~ 147, and screw blade is by this curvilinear equation under certain screw diameter and helical pitch, and the outer peripheral face helical disk around drilling rod (1) arranges and forms.
2. a kind of variable curvature screw pile driver drill bit according to claim 1, it is characterised in that: boring in the rip cutting section of pick (3) side, the contour curve end of interior tactile soil curved surface connects with the contour curve end circular arc of outer tactile soil curved surface, and this arc radius is 30cm.
3. a kind of variable curvature screw pile driver drill bit according to claim 1, it is characterized in that: described screw blade is formed by circular sliding slopes by secondary screw blade (5) and the multi-thread principal screw blade (4) of single line, principal screw blade (4) is identical with the screw diameter of secondary screw blade (5), described two bore pick (3) with drilling rod (1) axis for axis of symmetry, are respectively provided at the end of burying of secondary screw blade (5).
4. a kind of variable curvature screw pile driver drill bit according to claim 3, it is characterized in that: the pitch of described principal screw blade (4) is 30cm, the helical pitch of secondary screw blade (5) is 5cm, and the screw diameter of secondary screw blade (5) and principal screw blade (4) is 60cm.
5. a kind of variable curvature screw pile driver drill bit according to claim 1, it is characterised in that: the diameter of the cross section transverse of described drilling rod (1) is 25cm.
Priority Applications (1)
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CN201410477060.2A CN104265179B (en) | 2014-09-18 | 2014-09-18 | A kind of variable curvature screw pile driver drill bit |
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CN201410477060.2A CN104265179B (en) | 2014-09-18 | 2014-09-18 | A kind of variable curvature screw pile driver drill bit |
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CN104265179A CN104265179A (en) | 2015-01-07 |
CN104265179B true CN104265179B (en) | 2016-07-13 |
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CN201410477060.2A Expired - Fee Related CN104265179B (en) | 2014-09-18 | 2014-09-18 | A kind of variable curvature screw pile driver drill bit |
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Families Citing this family (2)
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CN105464589B (en) * | 2016-01-11 | 2017-11-17 | 河南理工大学 | For cherry coal rock, the bionical drilling method of resistance radiating and drilling rod drop |
CN114875910B (en) * | 2022-06-13 | 2024-02-20 | 中冶建工集团有限公司 | Pile hole treatment device of pile foundation based on foundation treatment and use method |
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2014
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