Get into " skid layer " broach design and use
- source:TECHEN CNC Machining
8 meters / second, the diamond of face of lip of broach of hot pressing agglomeration that causes carcass wear-resisting does not give blade and not footage, similar the terrane of this kind of circumstance should not is called " skid layer " . Normal > is alleged " skid layer " should be to exclude all sorts of operation factors, use normal pregnant to set bit, normal parameter is gotten then the terrane with very low rate of penetration. The common characteristic of this kind of terrane is: Compositive petrosal is mineral harder, mineral grain fine, structure is compact, wait like cliff of quartzite, hard granite, firestone. Its are main cliff sex index is: Press hardness 4500MPa above, compressive strength is more than odd axis 150MPa, abrasiveness under 15mg. Normal > 2, " skid layer " the design principle Normal > " skid layer " the characteristic is rock particularly hard, the structure is compact, intensity is high, abrasiveness is weak. Get into the effect according to what ability of parameter of reasonable design broach has obtained these characteristics. Its are basic the principle is: Normal >1, choose high grade making synthetic diamond. Normal > high grade has brilliant look, odd bead compressive strength is high, thermal stability is good wait for a characteristic, get into hard rock to have particularly clear advantage, low grade diamond can not is likened to. Normal >2, granuality in choosing. Normal > grows with respect to diamond and current synthetic technology level, increase as what odd grain spends, content of form of the wrap up inside crystal increases, because crystal lattice distortion brings about single crystal irregular growth trend increases, this means full size range in in waiting with 50/60, 60/70, 70/80, 80/100, wait slant form of brilliant of single crystal of fine granuality diamond lowest of the most complete, matter content, that is to say, in the single crystal of identical grade, this one granuality is had than thick granuality (the on unit area compressive strength with 35/35, 40/45, better 45/50) (than pressing) and fight impact strength index, this is OK from the 45/50 that is MBD12 grade together and 50/60 the compressive strength of two granuality (Kgf) / mesh area (Um) the difference of ratio gets a proof: Normal >45/50 granuality (Kgf) / mesh area (Um) ratio is 16/390=0.
041 Normal >50/60 granuality (Kgf) / mesh area (Um) ratio is 14/275=0.
051 Normal > is former far be less than latter. In the broken cliff job below coequal condition, have more admirable mediumer than what press slant single crystal of fine granuality diamond is had better sharp spend and durability, and thick granuality diamond because the intensity index on unit area is low, cause diamond edges and corners to be ground easily blunt and cannot threshing in time again, new cutting blade cannot give dew in time, happen thereby " skid " phenomenon. Normal > of course, because give blade inadequacy to cause broach to skid,meticulous diamond granuality is met likewise, what kind of granuality can satisfy the requirement that gets normally, can get into the relation between craft parameter to give through imitate broach evaluate and calculate roughly. Normal > broach get into behavior to be able to describe with following means: Broach is gotten into in the some diamond cutting blade on its lip face is working with the form of corkscrewed yarn, produce minute of displacement and component on two direction at the same time namely: It is Y of edge bore axial firstly, it is secondly as perpendicular as axial tangential X, of both added up to displacement and join forces Z to behave the working condition with this actual cutting blade. If tick off,this condition can spread out by geometrical model, , bowstring concerns, exist as follows relation: Normal > X2+Y2=Z2normal > takes the place of to undertake derivation into relevant data with this relation, can be evaluated and cursory consideration broach is certain those who design parameter is reasonable, if choose diamond granuality, chroma, intensity to wait, it is with determining size below exemple undertake derivation. Normal > designs 75 diamond of one φ to take core bit suppose, it is normal to press get into craft to be: 150Kgf/cm2 of 3-5 M/h of speed of 300-500r/min of broach rotate speed, footage, bit pressure, the some diamond cutting blade that is in with the biggest external diameter is calculated for the object its unit time is immanent X, Y, Z3 the displacement S on direction, set V2=4000mm/h of speed of V1=300r/min of rotate speed of time T=1min, broach, footage, criterion X, Y, Z3 the displacement S on direction is respectively: Normal TEXT-INDENT of × of 75pt">SX=75 × π : 21.
75pt">SY=4000 ÷ 60=66.
667mm Normal >SZ= √ 66.
8mm Normal > diamond cutting blade is a variety of means such as grinding, cutting, plough, crunch to petrosal treatment the result of integrated action, and actual be a kind group of blade job status, accurate computation firstly second cutting difficult job parameter is difficulty, accordingly here only with Utopian condition, namely position of Chan Ren, cutting will quantify relevant data in an attempt to to get verdict. According to afore-mentioned data, get bit every turn footage deepness is: Normal >S=SY/V1=66.
133mm Normal > can think, right now odd diamond cutting blade cuts rock deepness most greatly 0.
133mm. Normal > experience thinks, the in carcass bag of diamond single crystal sets deepness to achieve 60% when, can guarantee against is unusual fall off, the 50% in serving as cutting height holding bit of height giving blade are appropriate, because cut deep design of this diamond cutting blade,can be this diamond 20% of bead diameter. Press this train of thought, era enters afore-mentioned data that cut rock deepness, criterion diameter of grain of this diamond single crystal is: Normal >D=0.
133 × 4=0.
532mm Normal > this data is equivalent to 45/50 granuality Normal >3, choose mix granuality pregnant to set. Normal > is raise sex of broach wide chart, adopt distinct size to mix setting is an efficient way. So right " skid layer " auger enter and be not skidding the layer is gotten is possible, because terrane alternates,eliminated go up often get the appearance that changes bit. Normal >4, choose content of diamond of inferior pH indicator. Normal > decreases relatively as a result of grain of chroma small diamond, distributing to be able to increase in the bit pressure of every diamond on labial face, be helpful for diamond cutting rock, increase rate of penetration thereby. Normal >5, choose diamond logical distributinging way. Normal > adopts diamond logical distributinging way reachs broach lip range balanced wear away, can add broach service life. Normal >6, choose medium hardness carcass. Normal > before because diamond grade is not high, get into so that,often use soft carcass a dew at diamond, this is correct undoubtedly, but as a result of grade of making synthetic diamond rise ceaselessly, using high grade diamond to continue to use soft carcass, certainly will causes the premature threshing of diamond, go against footage already, have create waste, consequently, match a principle according to carcass hardness and photograph of use diamond grade, should choose medium hardness carcass to match high grade diamond drilling to skid terrane. Normal >7, choose the labial face figure with free more face. Normal > is gotten into terrane to skid thoroughly when the layer, if the labial face figure of more free face is ladder flute profile, toothed model, pointed flute profile will be helpful for rock broken, diamond is right now broken rock kind will by simple plough, press, the surface such as crunch, scrape is broken formal change is more efficient burst apart wait for bulk broken form, be helpful for rising auger fast. In the meantime, considering get fast constant problem, figure of face of requirement broach lip changes along with time elapse as far as possible small, figure of face of lip of ladder flute profile is relatively good choice. Normal >8, use diamond single crystal to keep track. Normal > skids a rock is particularly hard, use acicular alloy or get together brilliant protects diameter to often can affect footage badly, and diamond single crystal has scrape effect to hard wall of a well, be helpful for rising auger fast. Normal >9, choose sector water mouth. Normal > sector water asks for heart broach to be weighed particularly to the rope should, sector water mouth and straight water mouth are comparative, can make face of lip of broach inside and outside balanced wear away. Water mouth amount is satisfying a pink, cooling condition to fall, water mouth amount is unfavorable and overmuch. Normal >10, broach undertakes blade is handled granting to go out. Normal > grants to handle to be being gotten into " skid layer " particularly important, make broach leaves a well not classics " grind first " OK and direct footage, decreased time is rubbed first, rose to get fast. Normal > 3, " skid layer " the Normal >1, as a result of " skid layer " cliff sex is particularly hard, the bit pressure in be being gotten is crucial parameter, did not compare enoughly pressure, the pointed blade of diamond cannot press rock, below high rotate speed, diamond cutting blade is lost by polishing very quickly get into ability. Normal TEXT-INDENT of · of P=F of 48pt"> bit pressure: 48pt"> among them: F is Cm2 of area of cricoid lip area, normal >p is worth N/cm2 for unit pressure. Skid the layer asks to get pressure ratio to be gotten into other rock to want big, use commonly 882.
7N/cm2 left and right sides. Normal >2, " skid layer " broach revolution shoulds not be too fast. Too fast rotate speed will affect the refrigeration of blade of pair of cutting of face of diamond bit lip, and in " skid layer " the diamond in be being gotten gives blade general and inferior, this kind of effect will be more apparent, bring about cutting blade easily wear away ahead of schedule, grind pure appear polish giving blade, produce what the person is to skid phenomenon, control of general linear velocity is in 1.
Between 5~2m/s. Normal >3, pump wants small. Get into " skid layer " because drilling rate is inferior, the cliff noodles or vermicelli made from bean or sweet potato starch that the bottom of a well produces is relatively little also. Pump quantity slants the general makes the cliff pink amount of the bottom of a well decreases further, give dew to diamond very adverse, easy happening skid phenomenon. And pump quantity causes pump pressure greatly too taller, can quits one part bit pressure, of bit pressure reduce also can happen skid phenomenon. Normal > computation pump measures is formulary: Q=K · D Normal > type: Q - pump measures L/min Normal >D - broach, Normal >K - coefficient (general choice 4~6) Normal >4, as a result of " skid layer " rock is particularly hard, clearance of general wall of a well is lesser, choosing reaming consequently implement when should notice broach external diameter and reaming implement the dimension of external diameter cooperates, reaming implement external diameter compares broach external diameter commonly big 0.
3mm is advisable, should not exceed 0.
4mm, can affect footage otherwise. Normal >5, get into " skid layer " when, reaming implement phyletic choice, should choose reaming of diamond single crystal implement (had better be eletroplate) , should not choose get together brilliant reaming implement, its reason keeps diameter data with broach same. Normal >6, getting into " skid layer " in cannot use drilling tool of bent drill pipe, the coaxial of broach is spent should accord with design requirement, assure stability of drilling tool revolving, in case broach diamond is unusual the happening of threshing phenomenon. Its are specific index is: Drill pipe bends every meters must not exceed 1mm, drilling tool bends every meters must not exceed 0.
75mm, broach coaxial spends deviation to cannot be more than 0.
2mm. Normal >7, bit that did not have granting to give blade, should throw inside Xiang Jing a few quartz is arenaceous (granuality 0.
5~1mm) small pump amount is used after the well below broach, light bit weight, slow revolution is gotten into 5~10 change after minute get into with normal parameter. Normal >8, in be being gotten, appear " skid " when the phenomenon, when common double-barreled is gotten, should go up instantly auger, undertake to broach blade is handled going out. When the rope takes a heart to be gotten, can reduce pump quantity to increase amount of pink of hole bottom cliff, parameter returns to normal to be gotten into after making diamond give blade afresh. This kind of operation method, requirement handlers must have experience, otherwise easy cause burn auger. Normal > 4, sum up Normal > comes true " skid layer " of terrane get into normally should mix from the design of broach the use of broach two respects undertake fumble and be carryinged out, the article gave out only a few train of thought that solve a problem and direction, be drawn lessons from for the person of the same trade inside course of study and consult, discuss with the colleague. CNC Milling CNC Machining