GB/T17984

03+0.

01(L/d) ; When D<2mm: Do not stipulate radial circle is jumpy value (among them D is diameter of section of twist drill job; L is) of twist drill length. The regulation that 85 standards of our country are worth to this public errand did not consider to grow diameter comparing, stipulate by the diameter radial circle is jumpy only, apparent and insufficient reasonable. Compare with 85 standards photograph, this standard asks to relax somewhat to this public errand, but have a bit to big norms broach add severe. The radial circle that this standard sets beats the diametical limits that is worth correspondence is 2 ～ 100mm. When need design produces D>100mm twist drill, technical index is decided by both sides of supply and demand or just ask to decide by oneself according to needing for root. Inclined Xiang Yuan is jumpy (point height is poor) blade of twist drill cutting is right the inclined Xiang Yuan of working section axes is jumpy the symmetry that is used at assessing cutting point. Error of cutting point symmetry is bigger, broach life is lower, and make easily be machined bore diameter is outspread, bore loss of accuracy. The inclined Xiang Yuan that this standard sets exact form twist drill is jumpy be worth standard of adopting equation international, namely D<2.

When 5mm: Dh=0.

025mm; D ≥ 2.

When 5mm: Dh=0.

013d0.

699. The inclined Xiang Yuan of average level twist drill beats the value adjusts for: D<2.

When 5mm: Dh=0.

08mm; D ≥ 2.

When 5mm: Dh=0.

056d0.

380. The inclined Xiang Yuan that this standard sets beats the diametical limits that is worth correspondence is 1 ～ 100mm, the inclined Xiang Yuan of D>100mm broach is jumpy be decided by both sides of supply and demand or by need to just ask to decide for square basis, the inclined Xiang Yuan of D<1mm twist drill beats tolerancepublic errand value is equal the regulation at 1mm twist drill. Twist drill of the symmetry that get core gets core to be opposite to the symmetry of working section axes twist drill life and bore precision have bigger effect. The experiment makes clear, the symmetry getting core of twist drill of Ø15mm awl power by 0.

05mm increases 0.

Life of the broach when 10mm will drop 16% ; Get core symmetry to increase to 0.

20 ～ 0.

Life of the broach when 30mm will drop 44% , bore is average and outspread quantity general by 0.

25mm increases 0.

40mm. Visible, symmetry of control getting core is very important to assuring broach quality. The adopting equation of the symmetry that get core that this standard sets exact form twist drill is corresponding ISO standard, namely when D ≤ 1mm: Dk=0.

08mm; When D>1mm: Dk=0.

08d0.

537. The hot-rolling craft that considers our country and mill make craft current situation, the symmetry getting core of average level twist drill consults international standard adjusts for: When D ≤ 1mm: Dk=0.

10mm; When D>1mm: Dk=0.

10d0.

489. The symmetry getting core of D>100mm twist drill is decided by both sides of supply and demand. Graduation of groove of groove graduation error (divide into equal parts of former channel weighing blade) the error is bigger to bore precision influence, 85 standards of our country set error of groove divide into equal parts to twist drill of exact form straight power only. The standard of international of adopting equation of error of groove divide into equal parts that this standard sets exact form twist drill, namely when D ≤ 1mm: Dd=0.

027mm; When D>1mm: Dd=0.

027d0.

974. The error of groove divide into equal parts of average level twist drill consults ISO standard adjusts for: When D ≤ 1mm: Dd=0.

1mm; When D>1mm: Dd=0.

1d0.

690. The groove graduation error of D>100mm twist drill is decided by both sides of supply and demand. Working section diameter pours the working section diameter that this standard sets taper to pour level of ISO10899 of taper adopting equation, it is on every 100mm length namely 0.

02 ～ 0.

08mm, but of working section diameter always pour taper not to exceed 0.

25mm. The twist drill of D<6mm of diameter of ISO10899 standard regulation allows not to make drill (but cannot have awl) . Because broach works to make awl can reduce the attrition with hole wall partly, be helpful for preventing broach to break off. Accordingly, the working part that this standard still provides D<6mm twist drill should be made have awl, its value is by 85 standards regulation: It is on every 100mm length 0.

03 ～ 0.

12mm; Drill can be not made when D<1mm, be patient of is more than 0.

Of 003mm awl, but should control inside limits of diametical public errand. The increment that get core and this standard is opposite the ply that get core the regulation of the standard of ISO10899 of requirement adopting equation of the increment that get core, allow to get direction of petiole of core face twist drill to increase, its value is decided oneself by the manufactory. 85 standards of our country have mensurable regulation to getting core increment, it is on every 100mm length namely 1.

4 ～ 2.

0mm. As new structure twist drill (if parabola chamfer form gets first class) use, mensurable to getting core increment to make regulation already no longer appropriate. This level is right the regulation of standard of ISO10899 of requirement adopting equation of the ply that get core, the ply getting core that recommends than 85 standards is a bit a few smaller. This standard checks twist drill angle the regulation of the standard of ISO10899 of requirement adopting equation of twist drill angle, namely helix angle is decided oneself by the manufactory (also can make) by agreement of both sides of supply and demand; The angle public errand of twist drill vertex angle is 3 ° of ± (85 standards do not have this requirement) . Carry out a proof: Below general requirement, the life of twist drill follows the accretion of helix angle and increase. Helix angle is bigger, criterion before part is larger, cutting is lighter, torsion and axial force are smaller, and be helpful for discharging bits. But if helix angle is too big, can weaken cutting blade intensity, make come loose hot condition is exasperate, blade of easy generation collapse, can increase the distance that discharge bits and platoon bits resistance at the same time. Accordingly, production enterprise chooses to suit to be machined according to user demand the twist drill helix angle of material is very important. If German standard recommends: H helix angle (15 ° of 10 ° ～ ) apply to treatment hard data, be like hard plastic, brass; N helix angle (36 ° of 15 ° ～ ) apply to treatment average data, wait like medium carbon steel, mild steel; W helix angle (45 ° of 38 ° ～ ) apply to treatment weak data, wait like stainless steel, soft aluminium, red copper. The standard of ISO10899 of adopting equation of public errand of straight handle diameter of twist drill of class of nicety of public errand of straight handle diameter sets; Average level twist drill is straight handle diameter public errand still follow former 85 standards, did not make specific provision. Standard of ISO10899 of adopting equation of width of first flank of first flank width sets, to first flank width the regulation has recommend a value (FG=0.

110d0.

75) , upper limit is worth (Fu=0.

158d0.

75) and floor level are worth (FL=0.

08d0.

75) , the first flank width that sets exact form twist drill at the same time must not exceed the 1/3 that gives first flank width common difference. In the limits of public errand of first flank width that the value of first flank width that 85 standards of our country recommend basically is located in ISO standard to set. To the twist drill of D>100mm, first flank width can be decided by both sides of supply and demand; To the twist drill of D<1mm, first flank width can consult afore-mentioned formulary computation. Additional, this standard sets D ≤ 0.

The twist drill of 75mm can not make first flank. This standard regulation twist drill uses the data of twist drill the other shop sign of W6Mo5Cr4V2 or coequal function is common high-speed steel (HSS) is made, handle via exterior aggrandizement. The other name that also can use W2Mo9Cr4VCo8 or coequal property is high-powered high-speed steel (HSS-E) is made. The experiment proves: The twist drill that handles via exterior aggrandizement (include mill to make, rolling, rub is made, crowded make, grind make bit) life but twice rises. The hardness of standard of our country of hardness of section of job of heat treatment hardness asks to use Rockwell hardness for a long time, but the methodological talent that uses surface grinding only to the twist drill of D<3mm detects Rockwell hardness. Regulation of ISO10899 mark criterion uses diamond pyramid hardness, twist drill can be not destroyed to be able to detect again already when detecting the twist drill hardness of D<3mm, because this is more reasonable. This standard adopting equation ISO10899 standard regulation. Detect when diamond pyramid hardness, taller to requirement of sample surface surface roughness, different specifications twist drill is added measure load to also differ. The lower limit that 85 standards of our country set working section hardness only is worth (not under 63HRC) , and from life test of many twist drill knowable, as long as temper is sufficient, carbide is even, a lot of hardness are close to or exceed upper limit to be worth slightly (the twist drill of 66HRC) all can acquire life of more expensive work. The petiole that this standard sets petiole and flat end hardness and standard of ISO10899 of adopting equation of flat end hardness. 85 standards of our country did not make a provision to petiole hardness, set flat end hardness only (straight handle 30 ～ 45HRC, awl handle not under 25HRC) . Standard of ISO10899 of good range of temper by dipping in water did not set good range of temper by dipping in water. 85 standards of our country set good range of temper by dipping in water, make clear via producing test and verify reasonable and feasible, because this standard still set good range of temper by dipping in water; Consider at the same time use new heat treatment technology, because this permits temper by dipping in water of twist drill whole hard. The exterior quality of exterior product affects the market competition ability of the product directly. This standard retained the provision that 85 standards of our country make to twist drill exterior. Coarse experiment makes clear the surface, be opposite with the exterior surface roughness of groove at the back of twist drill cutting function has bigger effect. ISO10899 standard gave out to the first flank of twist drill and petiole regulation of exterior surface roughness; 85 standards of our country, Japan standard and former Russia level are right there all is exterior surface roughness to set with groove at the back of twist drill. Accordingly, this level is right first flank and standard of ISO of adopting equation of petiole surface surface roughness, right from the back the provision that retained 85 standards with groove surface surface roughness. Indicate and pack this standard to indicate to the product the regulation of standard of adopting equation ISO10899, this is helpful for product of our country twist drill participating in international competition and strengthen domestic and international technology to communicate. To distinguish exact form twist drill and average level twist drill, increased sign of twist drill grade, mark of exact form twist drill is " H " , average level twist drill does not make a mark, stipulate D<4mm twist drill can not make a mark. Measurement technique this standard will still measurement technique of public errand of twist drill position includes a standard the appendix. Radial circle detects jumpily the method still measures by 85 standards regulation at 2 o'clock: The a bitth be in in twist drill corner, went up in the first flank that is apart from lead of corner 1/4 groove at 2 o'clock. Of the symmetry that get core detect standard of ISO10899 of methodological adopting equation. Groove graduation error stipulates by ISO10899 the method detects, the poor 1/2 instead that takes dial gauge reading by what 85 standards set takes the difference of dial gauge reading. 5 standards executive problem and GB/T17984-2000 of strategy of mark of be linked together " condition of twist drill technology " carry out carry out the result that will obtain face of the following tripartite: ① promotes industry technology progress. A lot of design with twist drill, make, use relevant technical issue to will be in process of bid of be linked together through discussing, communication and improve get clarifying with solve. ② promotes enterprise technical reformation, quicken those who produce equipment, labour to place measure to change, raise the design of twist drill and craft level further. ③ promotes an enterprise to produce those who taste quality to rise. The improvement of standard of the craft after mark of be linked together will raise the production level of twist drill and treatment precision, improve the production quality of the product thereby. The existing standard that produces from our country twist drill is analysed, carry out this standard to will increase the production difficulty of twist drill undoubtedly, the craft of twist drill manufactory, examine, the branch such as metric, tool, equipment will be faced with a part to produce equipment, metrological implement and manufacturing environment update or upgrade problem, this may bring issue of the following sides: ① business investment is increased; ② produces cost to increase; ③ technology lays in inadequacy; ④ produces local suffocate suffocate. If this standard asks exact form does not have public errand of diameter of section of job of twist drill of awl straight power to be H8, petiole diameter public errand is H11; Have public errand of diameter of section of job of twist drill of awl nicety class to be H8, petiole diameter public errand is F11; Stipulate petiole clip holds partial cylinder to spend tolerancepublic errand for 0.

02mm. As a result of same the blade department that supports twist drill and belt of petiole public errand are different, stipulated cylinder spends tolerancepublic errand again, because this needs to change workmanship, detect the method also must be adjusted newer, influence of this certainly will machines efficiency, the equipment that adds a company is thrown and produce cost. The device of birth of major twist drill that our country uses at present still is 20 centuries the equipment of 80 time of 70 ～ , the treatment function of these equipment and technical condition and the requirement presence that implement this standard are constant difference. If the hardness of major company detects,equipment uses Rockwell hardness more, the device that uses diamond pyramid hardness is less, the enterprise detects the personnel changeover to Rockwell hardness and diamond pyramid hardness and detect methodological experience is scant, existence technology quality and technology lay in insufficient problem. Raised requirement of error of groove divide into equal parts to common twist drill like this standard again, this will increase use rolling, twist make, mill is made, extruding, rub makes the difficulty that waits for technique to produce twist drill. At present the rolling precision of rolling mill of domestic major twist drill cannot get used to this standard requirement; Mill makes first class of the milling machine of twist drill, tool, graduation also need to raise precision. Of equipment, tool transform newlier have a process, manufacturing requirement is satisfied very hard inside short time, consequently the likelihood causes local production suffocate suffocate, this is one of difficulty of mark of be linked together. To solve afore-mentioned problems, the author thinks, in process of bid of be linked together, want to promote industry technology progress already, want to assure the normal production of the enterprise again; Want to improve product quality already, want to consider the actual ability of the enterprise again. Accordingly, use minute of pace to carry out, the strategy of mark of be linked together that reachs the designated position stage by stage is relatively beautiful choice, namely the first pace is transfer level, the 2nd pace is overall executive level. In transfer level, answer to be a basis with technical analysis, in a planned way, undertake by importance capital is thrown; To updating equipment, answer to solve the common metrological implement that manufacturing site is badly in need of above all, as far as possible continue to use or change make existing tool, designedly carries out equipment to transform or introduce, raise equipment to ensure a level; To producing difficulty commonly, should create a condition to be solved as far as possible; To special production difficult point, appropriate is produced normally with be not being affected and do not cause manufacturing halt to be a principle, maintain active craft position temporarily, after waiting for condition of overall executive level to mature, solve all right again; The technology that should reinforce sign of pair of be linked together considers to reach practice, raise existing technology level and equipment level stage by stage. In overall executive level, should be in transfer on the foundation of level, make cogent and effective plan, one by one solves existence problem, mark of overall follow in a continuous line implements this standard, achieve the goal that conforms with international standard. Advanced level of product of twist drill of high-speed steel of 6 epilogue our country and abroad still exists bigger difference, main body lags behind in production equipment now, the technology replaces rate slow; Blade of the horn after twist drill grinds quality difference, lack thorough research to broach cut form and main geometry parameter; Offerring optimal broach structure for the user parameter and optimal auger cut the respect such as demand of contented and dosage, different use class to still need to do a large number of works. GB/T17984 " condition of twist drill technology " the child that the standard is union of achievement of modern science and technology and photograph of manufacturing practice experience, it is in give attention to two or morethings on each foundation of square interest, study via relapsing, talk things over, test and verify and make, have but repeatability and manufacturing applicability, carry out this standard actively, reliably to produce technical level to will have tremendous stimulative effect to raising our country twist drill in the round. In the meantime, this standard conforms to product of our country twist drill and international standard, the direct effect with participate in international market competition to have main. CNC Milling CNC Machining