Treatment of casing aperture department and commonly used tooling (go up)

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One, the combination of the aperture that department of aperture of casing spare parts machines a series of mutual positions on casing to precision asks, calling hole is. Aperture department can be divided fasten for parallel aperture, if graph 8-35a place is shown, coaxial aperture is, if pursue,alternate aperture is, if pursue,8-35c place is shown. Aperture fastens treatment not only the precision demand of aperture itself is higher, and the demand of pitch precision and mutual position precision is high also, because this is the key of casing treatment. What the treatment method that aperture fastens differs according to casing batch and aperture department precision asks is different and different, give respectively now discuss. (one) the main technique requirement that the treatment parallel hole that parallel aperture ties fastens is each parallel aperture center central line and datum plane are reached between the line the space size precision between and mutual position precision. Manufacturing middling uses the following kinds of methods. 1.

Looking for execute to look for execute is to be on general purpose machine tool, the treatment method of the proper place that have the aid of assists a tool to search to wanting to machine aperture. Efficiency of treatment of this kind of method is low, apply to sheet only commonly pre production. What the basis seeks square way is different. Look for execute to be able to divide again it is the following kinds: (L) is underlined before looking for execute to machine, lay off goes up in semifinished product according to part drawing the positional contour line of each aperture, press next underline undertake machining one by one. Underline and search time is longer, productivity is low, and the pitch precision that treatment comes out is low also, be in commonly ± 0.

5mm left and right sides. Underline to rise search precision, often be united in wedlock try cut a law to undertake. Press first namely underline search boring gives one opening, move main shaft to center of the 2nd aperture by the line again, try boring to give to want small hole than the design, if do not accord with a design to ask, update the position that adjusts main shaft according to measuring an outcome, reentry tries boring all right, measure, adjust, relapse a few times so, till reach the pitch size of the requirement. Although this law is taller than pressing a line purely to look for the pitch precision that getting, but pitch precision is inferior still, and the difficulty of the operation is greater, manufacturing efficiency is low, apply to sheet pre production. (2) arbor and slip gauge look for execute boring the first Kong Shi inserts arbor main shaft aperture inside (or use boring machine main shaft directly) , the slip gauge that locates according to Konghe fiducial distance constitutes certain measure next comes position of corrective main shaft, be like graph 8-36. Corrective when the feet that use stuff determines the clearance between slip gauge and arbor, slip gauge and arbor are contacted directly and injure slip gauge in order to avoid. Boring the 2nd Kong Shi, part to insert arbor in machine tool main shaft and treatment aperture, use same method to come the position of line of corrective main shaft, the precision that is apart from in order to assure Kong Xin. This kind of Kong Xin that looks for execute is apart from precision to be able to amount to ± 0.

3mm. (3) example looks for execute to make model with the board with large 10~20mm, outfit in perpendicular go up at the end panel of each aperture (or originally to go up on machine tool workbench) , be like graph 8-37. The pitch precision on example relatively the pitch precision that casing aperture fastens is tall (it is ± commonly 0.

1mm~ ± 0.

3mm) , the aperture on example relatively workpiece aperture is big, in order to facilitate boring lever is passed. Demand of precision of dimension of the aperture on example is not high, but should have taller appearance precision and fine exterior surface roughness. After example installs workpiece well and truly to go up, in machine tool main shaft jacket is expressed 1000 minutes, search by example machine tool main shaft, search hind, change boring cutter treatment namely. This law machines aperture department to give error not easily, search to going to the lavatory, pitch precision can amount to ± 0.

05mm. Cost of this kind of example is low, it is the 1/7~1/9 of boring model cost only, odd a batches small large casing treatment is commonly used this law. (4) centering is covered if graph 8-38 place is shown,look for execute, underline on preexistence workpiece, attack bolt aperture by the line again, next the centering of mount appearance precision is tall and smooth buy is covered, centering is covered with there is larger space between bolt, the 1/3~1/5 that is apart from tolerancepublic errand by the Kong Xin that the design asks next adjusts the position that all centering covers, screw bolt. The machine tool can go up after checking, cover by centering search position of boring machine main shaft, debus centering is covered, boring gives one opening. Every machine an aperture to search, till aperture fastens treatment,end. This law tool is simple, can repeat use, particularly appropriate at sheet the aperture that jig board machines to go up below the large casing below production and condition of devoid coordinate boring machine is. 2.

Standard of standard of boring of boring standard standard uses boring model clamping apparatus to machine aperture department namely. When boring hole, workpiece outfit is placed on boring model, boring lever is by bearing in the guide-post bushing of boring model, increased systematic tigidity. Such, the aperture that boring cutter passes pattern plate to go up machines the corresponding aperture on workpiece come out, machine tool precision machines precision to aperture department the impact is very little, pitch precision basically depends on the production precision of boring model, can giving the opening with taller precision in the treatment on the machine tool with inferior precision consequently is. Should use two or when the bearing of two above will guide boring lever, boring lever and machine tool main shaft must drift connection. Stiffness of lever of the boring when boring standard standard machines aperture to fasten rises greatly, fixed position clamp is rapid, saved adjust, search auxiliary time, manufacturing efficiency is tall, it is medium batch of production, large quantities of mass-produced in the treatment method that uses extensively. But the production error that exists as a result of boring model oneself, exist between guide-post bushing and boring lever clearance and wear away, so the precision of pitch can amount to ± commonly 0.

05 Mm, coaxial is spent and parallelism can be amounted to from one aspect of the matter is machined 0.


03mm; Can amount to when parting to be machined from two end 0.


05mm. In addition, the production demand of boring model is tall, periodic long, cost is high, use boring model method lesser to large casing. Using boring standard standard to machine aperture is, can machine on general purpose machine tool already, also can machine on special machine tool or modular machine tool. Graph 8-39 is the sketch map that aperture department machines with boring model on group stage machine tool. Standard of standard of graph 8-39 boring. 3.

Law of coordinate law coordinate bores hole is to be on the equipment such as common horizontal boring machine, coordinate boring machine or milling machine of numerical control boring, have the aid of at measurement unit, the relative position with perpendicular direction is made the same score in water between main shaft of tone whole machine tool and workpiece, one kind when will assure pitch precision bores hole method. On the blueprint appearance of casing, because there is gear clench the teeth to concern between Kong Yukong, have firm tolerancepublic errand demand to pitch dimension, before using coordinate law to bore hole, must reach each pitch dimension and relation of geometry of triangle of tolerancepublic errand have the aid of the mutual and perpendicular coordinate measure that regular conversion becomes technology measure catenary to be origin with center of main shaft aperture and public errand. At present a lot of factories wove coordinate of transmission shaft of main shaft box is calculated program, use personal computer to be able to complete this work very quickly. If graph 8-40a place shows the coordinate measure for 2 axes aperture,reach sketch map of tolerancepublic errand calculative. Two aperture center is apart from LOB= , YOB=54mm. When treatment, bore hole first after O, adjust visibility to move in X direction XOB, in YOB of Y direction shift, rework aperture B. This shows center is apart from LOB is assured secondhand by XOB and YOB. The common difference that analytic XOB and YOB emphasize below allocates computation. Attention, should be apart from the center in computational process deviation of semmetry of tolerancepublic errand melt into, namely LOB= = 166.

75 ± 0.

05mm. α = 18? 43 ″ of 53 ′ = of α of Cos of · of XOB = LOB 157.

764mm   is in when defining common difference of two coordinate dimension, the solution that should use planar dimension chain calculates a method. Introduce a kind of simple calculation method now. If graph 8-40b place shows: When to going up type takes complete differential and replacing each differential with increment,   of YOB of △ of XOB+2 YOB of △ of LOB = 2 XOB of △ of 2LOB of attainable following relation is used wait for tolerancepublic errand law and replace increment with tolerancepublic errand value, ε of = of YOB of △ of = of even △ XOB, criterion   of   of   of   of   of   of   of       (8-1) the type on   is graph 8-40b place show calculative of dimension catenary public errand general pattern. Take the place of this exemple data, can get ε = 0.

041mmXOB = 154.

764 ± 0.

54 ± of 041mmYOB = 0.

041mm   calculates by above knowable: After machining aperture O, should adjust a machine tool to move in X direction only XOB = 154.

764 ± 0.

041mm, move in Y direction 54 ± of YOB = 0.

041mm, rework aperture B, can make sure two aperture center is apart from LOB= secondhand. In casing kind the case that there still is the mutual position demand that keeps certain between 3 axes on the spare parts. If graph 8-42 place is shown, among them LOA= , LAB= , LOB= , YOB=54mm. When treatment, boring is over after aperture O, tone whole machine tool moves in X direction XOA, in YOA of Y direction shift, rework aperture A; Adjust a machine tool with same method next, rework aperture B. The center of A of this shows aperture and aperture B is apart from is assured secondhand by two treatment. Answer to decide two groups of coordinate first in machining a process, namely (XOA, YOA) and (XOB, YOB) reach its public errand. Learn computation to be able to get through number by graph 8-41: XOA = 50.

918, YOA = 119.

298 Mm; XOB = 157.

76, YOB = 54 Mm. When affirmatory coordinate public errand, go to the lavatory for computation, dissoluble for a few simple dimension catenary studies, if pursue,8-42 place is shown. Beg the common difference that gives to satisfy a center to be apart from LAB public errand affirmatory XAB, YAB by graph 8-43a above all. Get by type 8-1: = of XAB = XOB - XOA 106.

846 ± 0.

036mm, = of YAB = YOB - YOA 65.

298 ± 0.

036mm; But XAB, YAB gets assuring secondhand, by graph 8-42b, C two dimension catenary is used wait for tolerancepublic errand law, the coordinate measure that can seek A giving opening, B and public errand are as follows: XOA = 50.

918 ± 0.

018mm, YOA = 129.

298 ± 0.

018mm; 54 ± of XOB = 0.

018mm, YOB = 157.

76 ± 0.

018mm. The pitch precision when be being fastened to assure to machine aperture by coordinate law, in the choice primitive aperture and consideration bore hole when order, the treatment that wants a two opening that have pitch precision demand is together by the side of the ground closely orderly, accumulate the error influence to pitch precision in order to reduce coordinate size; Because of,should avoid as far as possible at the same time of main shaft box and workbench for many times shuttlecock and the effect that causes pair of fixed position precision by clearance. In addition, the primitive aperture of the choice is due taller treatment precision and fine exterior surface roughness, boring machine main shaft examines in order to assure treatment in the process relative to the accuracy at coordinate origin position. The pitch precision that coordinate law bores hole depends on the mobile precision of coordinate, it is the precision of coordinate measurement unit actually. The main form of coordinate measurement unit has: (Feet of 1) common reticle and vernier add magnifier measurement unit, its position precision is ± 0.

1~ ± 0.

3mm. (2) dial gauge and slip gauge measurement unit. Measure with common reticle feet commonly cooperate to use, adjust main shaft in average boring machine with dial gauge and slip gauge perpendicular with horizontal position, dial gauge outfit is worn in boring machine head and on transverse workbench. Positional precision can amount to ± 0.

02~ ± 0.

04mm. This kind of device adjusts take time, efficiency is low. (Feet of 3) economy scale and optical reading head measurement unit, this is a kind of uses at most measurement unit. This unit operation is convenient, precision is taller, random of economic scale feet 2 delimit space error does not exceed 5 μ M, the reading precision of optical reading head is 0.

01mm. (Display unit of 4) grating number and measurement unit of feeling La synchronized. Its reading precision is tall, for 0.


01mm. (2) the treatment that coaxial aperture fastens is produced group by group in, use boring model to machine aperture department commonly, its coaxial is spent assure by boring model. Odd a pre production, its coaxial spends below in order to a few kinds of methods to assure. 1.

Use already machined aperture to make bearing if pursue,direct 8-43 place is shown after mural Kong Jia has been versed in before casing, direct in the outfit inside aperture set, bearing and the aperture that guide boring lever to machine rear wall to go up, in order to make sure the coaxial of two aperture spends a requirement. This law is comfortable at machining the aperture with box closer wall. 2.

Those who use boring machine rear column to go up is oriented cover bearing boring staff its boring lever is this kind of method two upright bearing, tigidity is good, but this law adjusts a trouble, boring staff should grow, very cumbersome, reason is only comfortable the treatment at large casing. 3.

Use tune boring to become when bore with a reamer of apart of casing box wall is far, can use tune boring, if pursue,8-44 place is shown. Workpiece holds clip in, after aperture of boring good one end, 180o of circumgyrate of boring machine workbench, adjust workbench position, make already machined aperture and coaxial of boring machine main shaft, next rework aperture. There should be one on casing longer bore hole with place when axes has the plane that parallelism asks, before boring hole, should use first install the dial gauge on boring lever to undertake to this plane corrective, make its and boring lever axes parallel. Be like graph 8-44a, corrective hind treatment aperture A, after Kong Jia is versed in, again workbench circumgyrate 180o. , use hold the dial gauge edge on boring lever this plane is new and corrective, be like graph 8-44b, next rework B aperture, can make sure aperture of A, B is coaxial. If the long technology tool reference plane that has machined is not had on casing, on workbench of park of iron of usable also smooth president, make be secured after its surface and the aperture axes parallel that want treatment. Adjust a method Alexandrine, also can achieve the goal of two aperture coaxial. (3) the verticality error that the main technique requirement that the treatment across hole that alternate aperture ties fastens is control concerned aperture. Basically rely on the 90o on machine tool workbench to aim device on average boring machine. Because it is link stopper device, the structure is simple, but alignment precision is low. Aim device when 90o of workbench of some boring machine when precision is very low, usable heart club and dial gauge search to raising precision of its fixed position, insert heart club in machining good aperture namely, workbench dislocation 90o, shake workbench searchs with dial gauge, if pursue,8-45 place is shown. CNC Milling CNC Machining