1. bushings parts
such parts are generally shaft, bushings and other parts, expressed the view, just draw a basic view, with appropriate cross-section diagram and dimension, you can put its main shape characteristics of the local structure of expression. In order to facilitate processing at the pictures and generally based on the horizontal axis of the projection, the best choice for the position of the axis perpendicular to the side.
in the label sleeve the size of parts, often with its axis as the radial size benchmark. Note the result shown in the figure Ф14, Ф11 (penetrate section AA) and so on. This put the design requirements and processing technology base (shaft parts in the lathe, the both ends of the thimble to withstand the center axis hole) uniform anew. The length of the base are often used in important end, the contact surface (the elbow) or the processing of noodles. surface roughness shown in the figure on the right axis for the Ra6.3 shoulder, was selected as the main dimensions length basis, which note the size of 13,28,1.5 and 26.5, etc.; then right axis side for the length of the auxiliary base, which mark out the length of the shaft 96.
2. tray cover parts
basic shape of these parts is smooth rolls, generally cover, valve cover, gear and other parts, they generally have the main structure rotating body, usually the shape of the flange with a variety of both hole and rib napkin and other local structures. In the view of choice, usually selected through the symmetry plane or axis of rotation resolve sectional view view,
Christian Louboutin, meantime others need to boost the appropriate view (left hand side view, right view or top view) the part of the uniform shape and structure of expression. Shown in the figure has additional by a left view, to express with a rounded square flange and 4 holes were cloth.
in the label cover into parts of size, usually chosen as the axis via the shaft hole radial size reference, the length direction of the main dimensions important benchmark often used in face.
3. fork parts
such parts are generally fork, joining rod, bearings and other parts. Changing the position of their processing, the choice of the main view, the cardinal attentions to the position and fashion specifics. The choice of the other views,
Christian Louboutin Sale, often require 2 or extra basic outlook, and too with the applicable regional view, the cross partition diagrams expressions to express part of the local building. Block Parts drive shown in intend view, choose the statement of concise, remove wording of bearings and because the width of ribs, the right view namely no necessary, and because the T-shaped ribs, the use of more applicable section.
marked fork in the size of parts, it is usually used to install the base surface or part of the symmetry plane as a size reference. Figure dimension method.
4. box parts
In general, the shape of these parts, structural complexity than the previous 3 parts, and the processing of position alterations more. Such components generally have body, pump, gear carton and other parts. In the choice of the main view, the main considerations to the position and shape characteristics. Selection of other views should be based on the actual location of the silhouette, as appropriate, cross section, partly view, and indirect,
Christian Louboutin Flats, and other auxiliary views, to articulate the internal and external structural components.
In the dimensioning, the choice is usually the axis of the chart requirements, it is important mounting surface, the contact surface (or the machined surface), some of the main structure of the closet symmetry aircraft (width and length), etc.,
Louboutin Classic Black win7 supervisor privileg, as size benchmarks. Box on the need for machining the part, should be as close as feasible to facilitate processing and inspection requirements to label size.
5. part general structure of the prevalent
Dimensioning Dimensioning holes (blind holes,
Christian Louboutin Mary Janes, screw holes, sink holes, countersink flat holes); Chamfer Dimensioning.
Blind hole
Threaded holes
Shen hole
Countersink holes
Ping
Down angle
1. introduced the notion of surface roughness and the main evaluation parameters
1) the concept of surface roughness on the surface of the part
with smaller peak spacing of the characteristics of the micro geometry of the composition, understood as surface roughness. This is primarily in the processing of parts, in part because of the tool marks left on the surface and the surface of the metal mowing separate formed by plastic distortion. Evaluation of surface roughness is also a part surface quality specifications, with the nature of its parts, work accuracy, dress resistance, corrosion resistance, sealing, appearance and so influential. Performance in ensuring the premise of the machine, in order to obtain the corresponding parts of the surface roughness, should be based on the character of parts, culling of appropriate processing methods to minimize production prices. In general, there are parts apply or a relative motion with the surface, the surface roughness parameter values to be small.
2) surface roughness of the code, symbols and commentary GB / T 131-1993 provides code and methods of surface roughness. Drawings, said part surface roughness symbols below.
3) Evaluation of surface roughness parameters
major assessment of surface roughness parameters:
1)) the arithmetic mean deviation of profile ( Ra) - the sampling length, the outline of the arithmetic mean of the perfect value of offset. Ra value and sampling length l table.
2)) contour highest elevation (Rz) - the sampling width, the contour lines and contours of the peak from the peak of the bottom line.
use preferred Ra parameter.
2. Surface roughness labeling requirements
4) surface roughness of the Code apparent a tall degree of surface roughness parameters of example
Ra, Rz, Ry merits marked in the code when using , in addition to code Ra parameter can be omitted, the repose necessary before the parameter values of the parameters of the corresponding code tag Rz or Ry,
Christian Louboutin Slingback, name instances in Table.
marking surface roughness of the surface roughness in the direction of numbers and symbols
5) surface roughness generation (symbols) in the pattern marked on the method of
1)) surface roughness generation (symbol) of the general should note that in the apparent contour, size, boundaries, or their extension ropes , the symbol of the cutting-edge substances, the point have to be from the surface.
2)) surface roughness of code numbers and symbols in the direction required to be marked.
3. surface roughness
example of the same mark on the drawing, each surface is marked only the premier generation (symbol) number, and as close as possible the dimension lines. When the space is small or inconvenience can guide to marked label. When all parts have the same surface roughness requirements, can be unified in drawing the upper right corner mark, when most parts of the surface roughness of the surface with the same request on behalf of one of the most warmhearted used (symbol) numbers can be Note the pattern while the upper right corner, and the word Where the uniform labeling of the surface roughness generation (symbol) of the text and the description of its mark in height should be 1.4 times the pattern.
part on the continuous surface, repeat elements (such as holes, teeth, slots, etc.) of the surface and chained with thin lines on the same surface of discontinuity, the surface roughness generation (symbol) of Note merely once.
the same surface with different surface roughness, the application of thin solid line
paint the line, and memorandum the corresponding code and the size of surface roughness.
gears, screw and so did not draw the tooth surface (dental)
shape, its surface roughness generation (character) of injection method shown in Figure.
megalopolis hole of the go surface, the keyway of the work surface,
chamfer, fillet surface roughness can simplify the code jot.
need to be part of local heat or local plating (coating) reiterate, the application of thick dotted line and marked
its coverage to draw corresponding size of the request can also be written in the surface roughness Note the long side of the cross symbol line.
2. standard tolerances and fundamental deviations
To facilitate creation, to attain interchangeability of parts and to encounter different requirements, the national standard standard tolerances and fundamental deviations of two elements. Standard tolerances to decide the size of tolerance zone, and the basic peccadillo tolerance to determine the location.
1) standard tolerance (IT)
standard tolerance values from the basic level to determine the dimensions and tolerances. Which is to determine the accurate size tolerance level degree mark. Standard tolerance is divided into 20, that is, IT01, IT0, IT1, ..., IT18. Accuracy of its size were decreased from IT01 to IT18. The specific value of the standard tolerances in the relevant standards.
2)
basic fundamental deviations in the standard deviation is with in limits and to determine the tolerance on the relative position of the zero line or lower deviation deviation , generally refers to the deviation approximate the zero line. When the tolerance zone is above the zero line, the basic error for the afterward deviation; the other hand, was on the bias. Deviation of a total of 28 basic, code, said the Latin alphabet, upper case for the hole, lowercase axis. Deviation from the basic catena can be seen that: the basic hole deviation A ~ H and the axis of the fundamental deviations k ~ zc for the next deviation;, hole deviation of K ~ ZC and the basic fundamental axis deviation a ~ h is the deviation, JS js tolerance and the zero line with a symmetrical distribution on both sides of the hole and the axis of the upper and lower deviation is + IT / 2,-IT / 2. Basic deviation array design only said that the position of tolerance, tolerance does not mean that the size, accordingly, tolerance zone is open at one end, beginning dissimilar Duanyou standard tolerance limits. fundamental deviation and standard tolerance, according to the meaning of dimensional tolerance has the emulating formula:
ES = EI + IT or EI = ES-IT ei = es-IT or es = ei + IT
hole and shaft tolerance zone code error code with the basic code with the tolerance level of the combination.
with the same elementary dimensions and medley of the aperture and shaft tolerance among, called the tie. According apt assorted application requirements, the cooperation between the hole and shaft are loose are tight, so the national standard with the type:
1) clearance fit hole and shaft assembly
, a gap ( including the minimum clearance zero). Hole tolerance area in the shaft on the tolerance zone.
2) transition with
hole and shaft assembly, there may be gaps or interference in the match. Hole tolerance zone with the axis of tolerance zones overlap every other.
3) the interference eligible hole and shaft assembly
interference at times (including the minimum interference zero). Hole tolerance zone below the axis of the tolerance zone.
benchmark system:
in manufacturing with the parts,
Cheap Christian Louboutin, so that one of the parts as the base chips, and its basic error must,
Christian Louboutin D'orsay, by changing to another The basic types of non-reference items to obtain a variety of different types of error with the system is called base system. According to actual production needs, national standards for the two benchmark system. 1) The hole basis system (shown below left hand side)
hole basis system - is the fundamental error for a certain hole tolerance zone axis deviation with different basic form of the tolerance zone category with a system. See below left. Hole hole basis system is called base hole, the basic error code for the H, the retinue error is zero.
2) the axis system (as shown below right)
basic shaft system - is the fundamental axis discrepancy is a certain tolerance orchestra and the hole discrepancy of different basic tolerance for manifold forms of cooperation with a system. See below right. Axis of the axis as reference axis system, the basic error code is h, the upper discrepancy zero.
With the code with the code
by the hole and shaft tolerance zone code form, written in fragment form, the molecular code for the hole's tolerance zone, the denominator of the axis of the tolerance zone code. All particles involving H, with the found hole system, entire embodying h, the denominator of the axis system for the cooperation.
example φ25H7/g6 is the signification of the basic size of the complex φ25, the clearance fit hole root system, the benchmark for the hole tolerance H7, (the basic level of tolerance for the deviation of H 7), the axis of the tolerance band g6 (fundamental deviation g, tolerance grade 6).
example φ25N7/h6 is the averaging of the basic size of the complicated φ25, the axis system of the transition with the reference axis of the tolerance zone for the h6, (fundamental deviation h, tolerance grade 6), the hole tolerance zone for the N7 (fundamental deviation of N, tolerance level is 7.)
tolerance and marked aboard drawings with
1) marked on the assembly drawing tolerance and fit, the use of combined injection means.
2) in part drawing on the form marked in three ways.
4. geometric tolerance
parts processed, not only in size of the error, and will have geometry and joint position error. Cylinder, even when passing in size, there may be one end of the great, small or medium of the other side of both ends of thick and so nice, its not a round cross-section is also possible that the error is shaped area. Stepped shaft, the shaft may occur after processing segments of different axes, and this is in locating errors. Therefore, the shape of tolerance is the actual shape of the ideal shape to grant changes in volume. Position tolerance is the actual location of the ideal position to grant changes in volume. Both short form and position tolerances.
Geometric Tolerance bullet
1) shape and position tolerances of the code
national standard GB / T 1182-1996 as stipulated in the code to mark the shape and position tolerances. In actual production, when not marked with the code when the geometric tolerance, allowing the technical requirements used in the text. Geometric Tolerance Code include: the intention of geometric tolerance symbols, geometric tolerances and guidelines grid box line, form and position tolerance values and other relevant symbols, and the reference code and so on. Frame height h in font size and pattern in the digit of contour.
2) examples of geometric tolerancing
a valve stem, marked in the figure in the vicinity of geometric tolerance add text, equitable to give readers written on the note and repetitive, the pattern in the actual writing in the note need not be reiterated.
1. the part of the cast structure
1) As part of the cast rounded
rowdy for casting, for casting process requirements, the casting of the surface intersection should be made of rounded edge. Casting casting casting when rounded the corner to prevent the falling sand and avert the phenomenon of metal cooling shrinkage and crack generation. The size of fillet molding generally the R = 3 ~ 5mm, can be specified in the technical requirements of the uniform.
2) from the model gradient method of fabrication at casting
rough parts, in mandate to facilitate the exterior of the sand removed, usually made by the intention of chart to look about 1: 20 incline, called the Taper Angle. Therefore, there is also a corresponding casting Taper Angle, this tilt can not be marked on the map, not necessarily draw, as shown below; necessary, the technical requirements can be used in the text.
3) casting thickness of the uneven thickness
line when casting, the casting in the casting, the cooling rate deserving to the different parts of the metal, will produce cracks and shrinkage phenomenon. Therefore, the casting wall thickness should be as even as possible, see above; when connected to a different walls thickness, the transition should be gradual access, see above. Wall thickness of casting out the general use of direct injection.
2. parts machining on the structure of
1) back groove and more process slots
wheel cutting in part, in order to facilitate the exit of knives and related parts during assembly to ensure namely the contact surface try to be, in the surface steps is processed at the pre-processing of the reimburse shall be groove or more wheel steer slot. Cylindrical rotating back when the groove, and its size is generally can be Cylindrical or cylindrical grinding and face grinding wheel when the more process slots.
2) drilled with a drill hole structure
blind holes in the bottom of a 120 ° cone angle, drilling depth refers to the cylindrical part of the depth, not including cone pit. In the ladder-shaped hole by the transition, there are cone angle 120 ° round table, the drawing and Dimensioning.
drilling with a drill when the drill morsel axis as required to be drilled perpendicular to the face, to assure precision and avoid the drilling bit broken. The correct structure of three drilling face.
3) and the pit employer
parts with other parts of the contact surface, are generally required processing. To reduce the processing place, and to ensure a nice part surface contact between the often designed on the casting boss, pit. Bolt support surface or support surface pit boss in the form of; in order to reduce processing area, and make grooves.