GB/T 1800.1 limit and cooperate a foundation

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1 overview is contemporary spare parts of machine of machinist trade demand has interchangeability, so that be not mixed via the choice when assemble,make repairs and supply replacements can be achieved anticipate cooperate function, be helpful for machinist job organizing extensive efforts thereby, undertake specializationing efficiently manufacturing. To make mutual assembly parts has interchangeability, the consistency that must make sure appearance of its dimension, geometry and mutual position and technology of exterior surface roughness ask. With respect to dimension character, consistency of interchangeability requirement measure, but this is not to ask the spare parts of all and mutual combination wants finally to unite treatment the exact size that specifies to, is to ask its are final only size lies inside the dimension range with reasonable some can. Scope of this reasonable size is the relation that shows it is certain to can make sure mutual union is formed between spare parts dimension already, satisfy different use requirement, can make sure its are being made again going up is economy is sound. This was formed " the limit and cooperate " concept. "The limit " use at coordinating machine spare parts to use requirement and the contradiction between production economy; "Cooperate " it is report when the spare parts is combined mutual the relation between. "The limit " with " cooperate " standardization, the design that is helpful for a machine, make, use and maintain; Be helpful for assuring each use requirement such as product precision, performance characteristics and life; Also be helpful for the standardization of the tooling such as cutting tool, measure, clamping apparatus, machine tool. Because of this international Organization for Standardization (all through the ages of each main industry country is opposite ISO) and world " the limit and cooperate " standardize those who give height to take seriously. ISO is concerned at was being released 1962 " the limit and cooperate " the first recommends ISO/R 286-1962 of sexual international standard " ISO limit and cooperate to control base of the 1st part tolerancepublic errand and cooperate " later, each country edited in succession native standard, used new international limit system. To get used to the development of contemporary and mechanical industry, ISO/TC3 " the limit and cooperate " technical committee was in charge of undertaking editing to ISO/R 286, issued two new international standards early or late 1988: ISO 286-1: 1988 " ISO limit and cooperate to make -- the 1st part: Tolerancepublic errand, deviation and assorted foundation " ; ISO 286-2: 1988 " the limit and cooperate to make -- the 2nd part: Extreme deviation numerical value expresses grade of standard public errand and aperture, axis " . Older edition ISO/R 286 basically has new edition ISO 286 to change below on the look inside: Revised a criterion weave, make drawing office and workshop both all can use ISO 286 directly. New edition ISO 286 makes ISO " foundation " with " the computation of standard public errand and basic error is worth " apart, gave out the ultimate numerical value of the most commonly used public errand and deviation is expressed; Use to promote deserve to have demarcate character implement device symbol, replace former code name Js and JS with Js and JS. Letter " S " and " S " represent " symmetrical deviation " ; According to real need, included basic measure to come from 500mm the standard public errand of 3 150mm and basic error (it is try out) only before; Increased IT17 of grade of two standards public errand and IT18; New edition ISO 286-1 moves the IT01 of grade of standard public errand in text and IT0 to the appendix in. Our country begins equivalent to use ISO 286-1 from 1994: 1988 pairs of GB 1800-79 " tolerancepublic errand and cooperate topical standard public errand and basic error " undertake editing. When editing, consider will edit again henceforth its need not be involved when certain part of the standard whole level, and consult and use of facilitating standard, and decision general translate into of this international standard is the following 3 new GB: GB/T 1800.

1-1997 " the limit and cooperate a foundation the 1st part: Vocabulary " (replace GB 1800-79 " term and definition " partial) ; GB/T 1800.

2-1998 " the limit and cooperate a foundation the 2nd part: Tolerancepublic errand, deviation and assorted main provision " ; GB/T 1800.

3-1998 " the limit and cooperate a foundation the 3rd part: Standard public errand and basic error numerical value are expressed " . 2 GB/T 1800.

GB/T 1800 of 1 introduction new edition.

1 " the limit and cooperate a foundation the 1st part: Vocabulary " the appendix that includes standard text and a reminder. Text gave out the limit and 39 when coordinate an aspect basic technical terms and definition; The appendix gave out to list Chinese term with this standard place equivalent English, French and Russian term. English, French and Russian are the legal work language of ISO. New edition GB/T 1800.

1(abbreviation new GB) press accurate, rigorous, consistent, ask with what international standard unites, to old edition old GB of GB 1800(abbreviation) term definition and legend made bigger modification. To lexical section section, weave also made bigger adjustment. The appendix that increased a reminder -- equivalent term. New GB set 39 term in all, among them new addition term has: Local and real measure, limit system, cooperate to make, the biggest hypostatic limit and the smallest hypostatic limit, in all 5. The others 34 term and old GB are consistent. 6 term such as the the the largest hypostatic position that old GB sets, Least Material Condition, largest hypostatic size, smallest hypostatic size, mating size of bore and mating size of shaft, because there already was a regulation in other and relevant GB, reason did not include new GB. Reach a definition to make one brief introduction to 39 term in new GB below. About " aperture " , " axis " , " dimension " term defines Kong He axis: These two basic technical terms are in aperture and axis the limit and there is specific meaning in coordinating a standard, they involve the limit and the applied range that cooperate GB. Aperture: Normally, those who point to workpiece is cylindrical inside the surface, also include to be not cylindrical inside the surface (include by what 2 parallel plane or tangent plane form face) . Axis: Normally, those who point to workpiece is cylindrical outside face, also include to be not cylindrical outside face (the) of face be includinged that forms by 2 parallel plane or tangent plane. The level is right blame inside cylindroid, outside face also regards as " aperture, axis " . For example the chamfer of keyway is wide be form by 2 parallel plane inside the surface, regard as " aperture " ; The width of key is the outside range that makes by 2 parallel plane, regard as " axis " . The limit and the aperture in coordinating a standard, rod is made by single measure. For example: The width of the diameter of cylinder, key and chamfer. To a square aperture, when be restricted with dimension public errand, must decompose it for length and width two single measure, give common difference respectively. If the understanding to meaning of aperture, axis looks from both combinative concern, aperture is to include face, the axis is face be includinged; From the point of the treatment of workpiece, as treatment undertake, the dimension of aperture by small greaten, axial dimension by big decrescent; From measure in light of, the measurement technique of aperture, axis also differs somewhat. Dimension: Represent the numerical value that linear dimension is worth with specific unit. Dimension is one of the basiccest technical terms in the standard. Size represents the bulk of length, include diameter, length, width, height, ply and center to be apart from, round horn radius, it is mixed by the number length unit (if Mm) is comprised. The dimension that tags in technical cartography regards unified length as the unit with Mm normally, can keep a number only, do not keep an unit. It does not include to use angle unit denotive angle dimension. Basic measure: Go up through its application, next deviation but the dimension of size of cipher out maximum. Basic measure is the need according to spare parts function or structure, decide after the requirement that considers craft aspect. Basic measure can be an integer or a little numerical value, recommend by the standard (GB 2822-81) chooses basic measure and tag on the design. Real measure: Through measuring the size of acquisition some hole, axis. Local and real measure: The either in the aleatoric cross section of an aperture or axis is apart from, namely the measure that any two-phase get to be being measured between the dot. Because existence measures an error, so real measure is not the true value that is dimension. This explains, in real measure the bag is contained those who allow measure an error. Mix about the bulk that allows to measure an error how to wait for a problem certainly, GB/T 3177-1997 " of smooth work measure examine " already made specific provision. Actually, still have a factor that affects real measure, this is appearance error. As a result of the existence of appearance error, on workpiece everywhere real measure often is different. Ultimate size: Two extremes of the measure that an aperture or axis allow. Real measure is located in among them, also can reach ultimate size. The largest size that aperture or axis allow is size of the biggest maximum, the smallest size that aperture or axis allow is size of the smallest maximum. Ultimate size decides with basic measure for base. It is an architect in affirmatory and basic measure while, of to satisfy some kind to use the requirement that go up make choice of. For example, to make the axis can be in Kong Zhong turns, answer to provide the ultimate measure of aperture a few more greatly, the ultimate size of corresponding axis should set a few smallier than aperture. Actually, press workpiece examine the system undertakes examining, no matter use methods of which kind of check proved recipe, it is existing to measure an error, so ultimate size is not the real limiting value that allows dimension to change, however its nominal value. Same argument, the the common difference that mentions below, extreme deviation, least space (or be filled with too) , the biggest gap (or be filled with too) and fits tolerance is waited a moment, it is the nominal value that points to them commonly. About " limit system " , " deviation " , " tolerancepublic errand " term defines limit system: Via the public errand of standardization and deviation system. 0 lines: In the limit and cooperate graphic in, a when show basic measure linear, it is fiducial and affirmatory deviation and public errand with its. Normally, 0 lines make the same score directional scale along water, deviation is located in on its, negative deviation is located in his to fall. Deviation: Some dimension (real measure, maximum size, etc) decrease its the algebra of basic measure income is poor. Size of the biggest maximum decreases his the algebraic difference of basic measure income is on deviation; Size of the smallest maximum decreases his the algebraic difference of basic measure income is next deviation; Deviation calls extreme deviation with next deviation all on. Real measure decreases his the algebraic difference of basic measure income is factual error. Because ultimate size is mixed,be equal to basic measure, so deviation can be be worth or lose a value or 0. Factual error should be located in in extreme deviation limits. Extreme deviation is used at restricting factual error, its size affects the degree of tightness that the spare parts cooperates to spend directly. Basic error: In this standard the limit and in cooperating to make, affirmatory public errand takes that extreme deviation relative to 0 lines position. It can be to go up deviation or next deviation, it is that deviation that stands by 0 lines commonly. It is when tolerancepublic errand belt when 0 lines upper part, its are basic deviation is next deviation, it is when tolerancepublic errand belt when 0 lines lower part, its are basic deviation is on deviation (graph 1) . Graph public errand of dimension of sketch map of 1 basic error () of abbreviation public errand: Size of the biggest maximum decreases the difference of size of the smallest maximum, or go up the difference that deviation decreases next deviation. It is the variation that allows measure, it is an absolute value that does not have a symbol. Tolerancepublic errand is dimension precision and a kind of magnanimity that cooperate precision. Common difference is less, the precision of the spare parts is taller, the permission of real measure variation is less also. Consequently, its cooperate clearance (or be filled with too) allow variation smaller, assorted precision is taller. Conversely, spare parts common difference is bigger, dimension and cooperate precision lower. Tolerancepublic errand is used at restricting on size error, it affects assorted precision. Standard public errand (IT) : This standard limit and the either noncombatant duty that in cooperating to make, set. Letter " IT " (International Tolerance) is " international public errand " symbol, namely the symbol of standard public errand. Grade of standard public errand: In this standard the limit and in cooperating to make, grade of same public errand (for example IT7) is thought to have coequal and exact rate to a group of public errand of all and basic measure. That is to say the exact rate that its in order to determines size. Factor of standard public errand (I, i) : In this standard the limit and in cooperating to make, in order to decides the main unit of standard public errand. This factor is the function of basic measure. Old GB calls tolerancepublic errand unit. Factor I uses standard common difference at basic measure to 500mm; I is used at basic measure to be more than 500mm to 3 150mm. Grade of standard public errand and basic measure section, public errand and tolerancepublic errand factor are concerned, row type expresses to be: In type of F(D) of = of IT = A*i(I) I(I) : A -- coefficient of tolerancepublic errand grade; I(I) -- tolerancepublic errand factor; D -- basic measure. Tolerancepublic errand belt: Take in tolerancepublic errand graphic in, by definitive of two of the deviation on the representing and size of next deviation or size of the biggest maximum and the smallest maximum linear place an area. It is like basic error to decide relative to the position of 0 lines with its by tolerancepublic errand size. In " the limit and cooperate to make " in, tolerancepublic errand belt is a very main idea. Analyse a problem to facilitate, the common difference that draws the magnified aperture that closes suitably and axis only normally takes a picture, this is the limit is as graphic as what cooperate, abbreviation is taken for tolerancepublic errand graphic. When belt of picture public errand is graphic, customarily draws one abscissa to show basic measure first, this line is 0 lines. Next on the basis, next deviation draw an aperture respectively or axial public errand is taken. the upper part that deviation is located in 0 lines, negative deviation is located in the lower part of 0 lines. If pursue,2 are shown. Graph 2 aperture and axial public errand take graphic signal this shows, tolerancepublic errand belt is by " tolerancepublic errand brings volume " and " tolerancepublic errand takes the place " two element comprise. Tolerancepublic errand takes size to pursue namely 2 in tolerancepublic errand takes the width on as perpendicular as 0 lines direction, decide by standard public errand; "Tolerancepublic errand takes the place " pursue namely 2 in tolerancepublic errand takes an edge 0 lines are perpendicular the positional coordinate on direction, decide by basic error. About " cooperate " , " cooperate to make " term defines clearance: The difference of the dimension of the axis that subtractive photograph coordinates the measure of aperture is. In clearance fit, the size of the smallest maximum of aperture decreases the difference of size of the biggest maximum to be the least space. In clearance fit or transition fit, the size of the biggest maximum of aperture decreases the difference of size of the smallest maximum to be the biggest gap. Be filled with too: The difference of the dimension of the axis that subtractive photograph coordinates the measure of aperture is negative. Had been in be filled with in cooperating, the difference of the size of the smallest maximum that the size of the biggest maximum of aperture reduces an axis is most peccadillo is filled with. Had been in be filled with cooperate or in transition fit, the difference of the size of the biggest maximum that the size of the smallest maximum of aperture reduces an axis is most the serious offence is filled with. From the point of standardization angle, new GB united pair of clearance and the definition that are filled with too. Unite the measure that uses opening to subtract the dimension gain that closes an axis suitably is differred, negative symbol will decide the property that its cooperate. If income difference is, show gap, income difference is negative, had expressed to be filled with, its absolute value is gap amount and interference. For example, income difference is " + 20 " , state clearance is measured for 20; Income difference is " - 20 " , state interference is 20. Cooperate: Basic measure is same, the aperture of mutual union and axial public errand head the concern between. Here " cooperate " having specific meaning: The union of aperture and axis, have the concern that include and is included; The basic measure that combines aperture, axis each other is same; Assorted degree of tightness is spent, basically concern with the size of meantime unoccupied place quantity or interference, the mutual place that takes with public errand of aperture, axis namely is concerned; Cooperate degree of tightness to spend, the size that cooperates belt of public errand of precision and aperture, axis namely is concerned. Before 2 o'clock is assorted condition, hind reflected assorted nature at 2 o'clock. The place that ties belt of public errand of aperture, axis each other affects, decide its cooperate property: Clearance fit, transition fit and be filled with too cooperate. Clearance fit: Have space (include the least space to be equal to 0) cooperate. Right now, the tolerancepublic errand belt of aperture is over tolerancepublic errand belt of the axis. Transition fit: The likelihood has space or be filled with too cooperate. Right now, the tolerancepublic errand belt of the tolerancepublic errand belt of aperture and axis is handed in each other fold. Be filled with too cooperate: Had had be filled with (include most peccadillo is filled with be equal to 0) cooperate. Right now, the tolerancepublic errand belt of aperture is under tolerancepublic errand belt of the axis. Look from use requirement, want to control clearance or the bulk that are filled with too not only, what control clearance even or be filled with size too is fluctuant, this put forward " fits tolerance " concept. Fits tolerance: Comprise the sum of public errand of assorted aperture, axis. It is permissible clearance or the variation that are filled with too, it is an absolute value that does not have a symbol. Cooperate to make: The aperture of same limit system and axis form a kind of compositive system. The foundation that cooperates series is base aperture is made cooperate to be made with basic shaft cooperate. Base aperture makes cooperate: Basic error is the tolerancepublic errand belt of certain aperture, take a kind of system that forms all sorts of cooperating with the public errand of the axis of different and basic error. In new GB the limit and in cooperating to make, base aperture is made cooperating is the basic error with aperture is fiducial, come to those who get all sorts of different quality cooperate through changing basic error of the axis. Base aperture makes assorted Kong Weiji follow opening, the basic error of fiducial aperture (next deviation) for 0. Basic shaft makes cooperate: Basic error is the tolerancepublic errand belt of certain axis, take a kind of system that forms all sorts of cooperating with the public errand of the aperture of different and basic error. In new GB the limit and in cooperating to make, basic shaft is made cooperating is the basic error with the axis is fiducial, come to those who get all sorts of different quality cooperate through changing the basic error of aperture. Basic shaft makes assorted axis be fiducial axis, the basic error of fiducial axis (go up deviation) for 0. About " hypostatic limit " term definition sets out from the concept of hypostatic limit, new GB raised the biggest hypostatic limit and the smallest hypostatic limit two new term. The biggest hypostatic limit (MML, maximum Material Limit) : Corresponding at aperture or axis that maximum size of the largest hypostatic size, namely: The size of the smallest maximum of size of the biggest maximum or aperture. The largest hypostatic size is to point to what have in aperture or axial place to allow data capacity to be most the ultimate size when. The smallest hypostatic limit (LML, least Material Limit) : Corresponding at aperture or axis that maximum size of the smallest hypostatic size, namely: The size of the biggest maximum of size of the smallest maximum or aperture. The smallest hypostatic size is to point to what have in aperture or axial place to allow data capacity to be least the ultimate size when. About the standard advocate the modification of caption is new GB gave out limit system and cooperate to make two term definition. Limit system and cooperate to make both form the limit and cooperate to make. The standard of old GB advocate caption -- " tolerancepublic errand and cooperate " the whole content that already cannot generalize this respect to standardize, because tolerancepublic errand is one of limit system only, new GB will be consequently old of GB advocate caption repairs instead " the limit and cooperate " , this covered the content of new GB already, agree with international standard photograph again. GB/T 1800.

The definition uses the term of 1 regulation to assure pair of concerned limits and the uniqueness that cooperate to respect term is stated and understand, involve the limit and the each technology standard that coordinate basic vocabulary and file and publication accordingly make or write the regulation that should follow new GB. CNC Milling