Solder the structure ruptures control and integrality

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Current, solder the technology receives wide application in the production of structure of plane, engine. Solder advancedly production technology can obtain excellent welding line and tall dimension precision already, also satisfied plane structure whole gender and light quantified requirement, but also raised new question in structural integrality respect. Solder the structure is being made in reaching moving process, exist inevitably or appear deterioration of function of organization of various blemish, material, and the outside force injury ingredient that makes an impact to structural performance characteristics. Enlist in army as the structure especially the addition of time, all sorts of accumulation that injure an element are brought about destroy probability to rise. Rupture control is to solder the key of structural integrality, it is to solder the structure closes at use base. Solder of the structure rupture control basically is to show to soldering through studying all sorts of factors structural intensity, wear is mixed the influence that mars the performance such as tolerance, solder to the influence thereby all sorts of elements of structural integrality undertake discriminating integratedly, scientific assessment solders the structure is potential the possibility of invalidation, implementation to soldering structural integrality manages, solder in order to assure of the structure close at using. Solder the structure closed to get greater progress in recent years at using assess technology, in assure to solder structural security aspect produced main effect, produced remarkable economy and social beneficial result. Solder according to our country aviation the need that the structure admits, begin solder the structure ruptures control and integrality research and application, to making sure aviation solders structural security and economy have important sense. Solder integral sex of the structure and not integrality is like riveting structure photograph to compare with other join structure, solder integral sex of the structure is strong, tigidity is big. Solder the structure is the whole that solders to contact joins and be become by what cannot disassemble, join between produce opposite displacement very hard, because this causes greater additional stress easily, make of the structure fight rupture ability is reduced. Solder its are opposite rigid ambassador of the structure stress concentration is very sensitive, reduce when working temperature especially when, stress can increase structural happening centrally fragile the dangerous sex that break. Solder integral sex of the structure made reasonable construction offer a possibility for the design. But if solder structural happening craze, crackle is expanded very easily by a component another component, then expands structural whole, cause structural whole to destroy. However riveting structure produces whole not easily however to destroy, because riveting connect is had,prevent crackle to span the characteristic with patulous component, expand medium crackle may be stopped namely, avoid disastrous brittleness likely to destroy thereby. Accordingly, in a lot of large solder in the structure, still withholding sometimes a few riveting connect, its truth depends on this. Application solders while the technology creates integral structure, also can arise local not integrality. Solder of the structure not the discontinuous sex that integrality basically has stuff or weld defects. The stress that the influence that weld defects ruptures to the structure and blemish cause centers the material function near degree and blemish to concern. Affect rate according to what blemish ruptures to the structure, can be weld defects cent plane blemish, bulk blemish and shape undesirable 3 sort: Planar blemish, if crackle, incomplete fusion is mixed not solder is appeared etc. This kind of blemish depends on to the influence that rupture the intense rate of the size of blemish, orientaton, position and blemish forward position. Blemish face is perpendicular the surface and the blemish at stress direction, close surface blemish and the crackle with acerb forward position, the biggest to the influence that rupture. Bulk blemish, wait like stomatic, slag inclusion, they are general to the influence degree that rupture under planar blemish. Shape undesirable, if the Yu Gao of solder path crosses big or insufficient, horn to be out of shape, or wait by the side of the fault that welding line is in, they can bring stress concentration or additional stress to the structure, to soldering of the structure rupture intensity produces adverse effect. Solder whether does the blemish in the structure allow to exist, have two kinds of big criterion for evaluation at present, it is the standard that is a foundation with controlling quality firstly; It is the standard that is a foundation with according with use requirement secondly, say again " close at using a principle (Fitness For Service, FFS) " . Former it is premise with corresponding strength condition, latter is with rupturing mechanical theory is a foundation. Generally speaking, soldering in structural production process must carry out concerned quality strictly to control a standard to decide whether does blemish allow to exist, if the blemish of discovery did not exceed quality to control the limit that standard place sets, criterion blemish allows to exist; If the blemish of discovery exceeds formulary limit, criterion blemish does not allow to exist, need has repair. Quality control level is right of blemish decide, blemish of very difficult consideration uses the act in the process in the structure, calculate the repair impact to structural function very hard also. "Close at using a principle " the action that is function of integrated consideration material, blemish and load condition to the assess of blemish, the influence of the odd intensity with assess periodic to structural life blemish, decide whether blemish can be accepted. Quality control standard and close to be able to be used at using a principle, in structural production process, if accord with quality to control standard demand, to fragile break the structure with dangerous not high sex to need not be pressed close to undertake assess at using a principle; And the structure that asks to having Gao Ke to rely on a gender, should reach odd life basis to close to undertake assess at using a principle to blemish tolerance of the structure. If flaw discovers in structural use process, need to use close to undertake assess to blemish at using a principle. Close at using assess it is to solder the core that structural integrality analyses. Solder the structure ruptures control design control solders the main factor that the structure ruptures has 3 sides: (1) material is mixed in rate of constant working temperature, to load board the fracture toughness below thick condition; (2) the structure ruptures the crackle of weak position and blemish dimension; (3) include concentration of working stress, stress, leftover stress and temperature stress inside pull stress level. The basis ruptures mechanical principle, when the specific combination of afore-mentioned tripartite face elements achieves critical status, the structure can happen rupture destroy. Solder of the structure rupture include crack since crackle, stable state expands and break firm rupture process, control solders the basic method of the structure that rupture and this answers relatively, namely: (1) the metal of mother capable person that chooses to have enough tenacity and welding line metal, with counteractive crackle case crack, fight craze ability namely; (2) once be cracked since crackle, material should have the capacity that prevents crackle to expand further all round its, crack ability to crackle stops patulously namely. The craze that controls crackle (case crack) with expanding is to solder the structure ruptures pilot is basic criterion, cent another namer produces standard to avoid flaw (craze is controlled) and stop crack criterion (patulous control) . Solder of the structure rupture destroy the effect that suffers the many sided element such as design, select material, workmanship, use environment, rupture to control is designed even if design a system according to the intensity that ruptures to build a system theoretically, its design criterion to consider conventional strength and stiffness on one hand, emphasize a structure again on the other hand fight rupture function. Its core is safeguard structure the integrality in use process and dependability. Systematic structure ruptures the main content that controls a design includes: (1) all element that decides structural whole or integrality of crucial component part in detail; (2) qualitative or the effect that ration analyses each element to rupture to structure or component; (3) make design, craft, installation, examine, safeguard inflict waiting for arrange to decrease rupture possibility; (4) the harmony that emphasizes each respect, each link and collaboration, enact firm control order and constituent measure. Nextpage basis solders the structure ruptures control designs a principle, solder contact must be had fight enoughly rupture function and odd intensity, set in order to make the structure is in the load that can foreknow and ambient conditions can bear inside life period (include statistical variability) action. Should prove to solder of contact fight rupture property is enough need to use an experiment to undertake assess. Solder the application that structural integrality and technology of integrality of working job structure are designed in the structure of contemporary aviation engine, plane and receives succeeding most in test and verify. According to the definition with general and normative structure of plane of air force MIL-A-87221, allowance of the intensity that structural integrality is the airframe structure that points to an influence to aerostat safety is used and use fee, stiffness, loss, wear and function, namely structural integrality is the security that assures a structure and economy, the target that considers is structure and its component, involved main content considered conventional strength and stiffness requirement on one hand, emphasized wear and scathing allowance again on the other hand fight rupture function, ask from this two respects assure use function of the structure at the same time, accordingly this method has systematization, whole gender and omnibus. Structural dependability and security rely on structural integrality greatly, structural integrality is by material function, structure tectonic, workmanship, load and environment, use with safeguard those who wait for a variety of elements to decide. Solder structural integrality still lacks specific definition, according to concept of contemporary structure integrality, can think to solder structural integrality is to solder structural applicability or close at using a sex. Solder by what international Institute of Welding rolls out of the structure close to be defined at using assess guideline, close at using it is to show the structure is in regulation have inside life period enough can bear the load that can foreknow and ambient conditions (include statistical variability) function. Close namely at using it is the target that structural integrality asks to want to achieve, and the function that how proves a structure or capacity are sufficient, it is the content that place of structural integrality assess should explore. Can think according to the definition of structural integrality structural integrality assess must analyse influence structure safety in the round advocate control an element, master structural place to bear in detail the main form of load and ambient conditions and its invalidation, be opposite then of structural details mechanical answer undertake comprehensive analysis with local and mechanical function, assess a structure thereby close at using a sex. Solder one of marked characteristics of the structure are integral sex strong, solder structural integrality should assure to solder namely the structure carries outside bear and the integral sex below environmental action asks. Solder the stiffness of the intensity that integral sex of the structure asks to include contact, structure and stability, fight rupture gender and wear. Solder the performance of contact is uneven gender, welding stress and be out of shape, the element such as concentration of contact detail stress, weld defects the effect that to soldering structural integrality has different rate, mature these elements are to solder the key content that structural integrality analyses. Solder structural integrality is main the task includes to solder the structure is destroyed (or invalidation) mode analysis, risk analysis and integrality evaluation. Integrality answers relatively with injury, scathing degree produces an effect to structural integrality, the function that injury is a structure degrades process, its limit is invalidation. And the cause that causes loss is load of structural place susceptive and environment it is dangerous to all sorts of forming (or risk) element. Accordingly, solder the integrality that the key of structural security is a structure, research solders of invalidation mechanism of the structure and risk problem is the integrality that assures a structure at all. In recent years, management of engineering construction integrality is taken seriously in the world by height. Structural integrality management stresses detected application particularly, the check-up that if colleague,detects, examine scathing case of the structure namely, diagnose for integrality offer " illness " . Solder the structure exists in the hard to avoid in production process metallurgy and mechanical blemish, solder concentration of leftover stress, stress, and other is likely the loss that the element causes, make solder the structure already had fixed rate before investment is used not integrality, formed solder the initiative condition of structural integrality. Soldering in structural moving process, because work,the element such as environment and load forms the inducement that injures development, the formation that scathing accumulation can bring about crackle and patulous, crackle expands critical dimension is formed rupture, this one process is to solder structure by initiative condition to destroy (or invalidation) of condition evolve. Structural integrality is analysed even if want monitoring to solder the metabolic process of the integrality condition of cycle of structural whole life, accordingly, solder structural integrality analysis also can call integrality condition to analyse. Integrality is to solder the serious content that cycle of structural system whole life manages. Arrive from structural design make, and use and safeguard wait for each phase to need to establish specific working plan. The integrality job job that arranges each link with the form of guiding outline is in plan of contemporary structure integrality. Solder integrality plan of the structure should ask according to the function of product structure, designing, make, use reach safeguard each phase to make specific analytic means, test the specific work content such as criterion for evaluation, solder in order to assure integrality target of the structure. Solder according to the influence the element of structural integrality and rupture control requirement, can induce piece solder the main job content that structural integrality plans. Integrality is to solder the structure closes at what use important assure the economy according to engineering construction but endurance requirement, the usability that integrality should assure a structure (applicability or close at using a sex) . Solder structural integrality and close at using a sex both have difference already, it is unified. Solder the target of structural integrality is do one's best will rupture invalidation risk lowers minimum, close at using a principle if where,be a consideration the function that economy can assure a structure below susceptive condition. The integrality that assures a structure is to ensure close at use base. Solder of the structure absolutely and complete often accomplish very hard, its are complete the standard that degree is accepted is to close at using a sex, perhaps say its injure degree not to affect performance characteristics. Close to solder at using assess to analyse injury to be opposite namely the influence of structural integrality, solder certainly whole level of the structure. Accordingly, close at using assess it is to solder one of main content that structural integrality studies. Current, solder method of structural integrality assess is to build closing to go up at using the base of the principle. Soldering structural development is earlier, requirement structure all cannot have any blemish to exist in make and using a process, namely structure should apple-pie, be about otherwise repair or discard as useless. Consider to make clear in great quantities later, although solder,certain blemish exists in contact, and to soldering the impact of the intensity of contact is very little, and repair meets those who cause structure or contact performance characteristics reduce however, accordingly, appeared " close at using " concept. In rupture mechanical after appear and applying extensively, this one concept more got the attention of people and take seriously, become solder the main task that structural integrality studies, already developed gradually now become a principle, content also gets plenitude gradually, and had specific definition. Suffer destructive risk to reduce structural integrality, reduce a structure to destroy the happening of the accident, must undertake analysis and integrality are evaluated rupturing, or say blemish assess is reached close at using assess. Close at using assess it is an analysis solder the actual condition of the integrality that the structure issues in action of a lot of and critical factor, reach its and initiative condition, before one position critical (invalidation) condition undertakes comparative, in order to decide the evolution circumstance of actual condition and integrality. On this foundation, offer integrality monitoring measure, ensure solder structural safety moves. Close to call a project critical analysis again at using assess, be in order to rupture mechanical, play plasticity mechanical the project that reachs dependability system project to be a foundation analyses a method. In production process the structure appeared blemish, basis " close at using " the principle decides whether this structure can be checked and accept. In structural use process, whether does the flaw that assess place discovers allow to exist; Solder newly in the design when the structure, stipulated blemish is acceptable standard. Since abroad is long-term began extensively rupture the research that assesses a technology works, formed in order to rupture mechanical be a foundation close at using assess method, concerned application already produced remarkable economic benefits and social beneficial result. Many countries had been built solder structural design, make and acceptable close at using a standard, become solder structural design, make, the complement that checks and accept relative standard. Rupture control and integrality assure is to solder the main job that cycle of structural whole life manages, to soldering the safety of structural system has important sense. Solder of the structure close to have systematization at using evaluation technology, omnibus with scientific sex, its concept and method solder in our country aviation structural application respect still is in start level. Solder according to aviation real need of the structure, answer to begin concerned research and promotion work actively, to build our country aviation to solder structural integrality evaluates a system to provide a basis. CNC Milling