飞机装配翻译

2004-01-2832 Determinate Assembly of Tooling Allows Concurrent Design of Airbus Wings and Major Assembly Fixtures John Hartmann, Chris Meeker, Mike Weller, and Nigel Izzard Copyright . 2004 Society of Automotive Engineers, Inc. ABSTRACT Most new aircraft programs encounter the challenge of balancing the time required for design optimization with product delivery constraints. 大部分新的飞行器项目都面临着平衡优化设计所需的时间和产品交付期限之间的矛盾。The high cost and long lead times of traditional tooling makes it difficult for aircraft manufactures to efficiently meet ever-changing market demands. 成本高和用时长的传统飞机工艺装备使得飞机制造商很难有效满足不断变化的市场需求。The large size, low relative stiffness and high positional tolerances required for aircraft components drive the requirement for rigid fixed tooling to maintain the precision part relationships over time. 飞机部件所需的大的外形，小的相对刚度和高的位置容差驱使着对严格刚性装配的需求向长时间保证各部分精确关系的转变。Use of todays advance 3-Dimensional CAD systems coupled with the high accuracy of CNC machines enables the success of the determinate assembly approach for aircraft tooling. 对当今先进3D CAD系统及高精度CNC机床的运用使得刚性装配在飞机加工上取得成功。This approach provides the aircraft manufacturer significant lead-time reductions while at the same time it supports enhanced system flexibility. 这种方法给飞机制造者带来显著的lead-time间隔时间的减少，同时还支持增强的系统柔性。Determinate assembly for aircraft tooling has proven to be highly successful for tooling manufacture on large-scale system such as the A380 and A340-600 wing assembly projects. 飞机刚性装配在大尺度系统如A380和A340-600机翼装配项目上对飞机制造者来说是非常成功的。INTRODUCTION The Airbus A380 is the largest commercial aircraft to enter production. 空客A380是进入制造领域的最大商业飞机。The size of this new aircraft required Airbus to develop new facilities and new methods to manufacture and assemble its components. 这款新式飞机的尺寸要求空客开发出新的设备和方法来制造和装配它的部件。AirbusUK is responsible for the design and manufacture of the A380 wings.空客英国负责设计和制造A380的机翼。 A new factory was constructed in Broughton, Wales, for the purpose of assembling and equipping the A380 wings. 为了assembling and equipping A380的机翼在Broughton, Wales已经建立了一个一个新的工厂。This new factory and the wings, which leave it, are a shining example of the confluence of cutting-edge aerospace design and state-of-the-art manufacturing technology (Figure 1). 这家新的工厂和它研制的机翼就是前沿航空设计和艺术气息制造技术的完美结合。Most new aircraft programs encounter the challenge of balancing the time required for design optimization with product delivery constraints. 大部分新的飞行器项目面临着平衡设计最优化和交付期限之间的时间的挑战。This issue is further exacerbated by todays demands for shorter and shorter product lead times. 当今对越来越短lead times的要求更加剧了这个问题。Historically, tooling is used to set precision relationships required on large aircraft assemblies such as wings. 历史上，装配是用来保证像机翼这样大型飞机部件准确度的。Typically, in order to maintain the high positional tolerances, detail locators are manually set using precision metrology equipment. 典型的如detail locators为了保持高的位置公差而手动操纵precision metrology equipmentAs a result, tooling requirements have created large hurdles to lead time reduction and product flexibility. 结果装配要求对减少lead time和产品柔性造成了巨大障碍。Figure 1: Airbus UK A380 Factory in Broughton, N.Wales, UK The large size, low relative stiffness and high positional tolerances required for aircraft components drive the requirement for tooling to maintain the precision part relationships over time. 大尺寸、低相对刚度和高位置公差要求的飞机部件要求装配能够长时间保持之间的精密关系。The use of “Determinate Assembly” or the tooling itself can provide the desired flexibility and lead time reduction. 利用“确定性装配”或模具本身可以提供需要的灵活性和交货时间减少。Use of todays advanced 3-Dimensional CAD systems coupled with the high accuracy of CNC machines enables the success of the determinate assembly approach for aircraft tooling. The A380 and A340-600 wing panel systems provide illustrations of how this method supports concurrent aircraft and tooling design. This presented approach provides the aircraft manufacturer significant lead-time reductions while at the same time it results in enhanced system flexibility. 在大型、低相对刚度和高位置公差要求飞机部件驱动要求精密模具维护部分关系。 利用“确定性装配”或模具本身可以提供需要的灵活性和交货时间减少。 使用当今先进的三维CAD系统加上高精度的数控机床使成功的确定方法,为飞机装配工具。 A380和A340 - 600的翼板系统提供的插图的方法支持并行飞机和模具设计经验。 这一方法提供的飞机制造商显著减少交货时间的同时,其结果在强化系统的灵活性。DRIVERS FOR USE OF DETERMINATE ASSEMBLY The world of aerospace manufacturing is becoming more and more aggressive every day. 每一天世界航空制造业都在变得越来越积极。Customers want aircraft, which are more efficient and carry more load than ever before.客户想要飞机，这更有效也比以往任何时候都更有压力。 They expect these aircraft to be right around the corner, not ten years in the making.他们希望这些飞机马上就能做好，而不是用十年。 In order to meet these high standards, aircraft designers have turned to new tools and methods, which allow them to quickly evaluate their designs and readily communicate part geometry to manufacturers. 为了满足这些高的标准，飞机设计师已转向新的工具和方法，使他们能够迅速评估他们的设计并和制造商容易沟通part geometry。The advent of computational tools such as Finite Element Analysis (FEA) and Intelligent Computer Aided Design (ICAD) has accelerated the pace of design optimization and allows refinement of component designs to a level, which was unheard of until recently. (3) 计算机工具的出现如有限元分析（FEA）和智能计算机辅助设计（ICAD）加快了优化设计，使部件设计的完善水平达到一个前所未闻的水准。In order to sell aircraft in todays market, new aircraft programs must hit the ground running. Production ramp up rates must meet new more aggressive targets to satisfy market demands. Typically, precision tooling and assembly equipment are used to set the relationships between and fasten or bond together the myriad of parts, which make up the aircraft frame. In order to enable production rates to rise, it is necessary for the assembly equipment to be ready for production as soon as the aircraft components are ready for assembly. However, major assembly tools are typically larger than the aircraft parts themselves. Since the tooling design is dependent upon the design of the aircraft, tooling manufacture and configuration typically presents a rate-limiting step in new aircraft implementation cycles. Further, as the aircraft designs evolve and variants are introduced, we again find the required tooling modifications on the critical path to delivery. The increasing demand for lead-time reduction requires a new approach to tooling design and implementation. 为出售飞机，在今天的市场上，新飞机计划必须脚踏实地。生产坡道率必须达到新的更积极的目标来满足市场需求。通常，精密模具和装配设备是用来设置之间的关系和固定或结合在一起的各种配件，使飞机框架。为了使生产效率提高，这是大会的必要设备，准备用于生产尽快准备好组装飞机部件。然而，主要装配工具通常大于飞机零件本身。由于模具的设计取决于设计的飞机，模具制造和配置通常提出一个限速步骤，新飞机实施周期。此外，由于飞机设计的演变和变种介绍，我们再次找到所需的工具修改的关键路径的传递。日益增长的需求提前期TECHNICAL BACKGROUND OF DETERMINATE ASSEMBLY To attack this problem, many companies have been evaluating the use of “Determinate Assembly.” Determinate Assembly is a term used to describe the practice of designing parts, which fit together at a predefined interface, and do not require setting gauges or other complex measurements and adjustments. It is part of the more general practice of “Design for Manufacture and Assembly” (DFMA). The potential benefit of determinate assembly is a reduction in tooling, which thereby reduces both cost and lead-time. Conceptually, the component parts are manufactured to a high degree of accuracy, which allow the parts to “snap together” and still maintain their required positional tolerance. Much has been written about the promise of determinate assembly and similar practices (4,5). However, the benefits have yet to be realized on a large scale for production parts such as wings due to the part size and flexibility, thermal issues and the high positional tolerances required. Therefore, assembly fixtures are typically still required. Determinant assembly has however proven itself in the manufacturing processes by greatly simplifying tooling design and manufacture. 攻击这个问题，许多公司已经评价使用“确定装配。”确定装配是一个用来描述设计实践部分，其中组合在一个预定义的接口，而不需要设置压力表或其他复杂的测量与调整。这是部分更一般的实践”的设计制造和装配”（中）。潜在的利益确定装配是减少模具，从而降低成本和交货期。从理论上说，这些零部件制造精度高，使部分“单元”，仍然保持其所需的位置公差。很多人已书面承诺确定装配和类似的做法（4 , 5）。然而，这些好处还没有实现大规模的生产零件如翅膀由于部分大小和灵活性，热问题和较高的位置公差要求。因此，装配楼An initial implementation of determinate assembly in tooling arena came on the A340-600 panel-build cell. This assembly cell is used to locate and fasten aluminum stringers to machined aluminum skin panels (2). These are very large assemblies on the order of a few meter high and over thirty meters long. The original fixtures used to locate the stringers and wing skins followed a conventional design. Individual details for stringer locations were designed and field set using laser trackers. Over two thousand individual points had to be aligned in the field. This was a difficult, labor intensive and time-consuming process. 初步实现确定装配工装上就A340 - 600 panel-build细胞。这种细胞是用来定位和固定铝特约加工铝皮板（2）。这些都是非常大型集会的命令几米的高度超过三十米长。原设备用于定位的特约记者和机翼后，传统的设计。个人的细节设计和领域斯特林格位置设置使用激光跟踪仪。超过二千个人的点是一致的领域。这是一个困难的，劳动密集和费时的过程。Subsequent to the initial production implementation of the A340-600 system, the panel-build fixtures had to support a unique test wing configuration. In order to accommodate this test part, the fixtures had to be altered and the process had to be integrated into an already tight build program. The solution therefore demanded that the alterations resulted in minimal downtime for the one time change and restoration to the original build configuration. To address this requirement, the concept of a “pegboard” formboard was developed. Formboards are used to mount the stringer location indexes. With this approach, high accuracy holes were machined into the formboard. Precision locating dowels were pressed into these holes. This resulted in a series of “pegs” with high positional tolerances. Stringer nests were then manufactured again to a very high tolerance. These nests however were relatively small and can be reliably machined on readily available commodity CNC machines. The stringer nests are then located onto the formboard pegs though precision bushings. The total tolerance stack-up between the sets of parts is less than the required aircraft build tolerance. Figure 2:Determinate Assembly on A340-600 test-panel tooling modifications In the field, only the formboard must be located as opposed to the up to twenty individual details per board. This saves significant field time. Further, the peg locations can be determined early on in the aircraft design process, since the final precision stringer locations are set by the stringer nest. (See Figure 2) This allows the majority of the tooling to be designed and manufactured very early in the wing design program. CONCURRENT BUILD ON A380 The A380 signifies a step change in aircraft size. This wholly new aircraft presented the designers with significant challenges to design a wing, which can handle the required loads and maintain optimal aerodynamic efficiency. As with all new programs, while the aircraft design had many hurdles to overcome, it was imperative that the program milestones be maintained. In order to meet these requirements, a fundamentally new approach to the assembly tooling was required. The tool design and manufacture needed to progress completely in parallel with the aircraft design. The experience of determinate assembly on the A340-600 static-wing test panels provided the foundation for the implementation of this new process. By using the determinant assembly concept, thousands of stringer index points could be incorporated into a couple hundred formboards with “pegs” (locating pins). (See Figure 3) All of the structure, which supported and roughly located these formboards could be designed, built, and installed ahead of the final aircraft-component design release. The formboards themselves could be manufactured from very preliminary aircraft data. Once the aircraft-component data was final-released, only the individual groups of indexes (“index plates”) had to be manufactured. These were then essentially dropped into place on the formboard pegs. Figure 3: Prototype A380 pegboard (“formboard”) and one index-plate While the approach seemed sound, it was by no means an easy solution. The geometry of the aircraft components and their location indexes restricted the amount of flexibility, which could be incorporated with this approach. The sheer size of the A380 panels and the large number of index points meant that any systemic problem with the method carried large risk. Design envelopes and change criteria had to be rigorously negotiated between tooling and aircraft designers. While not overly restricting aircraft component design, tooling requirements were embedded into the aircraft design system (see Figure 4). WING SKIN STRINGER CROSS-SECTION ANGULAR ORIENTATION AGREED-ENVELOPE OVERALL HEIGHT AGREED ENVELOPE STRINGER CENTERLINE Figure 4: Typical envelopes of allowable stringer cross-section changes, agreed between design and tooling This allowed the AirbusUK designers the freedom of making changes within predetermined envelopes without worrying about tooling impact. It allowed the tooling engineers to progress the design and build of nearly all the tooling components, minus the specific indexing components (e.g. index plates) at the onset of the program. For this approach to be successful, it required close communication between the aircraft and tooling engineers. By agreeing on boundaries, which were respected by both sides, each could achieve their goals and meet the aggressive production program. In the wing majors fixture, the use of determinate assembly methods allowed the manufacture and installation of all the major index assembly features significantly ahead of the release of the final wing data. The final data was released approximately one month before first wing load. Index features used to set hinge line geometry were designed and installed using final index flags. The flags were located on the previously installed structure using the determinate assembly features. The optimization of the DA features allowed for a fully integrated concurrent program, reducing the timeline required from engineering concept to release for manufacture. The use of the determinate methods for tooling allows for the quick reconfiguration of the fixture for future A380 aircraft models. The index flags can be replaced for future variant configurations by simply removing the index flag and installing the new index flag. The index flag is simply pinned into the support post and released for production. Figure 5: Initial installation of A380 panel-build posts & formboards on-site at Broughton, N. Wales The approach proved extremely successful. Using the 3D CAD part definitions and the developed tooling definitions, tooling engineers were able to quickly translate the part geometry into indexes, which were final machined to exacting tolerances. Just six weeks after the final design release, the first assembly jigs were fully validated and parts were loaded. Every aircraft component was exactly in the right place. (See Figure 6.) The approach was used throughout the wing assembly system for panel-build and wing majors tooling systems. The elimination of the requirement to field set thousand of index points removed significant time and expense from the A380 wing panel tooling program. Further, this approach provided the aircraft designers with the flexibility to make modifications to the stringer and hinge line geometries very late in the program without driving the critical path to the right. Figure 6: Completed A380 panel-build fixture with stringers partially loaded CONCURRENT BUILD ON A340-600 HIGH GROSS WEIGHT The success of the A380 program has now been extended to other programs. The approach is currently being adapted to an existing program to address changes, which result from the introduction of a variant aircraft. Airbus has recently introduced a new High Gross Weight version of the A340-600. Small changes to the wing structure would under normal conditions require significant tooling changes or even the procurement of all new tooling. For in-jig assembly systems such as the LVER process (1), it could eliminate the ability to use the system for the continued manufacture of both variants. To minimize cost and maximize the usage of existing assembly equipment, it was decided to adapt the existing tooling system to the determinate assembly process. This approach permits the manufacture of the two different variants in the same system with only minor tooling changes. To implement this system, the existing formboards are replaced with the pegboard style formboards. Two sets of stringer indexes adapted to these boards are manufactured for the variant types. To reconfigure from one variant to the next, only the index plates must be changed. This can be accomplished in less than one shift and does not require time-consuming and expensive metrology equipment. Plate clamps are swung out of position; the stringer index is removed from its locating dowels and replaced with the variants index plate. Color codes are used to assist the operators with index type. This provides significant enhancements to tooling flexibility and cycle time reduction. CONCLUSION Determinate assembly for aircraft tooling has been proven for tooling manufacture on both A380 and A340600 wing assembly projects. The dramatic improvement in 3-dimensional CAD modeling capabilities coupled w