What is the difference between manual and manual, product manager, software and design?

With the continuous development of commercial aircraft, the product cost of Boeing in the original mode is increasing, and the backlog of aircraft is increasing. In the fierce market competition, how can Boeing design and manufacture high-performance aircraft with less cost? Data analysis shows that there is great development potential in the process of product design and manufacturing, and the effective way to save money is to reduce the consumption caused by changes, errors and rework. After the parts are designed, they must go through the processes of process planning, tooling design and manufacturing, manufacturing and assembly. In this process, design accounts for about 15% of the cost, and manufacturing accounts for 85% of the cost. Any design change before the delivery of the part drawing can save 85% of the subsequent production cost.

Case analysis and specific practices

In the past, the traditional design methods were used in aircraft development, and the design team was divided according to professional departments, and the serial development process was adopted. From design to prototype manufacture, it takes more than ten years to 78 years. Boeing Company adopted a brand-new concept of "concurrent product definition" in the development of 767-X. By optimizing the design process, collecting the latest management scheme, improving the design, improving the quality of aircraft production, reducing costs and perfecting the plan, the goal of success within three years from design to test flight was achieved.

Comparison between Boeing concurrent design and traditional development methods

In the development of the new 767-X aircraft, Boeing Company has comprehensively applied CAD/CAM system as a basic design tool, which enables designers to design all three-dimensional drawings of parts on the computer, carry out digital pre-assembly, and get early design feedback, so as to know the integrity, reliability, maintainability, productivity and operability of the design in time. At the same time, digital design documents can be enjoyed by subsequent design departments, so as to get feedback before manufacturing and reduce design changes.

(1) 100% digital product design

CATIA is used to design three-dimensional digital graphics of aircraft parts. Using CATIA system to design aircraft parts, three-dimensional solid models can be designed conveniently, and it is easy to assemble and check interference and fit on the computer, and the characteristics such as weight, balance and stress can be calculated accurately by the computer. Intuitive part drawings are helpful for appearance design and understanding the situation after assembly. In addition, profiles can be easily obtained from entities; Using digital design data to drive CNC machine tools to process parts; Product illustrations can also be established more easily and accurately; The user service group can publish user information using CAD data arrangement technology.

All parts design only forms a unique data set, which is provided to downstream users. According to the special requirements of users, only the data set is modified, not the drawings. Each part data set includes a 3D model and a 2D drawing, and the NC process can be represented by the wireframe and surface of the 3D model.

(2) Pre-assembly of 3D solid digital complete machine

The digital pre-assembly of the whole machine is a process of modeling and simulating assembly on the computer, which is used to check the interference fit. This process is based on design. The pre-assembly of digital complete machine will coordinate the design of parts and systems (including pipeline and circuit layout) and check the installation and disassembly of parts. The application of digital machine preassembly will effectively reduce engineering changes caused by design errors or rework.

With the emergence of a new generation of digital pre-assembly software tools, its functions will include interference fit inspection and the selection of the best accuracy. Digital pre-assembly of the whole machine can help designers eliminate interference before drawing. Designers can search and enter other related design systems to check the design coordination. Other design teams, such as engineering analysis, materials, planning, tooling, user protection, etc. , also involved in the design scope, and provide feedback to designers before sending drawings.

(3) Concurrent product design

Concurrent product design is the study of integration, concurrent design and its related processes (including design, manufacturing, assurance, etc.). Concurrent design requires designers to consider all factors related to the product, including quality, cost, plan, user demand, etc. In order to give full play to the efficiency of concurrent design, we need the support of the following factors:

① Cultivate designers in many ways, rationally allocate design and manufacturing teams, and integrate product design, manufacturing and guarantee processes.

② Using CAD/CAE/CAM to ensure integrated design, collaborative product design, product model sharing and database sharing.

③ Using various analytical tools to optimize the process of product design, manufacture and guarantee.

Table 8- 1 Boeing 767-X Comparison between Development Mode and Traditional Mode

767-x mode

Traditional way

Engineering designer

Design and send drawings on CATIA

Using digital preassembly to design pipelines, lines and cabins.

Adopt digital pre-assembly of the whole machine to ensure compliance with requirements.

Pre-assembly inspection of digital whole machine to solve interference

Explain the product with CATIA

Design and distribute drawings on sulfuric acid paper.

Design on sulfuric acid paper

Use prototype

In the manufacturing process.

Hand-painted with samples

Engineering analyst

Analysis with CATIA

Complete the design load analysis before drawing.

Graph analysis

End of evaluation period

Manufacturing planner

Work in parallel with designers

Design of engineering part tree based on CATIA

Creating Illustration Plan with CATIA

Check important functions and assist in software modification management.

Conventional sequence

Design -900 parts

Establish manufacturing. engineering drawing

not have

mold designer

Work in parallel with designers

Design of tooling parallel drawing with CATIA

Use CATIA to check installation and solve interference problems.

Allow the assembly of parts and tools to ensure that the requirements are met.

Conventional sequence

Design with sulfuric acid paper

Responsible for the production of molds.

Responsible for the production of molds.

Numerical control programmer

Work in parallel with designers

Generating and checking NC process with CATIA

Conventional sequence

Use other systems

User service group

Work in parallel with designers

Design parallel drawings of all ground support equipment with CATIA.

Technology release uses engineering data to release materials.

These components are pre-assembled with ground support equipment to ensure that the requirements are met.

Conventional sequence

Design with sulfuric acid paper

Manual illustration

Generate parts/tools

coordinator

Design and manufacturing team

Various institutions

Integrated product development team

Boeing has accumulated 75 years of development experience in the field of commercial aircraft manufacturing, and successfully launched different types of aircraft such as 707~777. In the development of these models, the organizational model of product development largely determines the product development cycle. The following figure shows the evolution of the organizational model of these models.

The product development team of 777 is divided into IPT by function, such as electronic IPT, mechanical IPT and structural IPT.

IPT, as a new product development organization model, is closely related to the cultural background and social environment of enterprises. Here, we summarize the organizational structure and management mode of foreign IPT as a reference for domestic enterprises to establish IPT when implementing concurrent engineering.

(1) IPT is divided according to the vertical line of product structure, and IPT is the hierarchical relationship according to the composition of product parts.

②IPT members come from various functional departments. They make decisions in the development process on behalf of all links in the product life cycle, and collectively take full responsibility for the products developed by IPT. Compared with the past working methods, the biggest difference is that IPT members get daily work instructions from IPT team leaders, encourage cross-disciplinary information sharing and real-time communication, and cancel the commonly used grading approval system.

(3) ③IPT team leaders define product development plans, activities, roles, resources, etc. From the general task. Relatively independent tasks are still completed by functional departments alone.

④ The functional department is responsible for assigning corresponding personnel to undertake tasks according to the task roles defined by the IPT person in charge, and configuring the necessary working environment for the personnel undertaking tasks. A role can be assumed by many people as a group, and one person can also assume multiple roles.

⑤IPT team leader and functional department heads determine the performance of IPT members from task execution and daily work performance respectively. Because functional departments provide personnel and working conditions, they must get financial support from IPT management department.

⑥IPT itself and the characters in IPT have a life cycle. After the product development task is completed, they still return to the functional department. The working mode of IPT needs the support of computer and network environment.

IPT includes various professional technicians who play a coordinating role in product design. IPT members participate in the manufacturing process as early as possible to minimize changes, errors and rework.

Improve product development process

Why did Boeing adopt CAD/CAM system in the past ten years, but it didn't obviously speed up the progress, reduce the cost and improve the quality? The reason is that its development process and management still remain at the original level. The application of CAD/CAM system can effectively reduce the number of changes and design rework, greatly accelerate the design process, and bring benefits far greater than the direct benefits brought by reducing changes and rework. Boeing 767-X adopts fully digital product design. Before designing and drawing, it designs the three-dimensional models of all parts of 767-X, and completes the digital pre-assembly of all parts, fixtures and components before drawing. At the same time, other computer-aided systems are adopted, such as IDM system for managing parts data sets and drawings, WIRS system for circuit diagram design, integrated process planning system and all downstream drawings and bill of materials data management systems. Due to the adoption of some advanced computer-aided means, Boeing Company improved the corresponding product development process during the development of the 767-X, such as analyzing the system design before drawing, establishing a three-dimensional part model on CATIA, carrying out digital pre-assembly, checking interference and cooperation, increasing the number of feedback in the design process and reducing the big rework between design and manufacturing.

Several major design processes are described below.

(1) engineering design and development process

The process of design and development begins with the establishment of three-dimensional model, which is an iterative process. Designers use digital pre-assembly to check the three-dimensional model and improve the design until all parts meet the requirements. Finally, the model of part drawing, assembly drawing and assembly drawing is established, and the parallel drawing is completed by 2D drawing. The design and development process needs the coordination of design and manufacturing teams.

(2) Digitize the pre-assembly process of the whole machine.

Digital pre-assembly uses CAD/CAM system to carry out assembly simulation and interference check on the three-dimensional aircraft part model, determine the spatial position of the part, and establish a temporary assembly drawing as needed. As a supplement to the digital pre-assembly process, designers get feedback from engineering analysis, testing and manufacturing. The data management of digital pre-assembly model is a huge and arduous task, which requires a special digital pre-assembly management team to ensure that all users can easily enter and make the final inspection before sending the drawings.

(3) digital sample design process

767-X adopts CAD/CAM system for digital pre-assembly, and the digital sample design process is responsible for each part design and sample installation inspection.

(4) regional design

Area design is a comprehensive design process of aircraft area parts, and various models of aircraft area are designed by digital pre-assembly process. Regional design includes not only interference inspection of parts, but also clearance, compatibility of parts, packaging, aesthetics of system layout, support, important characteristics and design coordination. Each design team or design and manufacturing team member is responsible for regional design, and all engineers, designers, planners and fixture designers should participate in regional design. Regional design is the task of each member of the design team or the design and manufacturing team, and its completion requires the joint efforts of the design team, the structural room and the design and manufacturing team.

(5) Design and manufacturing process

The design and manufacturing team is composed of technicians from various disciplines, which plays a coordinating role in product design and minimizes changes, errors and rework.

(6) Comprehensive design inspection process

The comprehensive design checking process is used to check the correctness of the analysis, part tree, fixture and NC surface of all designed parts. The comprehensive design inspection process involves the design and manufacturing team and related quality control, materials, customer service and subcontractors, and is generally carried out in the drawing stage. Relevant personnel regularly check the situation, and put forward suggestions for modification of unreasonable places. Comprehensive design inspection is part of the task of design and manufacturing team.

(7) Comprehensive planning management process

Integrated planning management is a process of improving communication speed, making manufacturing process plan, testing and aircraft delivery plan. The integrated planning management process not only formulates some special process plans, but also synthesizes various plans in the whole development process. Integrated plan management will improve the visibility of the overall plan.

Use digital methods and tools such as DPA to find various downstream problems as early as possible in the early stage of design.

Digital complete machine preassembly (DPA) is a computer-simulated assembly process, which is based on the requirements of designers, analysts, planners and tooling designers, and uses all levels of parts models to preassemble. Check the interference, fit and design coordination of parts in the form of 3D entities. Using the pre-assembly process of the whole machine, all the interference of the whole machine can be found out and solved reasonably. There are 46 sections about 1000 parts between 1600 ~ 1720 stations of Boeing 757, which need to be accommodated in 12 CATIA model for digital pre-assembly.

Using digital pre-assembly process, engineering design should verify that all designs are free to interfere and well matched, which makes the process rarely change. The dataset cannot be drawn without final approval. This final inspection reduces the risk and ensures that no parts interfere after drawing.

The digital pre-assembly of the whole machine is a process of modeling and simulating assembly on the computer, which is used to check the interference fit. This process is based on design. The application of digital machine preassembly will effectively reduce engineering changes caused by design errors or rework. With the emergence of a new generation of digital pre-assembly software tools, its functions will include interference fit inspection and the selection of the best accuracy. Digital pre-assembly of the whole machine can help designers eliminate interference before drawing. Designers can search and enter other related design systems to check the design coordination. Other design teams, such as engineering analysis, materials, planning, tooling, user protection, etc. , also involved in the design scope, and provide feedback to designers before sending drawings. The pre-assembly of digital complete machine will coordinate the design of parts and systems (including pipeline and circuit layout) and check the installation and disassembly of parts.

A large number of CAD/CAM/CAE technologies are applied to realize the production without drawings.

(1) Adopt 100% digital technology to design aircraft parts.

The digital design of aircraft parts adopts CATIA to design the three-dimensional graphics of the parts. Using this system, aircraft parts can be easily designed into three-dimensional solid models, and can be easily assembled on the computer to check interference and fit, and the weight, balance, stress and other characteristics can be accurately calculated by the computer. Intuitive part drawings are helpful for appearance design and understanding the situation after assembly. In addition, profiles can be easily obtained from entities; Using digital design data to drive CNC machine tools to process parts; Product illustrations can also be established more easily and accurately; The user service group can publish user information using CAD data arrangement technology. All parts in 767-X are designed by digital technology, and all parts are designed to form a unique data set for downstream users.

(2) The aircraft design parts library and standard parts library are established.

Minimizing the design of new parts can greatly save money. Based on this understanding, a large number of parts libraries have been established in the development of 767-X, including terminals, angles, brackets and so on. Parts library is stored in CATIA system and coordinated with standard parts library, so designers can easily find parts library. Making full use of the existing parts library resources can effectively reduce the costs of parts design, process planning, tooling design, CNC machining procedures and so on. Standard parts library includes fasteners, washers, connectors, washers, bearings, pipe fittings, pressure plates, etc. These standard parts are stored in CATIA standard library. Designers can directly select the required parts from the standard parts library.

(3) Using CAE tools to analyze the engineering characteristics.

Stress analysis: technicians directly use 3D digital part model to calculate design stress, load data analysis and component safety system calculation.

Weight analysis: By using the 3D digital part model for weight analysis, the analyst can obtain accurate parts weight, center of gravity, volume and moment of inertia. When the digital model of the whole machine is assembled, the analyst can track the assembly of the weight and center of gravity of each component.

Maintainability analysis: Designers should also consider the space requirements for aircraft structure and system during aircraft maintenance, and design corresponding maintenance covers to ensure smooth maintenance. This step is completed in digital design.

Noise control project: aircraft shape identification and noise data analysis are carried out by using aircraft shape details, and the results are passed to relevant designers. This process is completed by using the computer tool Apollo workstation.

(4) Computer aided manufacturing engineering and numerical control programming.

Computer-aided manufacturing process can improve engineering design by providing productivity input and adding additional information to database, thus meeting the requirements of assembly and assembly. Before the engineering drawing is issued, CNC programmers use CATIA tools to program the wireframe and surface of the parts, and if necessary, simulate the CNC machining process on the computer, thus reducing design changes, scrapping and rework and shortening the development process.

(5) Computer Aided Tooling Design

The fixture designer uses the 3D part model provided by the designer to design a 3D solid model or a 2D standard fixture to ensure the part benchmark, and the computer system will store fixture positioning data. At the same time, the digital pre-assembly system of tooling is established, and the interference and cooperation between parts-tooling and tooling-tooling are simulated and tested by using three-dimensional digital data sets. Tool data sets are provided to downstream users, such as tool planning for tool classification and manufacturing planning, NC tool program for NC data sets, NC certification or production in workshops.

Auxiliary concurrent design of product data management system supported by supercomputer

In order to give full play to the efficiency of concurrent design and support the design and manufacturing team to carry out integrated product design, we need the support of a product data management system covering the whole functional department to ensure the collaborative product design process and enjoy the product model and database.

767-X adopts a large-scale comprehensive database management system, which is used to store and provide configuration control, control all kinds of engineering, manufacturing and tooling data, as well as graphic data, drawing information, data attributes, product relations and electronic text retrieval, and comprehensively control the received data.

Management control includes product development, design, planning, parts manufacturing, assembly, final assembly, testing and delivery. It ensures that the correct product graphic data and description content are sent to users. Through the product data management system, digital data can be shared, and data can be dedicated, shared, drawn and controlled.

The traditional drawing distribution method is to transfer the part drawings containing many drawings and bills of materials from the engineering design department to the manufacturing department. Each drawing contains one or more parts and has a unique drawing number, and each part in the drawing also has a corresponding drawing number. Each model of digital product design has a complete part number, so that the graphics can be tracked and checked when they are issued.

benefit analysis

The effective application of concurrent design technology will bring the following benefits:

① Improve the design quality and greatly reduce the design changes at the initial stage of production;

(2) Shorten the product development cycle. Compared with conventional product design, concurrent design obviously speeds up the design process;

(3) reducing the manufacturing cost;

④ Optimize the design process to reduce the scrap rate and rework rate.