What Does an Aircraft Assembler Do?

The aircraft not only has a complex shape, but also has a large number of parts and components (up to more than one million pieces). The internal space is compact, various systems are numerous, coordination relationships are difficult to control, and strict quality requirements result in long assembly and installation cycles. A comprehensive high-tech that is technically difficult and involves many disciplines has long plagued the aircraft manufacturing industry. ^[1]

With the large number of new technologies such as digital design and manufacturing technology and composite material forming in the process of aircraft development, aircraft assembly technology has also undergone revolutionary changes, mainly reflected in the following aspects:

(1) The traditional interchange coordination system uses a simulation method to transfer the size and shape of the aircraft, and uses a mold line template, a standard sample, and a process equipment. Due to the use of three-dimensional digital design and manufacturing technology, including the three-dimensional digital definition of products and tooling, and digital pre-assembly technology, the traditional working methods have undergone a fundamental change. Instead, the size and shape of the aircraft are exchanged in digital quantities. New working methods for the coordination system.

This not only improves the quality of aircraft assembly, but also saves a lot of standard process equipment, greatly reducing the cost of model development and speeding up the development.

(2) Because semi-hard shell or hard shell aircraft use a large number of integral structural components, they are large in size and good in rigidity. In the aircraft assembly, the skeleton can be used as the positioning reference, thereby greatly simplifying the aircraft assembly profile, and even Omitting a large number of external shape boards not only simplifies the production process and equipment, but also opens the working surface, which improves the aircraft assembly efficiency.

(3) The use of computer-aided optical instruments (laser tracker, electronic total station) for aircraft positioning measurement and aircraft assembly work, while speeding up the manufacturing process of assembly tools.

(4) Establish a single product data source, adopt advanced configuration technology and change management methods to achieve effective conversion of engineering BOM (product structure bill of materials), manufacturing BOM, and maintenance of BOM, thereby ensuring consistency in the process of transferring a large amount of data. ^[1]

In short, the design of the assembly frame is to correctly select the product assembly according to the specific structural conditions of the assembly object and the accuracy requirements of the assembly (especially the coordination and interchange requirements between the mating parts and the front and rear assembly processes). Positioning points and positioning methods, types and fixing methods of positioning parts; and rationally determining the structural layout of the frame skeleton, and arranging the overall layout of the frame. To this end, first briefly introduce the current main structural types of assembly frames and their applicable assembly objects. At present, the main structural types of riveting assembly frames can be summarized into the following ten types:

The installation of the profile frame is a process of assembling the manufactured plough frame elements (skeleton, positioning parts, and clamping parts) according to the profile design drawings, adjusting to the required position accuracy requirements, and performing the same setting.

The installation of profile is a very important part in the manufacture of aircraft assembly profile.

The accuracy of aircraft assembly is mainly determined by the manufacturing accuracy and installation accuracy of the profile, and the installation accuracy plays a more important role in ensuring the accuracy of aircraft assembly.

During the assembly of aircraft components, a complete set of assembly frames is used, and the complete set of various assembly frames must be coordinated with each other, so that the installation technology of the assembly frames becomes a precise measurement of large-sized spaces. And positioning expertise. In addition, due to the large number of assembly profiles used in aircraft manufacturing and the long production cycle, the manufacturing and installation of assembly profiles occupies a large proportion in the preparation of aircraft production. The installation of the assembly frame is not only technically difficult, but also has a large workload. It is one of the key technologies for aircraft manufacturing.

In addition to the original method of installing a profile with an ordinary measuring tool for the installation of an aircraft profile, the more commonly used method is to install the profile by an analog quantity, and the second method is to install the profile by a numerical quantity.

The method of installing a profile according to an analog quantity is a method of installing a profile developed earlier in aircraft manufacturing. This method is based on the product drawings and mold lines to first produce a profile template and standard sample that reflects the actual size and shape of the product, and then install the assembly profile according to the profile template and standard sample.

The method of installing the profile frame by numerical value is to measure and determine the precise space of each profile element in the profile design reference system through precise plane and space machinery, optical coordinate measurement and positioning system, and fix the profile frame. installation method. ^[3]