Knowledge Management

Technology watch


A method and a fixture system for positioning and fixing details for assembly

It is a well-known fact that welding companies encounter severe problems, incur costs and lose much valuable time in connection with positioning and clamping operations during welding assembly, all caused by the fact that there are no adjustable fixture systems with surrounding equipment available on the market. This means that such companies suffer from severe problems such as long set-up times, inferior precision, inferior repetitive accuracy, high fixture costs, long door-to-door times with the resulting binding of a great amount of capital, low flexibility, high degree of difficulty in re-setting and problems in connection with recruiting the staff due to the degree of difficulty of the work. The object of the present invention is therefore to provide a method and a fixture system for positioning and clamping details to be assembled, specifically but not exclusively for welding assembly, which provide i.a. optimum flexibility, short set-up times, low fixture costs, high repetitive accuracy and minimum cassation due to high accuracy, and which may be employed for production in long or short series.The present invention relates to a method and a fixture system for providing a fixture for the positioning and clamping of details to be assembled, preferably by welding. According to said method drawing information for the assembled product is provided either in a computer program or as a construction drawing, a zero position on the product is established, an installation plan for the fixture to be built is provided by determining support positions in a system of coordinates, for the fixture relative to the product, based on the drawing information and starting from the zero position on the product and the fixture is built up according to the established installation plan and from standard fixture components (1, 5, 7, 14) selectively interconnectable by means of hole systems (2, 6, 18, 15) extendable along the X-, Y- and/or Z-axes of the coordinate system.


Method and computer program for automated design and manufacture of custom workholding fixtures requiring machining of substantially unique mounting geometries

A method and computer program providing for substantially automated CAD/CAMdesign and manufacture of custom workholding fixtures (22) used to locate and secure workpieces (24) on which work, such as, for example, machining, welding, or assembly, is to be performed, wherein computer models of support structures (26) and locating and clamping devices (28), including dimensions and mounting geometries associated therewith, facilitate development and testing of a workholding concept, production of fixture of a corresponding control program for controlling a CNC or CAM machine for manufacturing the fixture.It is often desirable to create a custom workholding fixture to locate and clamp, hold, or otherwise secure parts, workpieces, or other items on which it is desired to perform manufacturing operations such as, for example, machining, welding, or assembly. Unfortunately, developing such a workholding fixture, from design to actual manufacture, can be a slow, expensive, and generally inefficient process.Presently, fixture creation begins with development of a “workholding concept” or strategy for holding the workpiece during the manufacturing operations. A common method starts with a support or base structure, typically including, for example, a horizontal mounting plate, a tower structure, an angle plate, a window structure, and other support structures. A designer selects and arranges one or more locating and clamping devices in a manner sufficient to adequately and safely locate and secure the workpiece on the support structure. Such selection and arrangement is made with hard-won experience and is based on such considerations as, for example, the specifications and characteristics of the workpiece, the devices, and the support structure; the particular application and operations to be performed on the workpiece; and the particular circumstances surrounding those operations.As will be appreciated by those with skill in the art, development of the workholding concept is a custom process for each different workpiece. There are no set standards, meaning every person engaged in this type of work may do things differently. Thus, with little or no standardization, the process can require considerable knowledge and experience in designing and in developing workholding concepts, and can include substantial risks of costly and time-consuming human errors.


Automatic welding process and fixture to be used in said welding process

The present invention concerns a welding process operated by an automatic equipment and welding fixtures for being used in said welding process.More in detail, the invention concerns a welding process of the aforesaid type and the relative welding fixtures for joining together elements of complex tri-dimensional structures, and more in particular, but not exclusively, for welding together metal tubular elements to form lattices.It is known that automatic welding equipments allow for overcoming some inevitable drawbacks deriving from manually operated welding. In particular, automatic welding equipments allow for overcoming the problem of a production quality which is not constant and is difficult to control, thus assuring an optimal control of the parameters needed for a good welding, with a great reduction of production time and costs.Automatic welding equipments are constituted by an industrial robot, provided with a welding head, on a support arm of the robot, movable in the space along a plurality of coordinated axes. All is controlled by an automatic control unit, where the features of the pieces to be welded are set, in particular their position.In order to assure the correct welding of all pieces, it is therefore fundamental that the welding head can find the pieces to be welded already close to each other and exactly in the position determined and set by the automatic control unit, in other words it os essential that the position of the pieces to be joined together is rigidly grant. To this aim, specific supporting and moving means are used, called welding fixturetables or, more simply, welding fixtures, providing for an housing for the different pieces to be joined together and, therefore, allowing forachieving the approach of the pieces to be welded assuring at the same time the correctness of their position. This kind of method is, at present, the most common, but it presents some limitations anyway, in particular depending from the dimensional complexity of the final product that it is desired to obtain by weldingsuch pieces. For example, this process does not allow to assemble lattices having a square section of the kind commonly used for the realization of modular structures such as for example exposition stands or stages.


System for automated welding of parts assembly in controlled environment

The present invention relates to welding systems, and particularly to a welding system for performing a multiplicity of welds of varying character at multiple sites to join a plurality of parts into a complex assembly on an automated basis.

There are numerous manufacturing applications calling for the welding of a multiplicity of metal parts into a complex assembly of exacting dimensional tolerances and physical integrity. The welding process choice depends in large measure on the metallurgical characteristics of the parts. In some cases, the welds must be performed in a controlled environment ranging from a vacuum to a high positive pressure. When the parts are formed of a particularly reactive metal, welding in an inert gas atmosphere is required to prevent degradation of the part’s physical characteristics. This means that the welding process must be performed in a sealed enclosure or weld box while filled with an appropriate inert gas, such as argon. Thus, each time the weld box is opened to unload a welded assembly and to load a fixtured assembly of loose parts for the next welding operation, considerable time must be spent purging the weld box of reactive gases (air) in order to re-establish the inert gas atmosphere to its requisite integrity. Obviously, this purging step slows the manufacturing process and involves a considerable expenditure of inert gas. If the welding operation has to be interrupted to manually reposition the weld fixture carrying the partially welded parts assembly so as to access other weld sites on the assembly, the purging step must be repeated.

In accordance with one aspect of the invention, there is provided awelding system for uniting a multiplicity of parts into a structurally rigid assemble under a controlled environment. To this end, the weldingsystem includes a multi-axes positioning apparatus for supporting afixture holding the parts in assembled positional relation. The positioning apparatus is computer controlled to variously position the fixtured parts assembly such as to access weld sites on all sides of the assembly in rapid, uninterrupted succession.


Market watch



Simufact Engineering GmbH is an internationally acting software house and service company for complex process simulation in the manufacturing industry. Simufact.welding is a customized software solution for analysis and optimization of welding processes. The use of the simulation software enables to transfer trials into the computer. The central task of Simufact.welding is the examination of welding distortions. Moreover, the analysis of heat affected zones helps the expert to draw conclusions on the properties of welding seams.

It allows the welding expert to operate even without previous knowledge of process simulation due to its intuitive Windows user interface. The user interface is characterized by a precise tree structure of processes and objects to serve as a well-structured display. Regular functions like “drag and drop” which support a fast and reliable model design also feature the user interface. As a matter of course, extensive plausibility control, utilization of predefined libraries as well as assistants for model design and analysis are part of Simufact.welding. Simufact.welding releases the user from time-consuming parameter input as it is necessary for complex analyses.

Overview of functionalities:

  • pre- and post-processing in one GUI
  • no data conversion
  • fast presentation of results
  • result evaluation simultaneous to computation
  • interactive graphical sequence control of robots and clamping tools
  • section views for all result values
  • Weldmonitor (trip to all welding seams in a 2D section)
  • measuring point diagrams for comparison with test welding
  • progress indication of calculations with access to already calculated results during the analysis
  • context support for all input areas
  • interface to RoboCad as well as export interface to robots



GeonX – Virfac Welding Designer


GeonX develops and distributes its integrated software solution Virfac® for simulations of welding (fusion and friction), additive manufacturing, machining, heat treatment, surface treatment, and damage resistance (crack propagation based on the XFEM). GeonX has clients in Europe, Japan, North America, in the aeronautics, automobile, naval, and nuclear sectors. GeonX’s leading aerospace client is the SAFRAN Group (France).

GeonX is the integrator, developer and vendor of the VIRFAC platform for Virtual Manufacturing Virfac Welding Designer is based on a transient numerical modelling of the welding processes. The thermo mechanical modelling allows to accurately predicting the level of residual stresses and distortions at the end of the process. The use of Virfac Welding Designer enables the optimization of the welding process by modifying the clamping system and/or the welding sequence in order to improve the design without having to perform expensive experimental work. Accurate results within a feasible time‐frame can be obtained due to Virfac parallel solver capabilities. Welding trajectories can be defined directly from CAD geometry allowing easy definition of complex and multiple welding paths.



Demmeler Tool Administration

The producer of the software is Demmeler. The principal mask shows all basic functions such as tool list, survey of the storing and retrieving gate and status of the tool places. Sorting options of tool list: (a) by location; (b) by state; (c) by orders. There is integrated control on state-of-the-art Windows basis in order to be easy to operate graphic user interface, high machine availability due to intelligent robot control with system of priorities. Furthermore, tools can be exchanged (individual tools, complete cassettes, carriages) during primary processing time, automatic space-optimised storing, thus high tool density in magazine, damaged tool strategy, sister tool strategy, short chip-to-chip time possible thanks to flexible changing point.


Weldspec™ – Welding Procedure Software for engineers and managers who track and manage welding procedures to ASME IX, EN 288 / EN 15614-1:2008 and AWS D1.1

The producer of the software is TWI. It reduces overheads and enhances efficiency in managing welding procedures and qualifications, saves time and money by ensuring welding procedures comply with latest code rules from ASME IX, EN 288/ISO 15614-1:2008 and AWS D1.1 and QA procedures, cuts costs by creating welding procedures to qualify to the maximum ranges of approval and minimum testing. It allows easier selection of materials by using built-in ASME and AWS base and filler materials databases. Furthermore, automatically creates code compliant Welding Procedure Specifications (WPSs) from Procedure Qualification Records (PQRs).


Welding Coordinator™ – Welding Fabrication Management Software for the full site-wide management and traceability of fabrication information

The producer of the software is also TWI. The software increases efficiency and reduces overheads of managing company-wide fabrication, while minimises costs with instant progress reports identifying bottlenecks in fabrication. It saves time and increases productivity by automatically finding qualified welders and welding procedures, speeds up reporting with documents and easily produces ‘end of manufacturing report’ from automatically generated project data books, weld data sheets, WPSs, PQRs, WPQs and NDE/NDT reports.


iWeldspec is the internet and enterprise enabled versions of TWI’s welding software suite for generating welding procedures (Weldspec™) 

The program utilise web versions of TWI’s desktop software and operate through internet browser. It provides direct access to a welding software system managed from central location cutting software and back-up management costs. Furthermore, it also provides a central, shared data system, enabling the company to share documents and save costs when working from multiple sites.


ROBOSIZER Sizing Software

The producer of the software is Destaco. Robosizer is a web-based software which allows users to size automation products to fit their application parameters. Product categories featured in the Robosizer software include grippers, rotaries, slides, thrusters, lift tables, load limiters, compliance devices, tool changers, machine load and unload, and feed escapements.