Resistance Welding Simulation Software


SORPASis dedicated professional software for simulation and optimization of resistance welding processes. It has been specially developed for engineers by engineers. It doesn't need any prior knowledge in numerical simulations, but can be easily learned and used by engineers with knowledge of welding and materials. The integration of welding expertise with numerical techniques has made SORPAS a unique and powerful tool for engineers directly working in industry.


The build-in material database in SORPAS has included nearly all commonly used metal materials including all types of steels, aluminum alloys, titanium alloys, copper alloys, nickel based alloys, surface coating materials, pure metals and high melting metals such as tungsten and molybdenum etc. The users can also add their own materials. It is possible to simulate with dimensions of weld parts ranging from ordinary sizes in millimeters down to micro sizes in a fraction of micron with welding machines of all types of power sources including AC, DC, MFDC, inverter, and capacitor discharge.


* Save costs

* Reduce lead time / time to market

* Speed up production running-in

* Improve weld quality

* Increase production stability

* Facilitate innovation

* Modernize technology

Numerous new inventions have been supported with SORPAS simulations


SORPAS has been applied in various industries for solving problems in spot welding, projection welding, butt welding and micro resistance welding and supporting research and development as well as process parameter optimizations.

Intelligent Weld Planning (Add-on Module)

One of the most exciting new functions released with the new version SORPAS 10 is the Intelligent Weld Planning for predicting the Optimal Weld Schedule (weld current, force, weld and hold time).


According to the user-defined Weld Task Description (WTD) with information of the sheets, electrodes, type of welding machine, and the desired weld quality, SORPAS will automatically optimize and find the optimal weld current, force, weld time and hold time.

The splash (expulsion) limit is predicted. Thereby the welding process window is predicted between the quality required minimum weld nugget size and the splash (expulsion) limit.

The Weld Planning Report will be finally produced with the WTD information of sheets, electrodes and weld machine; the predicted optimal Weld Schedule Specifications (WSS); the welding process window with optimal weld current, force, weld time and hold time; and the Weld Quality Results obtained with the optimal welding process parameters.

The SORPAS Weld Planning works in the following procedure:

• WTD - Weld Task Description

• User Preferences

• Run Weld Planning to predict Optimal Welding Parameters

• Weld Planning Report with WSS - Weld Schedule Specifications


1) WTD - Weld Task Description is to define the weld task with specifications of sheets, electrodes, type of welding machine, and desired weld quality, see the figure to the right.

2) User Preferences is for user preferred planning strategy. The weld current will always be optimized by SORPAS, but users have freedom to choose their own preferred values for the weld force, weld time, or number of pulses by giving a specific input value, or simply leaving the parameter at 0 to let SORPAS fully optimize.

3) Run Weld Planning. After defining the Weld Task and selection of User Preferences, the Weld Planning can be started by simply press the "Start" button. SORPAS will then automatically run all the optimization procedures to first determine the optimal weld force and weld time, then to predict the welding process window and the splash (expulsion) limit, and finally to optimize the weld current and the hold time.

4) Weld Planning Report with WSS - the Optimal Weld Schedule Specifications is the results of the Weld Planning, which includes the given WTD, the predicted optimal welding process parameters (weld current, weld force, weld time and hold time) and the welding process window, as well as the weld quality results predicted with the optimal welding process parameters.

During the Weld Planning, all simulations and optimizations are done with only the same one data file, which substantially reduces the computation time and the use of hard disk space comparing to the generation of Weld Growth Curves and Weldability lobes.