Practically defined that friction welding is advisable to apply in the following cases:
- instead of electric-arc and other means of fusion welding;
- Instead of resistance welding;
- instead of soldering and riveting;
- instead of detachable joints details;
- with the manufacture of parts of complex forgings by their separation into simpler blank followed by welding;
- when joining details with final machine-treated surfaces;
- when creating new designs of rational parts that optimally meet the operating conditions;
- for repairing details and tools.
Absence of welding spatter and high accuracy compound allows to apply this friction for welding parts that have passed final machining, including grinding and polishing. Anti-corrosion and strengthening coverings on parts is not an obstacle for welding, because the resulting relatively small heat-affected zone near the junction saves coverage. The same feature of the process makes it possible to weld hardened parts. Friction welding is advisable to apply for restoration of hardened parts, especially metal-cutting end tools. This may be used as for a second-hand parts of items, and newly manufactured parts. When calculating the tool costs using friction welding is generally less than 50% as compared with other methods of recovery also the quality is considerably higher.
The effectiveness of the friction welding depends on the following factors:
• design and technology base case details;
• material of the workpiece and its constituent pieces;
• the size and weight of the items;
• rational choice of design pieces, such as a welded joint and manufacturing parts using friction welding.
Depending on the design of blanks and manufacturing details sources of savings from the use of friction welding are different (see. Table.).
When replacing the butt welding of the main savings result in a reduced labor intensity, reduce the consumption of the base metal and electricity, and in some cases – a significant reduction in losses from marriage welding. While labor input is reduced mainly on preparatory operations (excludes cleaning surfaces of the parts while providing electrical power supply), due to the elimination of heat treatment operations and editing parts after welding. Saving the base metal is achieved due to a significant reduction in allowances for welding, especially expensive high-alloy steels, in some cases by reducing the allowances for machining after welding, which is made possible by improving alignment of parts.
If you are replacing an electric arc welding and brazing eliminates the need for welding materials, reduced consumption of the base metal and tools, and reduced complexity of the loss of electricity. A significant reduction in labor input gives the characteristic friction welding performance improvement process.
In the manufacture of stamped parts basic savings obtained due to the choice of a rational design of the workpieces being joined. Similar economic indicators gives the application of friction welding in production step parts (eg shaft) of the blanks the most appropriate profile hire.
В отдельных случаях при использовании сварки трением получают значительный экономический эффект в результате замены материала части детали. При этом не ухудшаются эксплуатационные характеристики детали и обеспечиваются новые технологические преимущества (улучшение условий для механической и термической обработки и др.).
The effectiveness of the friction welding increases with the size of the program and registration details. Depreciation costs of equipment for friction welding is often higher than in the base-case scenario, because of the high cost of individual and small-scale production of friction welding machines. But even with this payback equipment does not exceed one and a half years.
Table: Examples of friction welding penetration
