How does projection welding work

In most applications, many small projections are made on one surface of the parts to be welded. These projections may be round dimples, elongated ridges, rounded or elongated corners of weld nuts. Two round wires held together at 90 degrees make a point contact. It will also be a projection weld. When the mating part is brought together, these projections concentrate the current flow and generate heat in these locations. When the projections heat up, they collapse as weld nuggets. The result is several weld nuggets holding together after cooling.

There is, of course, one weld per crossing location in the case of cross wire welding, but usually, many are welded at the same time as the fence. Projection resistance is a type of welding. It is named because different projections are formed on the workpieces for effective welding. In this welding process, the designs or shape of the part is used to make the discrete individual contacts to center the current during the welding process.

In most cases, many small projections are formed on the surface of the parts to be welded. These projections may be round dimples, elongated ridges, dome types, circular or elongated corners of weld nuts. Two wires held together at 90 degrees form a contact point contact. When the projection is heated, they collapse, and the weld nuggets are formed at the site of the projections. After the cooling process, several weld pieces are formed that hold the two workpieces together.

Projection weldings are another variation of spot welding. This is similar to spot welding but requires much less current than spot welding. Unlike spot welding, electrodes are not used for heat concentration in projection welding; instead, projection is used on the workpiece for this purpose.

Other factors must be considered, such as alignment, projection consistency, welder follow up and nut welding thread protection while performing the projection welding process. The projection shows welding. No, you can use the projections of any shape. The only precaution that you must take during the selection of the projections is that they must be able to concentrate the heat to form the required weld.

The most used types of projection shapes are button-type projections, cone type projections and spherical type projections. Button type projections are used for the metal sheets having higher thickness. This thickness varies in the range of the 24 to 13 gauge while the cone type projections are used for 12 to 5-gauge metal workpieces. And if you have metal sheets of more thickness than the earlier mentioned then, spherical type projection is used. Following are characteristic of the projection welding that you must know:.

Now, it is the time to know about the advantages. As Projection welding is mostly used for the mass production. It has many applications such as:. So, this is the exact working principle as well as advantages ,disadvantages and applications of the projection welding.

We are sure that you get exact details of the projection welding. After cooling the result is several weld nuggets holding the part together. Of course in the case of cross wire welding there is one weld per crossing location but normally many are welded at the same time as in fencing. The circular ring projection on the bottom of a hydraulic fitting could make a tight hydraulic seal.

The cross wire weld could be fencing or rebar in a roadway. The weld nut holds the various parts bolted on your automobile. The process is the same as a spot weld but in this case the electrode is not used to concentrate the heat. The part projection or arrangement does this.

Multiple welds can be made at the same time when multiple projections are present. It is a very efficient process and not as electrode dependent as spot welding. Other factors must be controlled such as alignment, projection consistency, welder follow up and with nut welding thread protection. Projection welds and processes are designed and developed to fit the various applications.