Cross Wire Welding
Have you ever wondered how those welded wire mesh products such as fencing, shopping carts, toaster guides, and wire mesh for reinforcing concrete are made?
They all use a technique known as cross wire welding.
It’s a really common process that is used in many other products as well. Below is a comparison between our 10% weld penetration and other companies.
You might be familiar with spot welding, which is heavily used in joining automotive sheet body parts together, but cross wire welding is different.
Cross wire welding is a type of projection welding that offers advantages such as:
- Precision control in rapid mass production
- Welding heavier materials that can’t be spot welded
- Lower electrode efficiency and maintenance
How does it work?
Projection welding involves heating the area as it collapses under pressure. This type of welding is particularly useful for welding different thicknesses of metal together.
In this process the size and shape of the projection (intersection between the two metal sections) is critical, as is the speed of the movement of the cylinder applying the pressure.
If the metal of the projection collapses too quickly before the resistance melting occurs then a strong weld (nugget) will not form. This may also occur if the heat is diffused over too large an area.
If there is too much heat generated before the projection collapses, or if the cylinder is moving too slowly to follow the collapse, then the weld will also not form properly.
Thus, it is imperative that the electrode force is maintained at the appropriate level during the collapse of the projection.
Protective: bringing innovation to cross wire welding
After 30 years of development and technical innovation, mesh welding machines are now capable of consistent precision crosswire welding in mass production settings across multiple wire thicknesses.
Computers now control and automate loading, feeding, straightening, cutting-to length, and pay-off for accurate and efficient production lines.
Rods and wires can be welded in almost any arrangement thanks to computer software that ensures precise, reproducible control of the current, time, and welding force.
Protective Fencing uses the latest technology to ensure that our welded mesh products are manufactured to consistently high standards. So what kind of technology makes Protective cross wire mesh products stand out?
For starters, many other companies still use series weld machines whereas Protective uses highly sophisticated direct weld technology that takes cross wire welding to new levels. So what’s the difference?
Series Welding
Series welding machines are often used for making storage meshes. A series welding machine has a simple construction with an open mesh plane that allows the feeding of the cross rod or wire in or toward the production direction.
Series welding or one-sided welding has limitations as to how the longitudinal bars are divided as well as operation speed and efficiency.
How does Series Welding work?
In this case, both electric poles are on the same side of the mesh. Usually, two welds per current flow are made. This method tends to melt material at the electrode contact area of the longitudinal
rod as a result of the systematic bypass of the welding current along the transverse bar of the last weld – see the arrows in the above image.
Naturally, the amount and rate of the bypass current depends on the rod diameter and the position of the next transverse rod.
This method needs to use a higher total current to compensate for the losses in the bypass current.
Thus, the power requirements for the series welding machine become critical and a limiting variable.
Direct Welding
Direct welding machines offer a degree of flexibility and control that greatly surpasses standard series weld machines.
Direct welding machines consist of an almost unlimited number of floating, independent welding assemblies. Each welding assembly is a self-sufficient system consisting of a transformer, welding press, and power supply.
This independently floating system allows for different diameters of longitudinal rods to be welded quickly and accurately, even where there are tiny and variable distances between cross wires or rods.
Although, such machines are more expensive, they are capable of producing a wider range of manufactured parts. Adjustments in longitudinal bar division and mesh size can even occur during production.
Protective Fencing has three welded mesh machines that use the direct welding method; our expert operators have decades of experience producing high quality products.
Better Weld Penetration: better products
How far the weld penetrates under each rod is a major factor in determining the strength of the weld. Typically, welds with penetration of less than 5% can be easily broken even by hand.
Most fencing applications require a weld penetration of 10% to ensure the strength and integrity of the mesh.
We go even further. In fact, Protective’s Welded Mesh machines frequently produce mesh for strata control in mines which require weld penetration levels greater than 15%.
Our mesh has been independently tested by a NATA certified laboratory and exceeds the requirements specified in clause 7.43.4.1 of AS2423:2002 and clause 6.5 of EN 10223-4:1998 for weld strength.
Protective measures every weld on every sheet of mesh during production to ensure quality.
That’s why Protective Fencing stands behind its products and offers a 10 year warranty against faulty workmanship or materials. Protective fencing; using technology and innovation for products that last.
Source:
Cross Wire Welding – The Other Resistance Process