Demagnetizing on Location

Magnetics specialist Goudsmit has developed a mobile system that can demagnetize on location. For such situations, the system essentially replaces the tunnel with 100 to 200 meters of cable, wound on a wheeled trolley. The cable is wrapped around the pipe or machine to form a coil, and then the flow of current from the control box demagnetizes the object. Until recently only Goudsmit technicians could operate this unit however this has now been upgraded to include an easy to use touchscreen so that anyone can set it up because it makes all the necessary adjustments itself. Anywhere in the world!

A good example of this system in use was when Goudsmit received a call from a Dutch customer who had delivered pipe material to India intended for an offshore pipeline but unfortunately discovered that the sections were fully magnetized. This made it impossible to weld together. This issue had halted construction completely and caused the project to lose money. The contract laborers could do nothing but wait.

After two days of preparation, Goudsmit sent a service engineer, Ger, to India to help solve the problem. The trip by car, plane and train took 21 hours, but once there he was able to demagnetize all 43 sections of pipe quickly and with little equipment.

Undesired magnetism can result from a number of things, such as magnetic lifting of sheet metal or pipes, magnetic crack detection and even mechanical machining processes such as milling, drilling and grinding. These processes can produce residual magnetism, making the product unusable. In the India project, when the welders tried to work on the pipes the welding arc was repelled. This caused the electrodes to be drawn to the pipe. This made welding impossible.

Ger, the technician, was able to measure the magnetic value of several pipe sections and then wound several meters of cable around the ends of one to form a coil. This removed the magnetism completely and he could then spend the next day and a half performing the same procedure on the remaining 42 pieces of pipe to finish the job.

Undesired magnetism can occur in molds at production companies. These can attract together, causing a halt to production or even damage. Companies that have such problems regularly have their own demagnetization tunnel with a control box. This is an easier way of getting the product demagnetized. When this need arises only occasionally, the object can also be sent to Goudsmit to be demagnetized.

This information has been sourced, reviewed and adapted from materials provided by Goudsmit Magnetics Group.

For more information on this source, please visit Goudsmit Magnetics Group.