1. What are the main benefits of using cold welding?
2. What kind of materials can be welded using cold pressure?
3. How can pressure create a weld?
4. Can different metals be welded using cold pressure?
5. Why can’t ferrous materials be welded using cold pressure?
6. Is a cold pressure welder difficult to operate?
7. What about maintenance costs?
8. I need to join fine wire. Can this be achieved with cold pressure welding?
9. Can I join copper rod sections without using large quantities of power?
10. Can I weld two wires that are different in size?
11. How much difference in size can there be between the two wires?
12. What is the tolerance of die to wire?
1. What are the main benefits of using cold welding?
The process is quick, reliable and cost-effective. The weld cycle takes only seconds to complete and creates a permanent bond stronger than the parent material, without using heat, fillers or fluxes. No set up is required and many PWM machines incorporate a system for automatic removal of the worst of the weld burr on completion. PWM cold welders are extremely easy to use (so there is little or no need for operator training) and inexpensive to maintain.
2. What kind of materials can be welded using cold pressure?
Cold welding can be used to join most non-ferrous wire and strip with diameters of between 0.08mm (.003145") and 25mm (.984") copper and 30mm (1.181") aluminium. Various aluminium alloys, 70/30 brass, zinc, silver and silver alloys, nickel, gold and many other materials can also be welded using cold pressure.
3. How can pressure create a weld?
The cold pressure welding technique employs a ‘multi upset’ principle, perfected by a British company, GEC. Each time the cold welder is activated, the material that is inserted in the die is gripped by the die and fed forward. As the two opposing faces are pushed against each other, they are both stretched and enlarged over their entire surface area. The oxide and other surface impurities are forced outward from the core of the material and a bond is created. A minimum of four ‘upsets’ is recommended to ensure all impurities are squeezed out of the interfaces.
4. Can different metals be welded using cold pressure?
Cold welding can be used to join dissimilar materials, such as aluminium to copper. For example, transformer manufacturers have used PWM machines to weld copper rod terminations onto the end of the aluminium winding.
5. Why can’t ferrous materials be welded using cold pressure?
Materials which contain carbon cannot be joined by cold pressure welding. Carbon interferes with the flow of the material and stops the cold weld process taking place. (Trials have been carried out on low carbon steel wire, but even with this material, heat had to be introduced into the wire in order to lower its tensile strength and cause the material to flow together during the cold weld process.) There are cost and safety implications involved in incorporating a heating facility to a cold pressure welder, so it is more practical and cost-effective to use hot welding to join ferrous materials.
6. Is a cold pressure welder difficult to operate?
Our machines are all extremely easy to operate. Most people require little or no training to use a PWM machine. Even our largest models, the EP500 and the P1500 rod welders, only require the operator to load the material and press a button in order to create a reliable weld every time.
7. What about maintenance costs?
PWM machines are extremely inexpensive to maintain due to the small number of moving parts. If you do have a problem, our network of experienced international agents can provide you with expert on-site advice and support. This email address is being protected from spambots. You need JavaScript enabled to view it. for details of your nearest agent.
8. I need to join fine wire. Can this be achieved with cold pressure welding?
Our M10 Superfine model will weld non-ferrous wire as fine as 0.08mm (.003145"). Although basically the same machine as the standard M10, this machine is made to even tighter tolerances and it is recommended that it be kept purely for the welding of ultra fine wires.
Our hand-held M10 machine will weld non-ferrous wire from 0.10mm to 0.50mm (.0039" to .0196"). The bench-mounted BM10 has a capacity of 0.10mm to 0.60mm (.0039" to .0236").
9. Can I join copper rod sections without using large quantities of power?
Our P1500 rod welder, which has a capacity of 15mm to 25mm (.590" to .984") copper and 15mm to 30mm (.590" to 1.181") aluminium is extremely economical to use, since it only requires an 11KW power supply, and the weld cycle takes only minutes to complete.
10. Can I weld two wires that are different in size?
Yes. Dies can be manufactured to weld two different wire sizes together.
11. How much difference in size can there be between the two wires?
As a general rule, the larger sized wire must not be more than 30% larger than the smaller sized wire. However, each application is different, so for more details, please contact us at This email address is being protected from spambots. You need JavaScript enabled to view it.
12. What is the tolerance of die to wire?
-1% + 3% wire to die tolerance.
If you have any other queries about cold pressure welding, please call us on +44 (0) 1233 820847, fax us on +44 (0) 1233 820591 or email us at This email address is being protected from spambots. You need JavaScript enabled to view it.