Preheating is a necessary evil. Equipment like Miller’s ProHeat 35 make it painless by using localized heat for pre- and post-weld heating.
Preheating is a necessary evil. It is needed to slow the cooling rate of a weldment, but the conventional process to do so can be dangerous, inefficient, hot, and time consuming. Historically, preheating has been accomplished with a torch – a slow practice prone to injury. With induction heating, though, welders can sidestep risks and inefficiencies. Equipment like Miller’s ProHeat 35 does just that, creating localized heat during pre- and post-weld heating.
What is induction heating?
Welders use induction heating to electromagnetically stimulate warmth. For example, the ProHeat 35 uses coils that wrap around a base material to energize its molecules, which creates heat. The progression is quick, taking only minutes to reach a desired temperature and keeping it there.
Before induction heating, conventional practices required an open flame. As you can imagine, that opens up the possibility for accidents. All it takes is a distracted operator or a flashback to spur a mishap.
Plus, open flames produce subpar results. An operator using a torch cannot evenly distribute heat onto a workpiece, cannot control if the flame actually goes into the part or determine how much of the flame reflects off the workpiece. In our experience, a torch disperses a majority of the heat away from the weld, making it counterproductive.
The top advantages of induction heating
The rapid electromagnetic process quickly brings materials to temperature. The touch of a button automates the standard, more traditional process by allowing welders to focus more on what they do best: welding. Induction heating systems are simple to operate and take seconds to accomplish what is typically a tedious task. With the ProHeat 35, we found the coils and blanket to move easily around many types of surfaces like pipes and flat plates.
It uniformly distributes heat
Gone are the days of a cracked weld because of a spotty pre-weld heat temperature. The induction process works so well because the heat is focused and not lost to the atmosphere. Induction systems give operators more control over the output of energy. Plus, the ProHeat 35 includes an option to add a reporting system to generate data on joint temperatures.
No flame equals less risk. The absence of an open flame means no explosions, fires or burns. The workpiece is the only hot surface – it heats from within. The equipment and its coils do not get hot, which minimizes the risk of injury.
Our thoughts on the Miller ProHeat 35
This video from Miller further explains the full capabilities of the ProHeat 35 induction system. As you’ll see from the video, the machine has many applications – all more safe, more consistent, and more economical than flame heating.
Our team has used the machine and found it simple to navigate. In our shop, we have it set up on 24-inch 160 carbon steel pipe and we’re able to go from ambient temperature to 350°F in less than 3 minutes.
Luckily, we partnered with Miller to house the ProHeat 35 as a demo machine for fabricators to test out firsthand. We’re proud to be the only welding distributor in the nation with that capability. If you’re looking to address concerns associated with traditional heating methods, we highly recommend this system.
Test the Miller Pro Heat 35 before you buy it for your fabrication shop
Editor’s Note: This is a series spotlighting fabrication equipment found in the Red Ball Oxygen Welding Lab.