RMD on Carbon Steel Pipe 

Hello Stephen! Thank you for reaching out. According to section 6 of the operation manual, the arc length is the distance from end of wire electrode to the workpiece. This term is also used to represent arc length adjustments in RMD and Pulse processes. Increasing Arc Length increases the actual arc length; likewise, decreasing Arc Length shortens actual arc length. We recommend leaving it at 0 as there usually is no reason to change it. Let us know if you have any additional questions.

To my understanding the arc length is a function of the voltage and wirefeed speed. A longer arc length has a greater voltage for a given WFS, and typically will produce a weld with less spatter, greater heat input, and more penetration, greater chance for burn through or dripping. In my application we had to limit arclength to avoid overheating the parts and causing excessive stresses in the parts.

Hi Shawn, thanks for reaching out. What welder were you discussing with the rep? What is your application?

Miller Welders it's the pipeworx 400 and we're rolling out pipe size is 3/4" up too 24" pipe

jaime coronado The following settings are where we typically start our customers with: Wire Feed Speed: 200, Arc Length: 0.0, Arc Control: 0, Gas: 90/10 Ar/C02. Use these settings as a starting point and go up or down to fit your comfort zone. Please let us know if you have any further questions.

+jaime coronado bot this application i thought 15 at 19 volts should be better

@@MillerWelders Hi, we are in offshore pipeline progress by using RMD/Pulse with Gas 80%Ar - 20% Co2. currently we are using the parameter WFS : 200, Arch Length : 0.6, Arc Control : 0. mostly defect on top location i.e 10 o'clock up to 2 o'clock position with defect Lack of root Fusion ore Lack of fusion by NDT exam PAUT. Can you please advise, does parameter that we are using is correct or no? some on 5 - 6 o'clock position always convexity instead of flat position.

This video was developed to illustrate a weld and the specific welding techniques and weld settings used are not necessarily the best for all applications. The Specification Sheet from the manufacturer of the filler metal you use is the best tool to determine starting welding parameters. We intentionally left the weld settings out of this video because following any local, state, or national codes or standards is the responsibility of the welding organization producing the weldment. Testing the weldment will ensure that the settings, technique, and overall procedure that you develop will meet the requirements of any applicable codes or standards. If you have any further questions, please let us know.

Thanks for reaching out. The RMD process featured in this video is a MIG-only process. In general, you can use TIG for a root pass.

Probly for the shielding gas to start flowing before the arc is initiated. Just my best guess

its a preflow setting, if you hold the purge button and spin the trim knob at the same time it will let you enter a menu adn adjust the pre and post flow purge times.

@@Michael-mz8ow fuckin stellar!!!

Great question, Chris! We would recommend using only a stainless steel wire with a high silicon content, such as a 316LSi or 308LSi . Higher silicon content helps the puddle wet out and acts as a deoxidizer. For optimum performance, use a “Tri-H” gas that’s 90 percent helium, 7.5 percent argon and 2.5 percent CO2. Alternatively, use 98 percent argon and 2 percent CO2. We also recommend taking a look at this article as it further discusses RMD: www.millerwelds.com/resources/article-library/new-regulated-metal-deposition-rmd-mig-welding-process-improves-stainless-steel-pipe-fabrication. Please let us know if you have any additional questions and we can happily assist. Thank you!

@@MillerWelders Thanks for getting back to me. This is one of the reasons I have stuck with Miller. I am 62 and the companies that I have worked for in the past would have issues Miller would send reps to the company to help fix the problems. Thanks for not throwing your customers under the bus so to speak.

jimmy holden yes you use gas dude for RMD root, the pulse Mig and the dual shield flux fill and cap