![]() ![]() On the other hand, the solid type of wire can be paired with undersized contact tips because the rigid structure leads to fewer problems with feeding the wire through the tip. Tubular and aluminum type wires are known to perform best with either standard or oversized contact tips. There is a +/- 0.002” tolerance for tubular wires. In other words, if the wire in your machine is a 0.045” wire, then you would only be able to operate with a contact tip sized from 0.044-0.046” to be in accordance with AWS code. If your wire is solid, the code states that there is a +/- 0.001” tolerance range for 0.045” wire. The American Welding Society (AWS) Code 5.18 allows some flexibility on the contact tip you can select for a certain type of wire. ![]() If your wire is 0.030 inches in diameter, then you will want to seek out a contact tip, such as this Miller MIG Contact Tip, that is rated 0.030 inches. Size of WireĬontact tip thread size is often expressed in terms of the size of wire that it is compatible with. ![]() You can learn more about why it’s important to select the right contact tip thread size in The Weldermagazine. The size of wire that the particular tip is compatible with.MIG Welding contact tips are selecting according to : Contact tip thread size is reported in both inches and millimeters. Looking at contact tip sizes can be like reading a foreign language if you don’t know what you should be looking for. If you are in a situation where multiple people are using your MIG welding equipment every day, then you might want to avoid potential confusion by rolling with fixed recess contact tips rather than the adjustable ones, as is recommended in Fabricating & Welding magazine. The downside to adjustable recess is that they leave room for error. Adjustable recess contact tips can offer advantages if you are working on a variety of projects. Fixed RecessĬontact tips are manufactured with either an adjustable recess or a fixed recess. The greater the recess value, the longer the wire sticks out at the end of the nozzle. The contact tip recess is a measurement of the position that the contact tip takes within the nozzle. On a MIG Welding Contact Tip sizing chart, you will notice a column that says “Recess/Extension.” Understanding this measurement is crucial for being able to pick out the right contact tip for your work, although it is often an overlooked factor. This can run up your operating costs as you have to replace parts more often than you normally would have to. This can also lead to burnback.Too much heat can also reduce the lifespan of the contact tip. On the opposite end of the spectrum, choosing a contact tip that is oversized for the wire leads to a decrease in the amount of current transferred from the contact tip to the wire.Ĭhoosing an oversized contact tip also leads to an increase in the temperature at the contact tip. This results in evident burnback at the tip, characterized by the formation of a weld inside the contact tip itself. In MIG Welding, increased friction leads to a lack of control over the wire feeding process. In the vast majority of applications, using an undersized contact tip will increase friction. This applies to cases in which you are using a wire fed from a drum weighing 500 pounds or more. In select circumstances, choosing an undersized contact tip can improve the quality of the weld. In the majority of circumstances, choosing a contact tip that is most compatible with the size of the wire will yield the best results. Choose A Contact Tip That Matches The Size Of The Wire Selecting the right contact tip is the difference-maker between laying down a quality weld the first time and having to grind off bad welds to try again. Selecting the correct contact tip for the job is crucial because you want to create optimal conditions in which the wire feeds through the tip with minimal resistance. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |