Welding weave pattern

Thanks, Bill

The decision to weave or use stringer beads is based on the type of metal and the type of joint. Stringer beads are recommended for root passes on steel as an example. Stringers are also the rule for hardfacing using the SMAW process. You are generally better off using one wide bead rather than several narrow ones when joining.

Also, remember that 7018 is called Lo-Hi because of the Hydrogen content, these rods must be kept dry. Either sealed in their factory container or heated well above ambient (most codes call for 350F for at least 4 hours, and you probably know not to use your kitchen oven)

You can make a rod oven the size of 4, 50lb rod containers, out of sheet metal, line with 1" insulation fiberglass board, and use a 100w light bulb as a heater with a thermostat. Made many of them when I worked for the cheap contractors.

T_Bone

T_Bone

My first certified welding test out of 36 tests was a open root 1" plate test with 7018 all the way, yes thats correct 7018 open root. The cover pass was spec'd stringer bead but perfered was a weave, so another words no weave, no pass.

My 2nd Certified welding test was a 6G pipe test, pipe weld at a 45 degree angle with a 6" restrictor ring within 1" of the edge of weld and top side of the weld, sch40, 7018, open root but root could be 6010, preferd weave as a cover pass.

My 3rd Certified test was a Tig, 10" sch:10 SS beer pipe, 5G, "one pass" with 100% penatration with the inside bead appearing the same as the outside bead with a maxmium of 1/2" of a smaller inside bead as long as it was 100% penatration.

I thought these tests would be of interest since they sure was not an common certified welding tests!

T_Bone

I did however use a piece of glove leather attached to my hood neck just because it looked great on the other guys hood but then found out what it was really for when I broke my hood and had to use one without it.

Ahh! Good times! Sure do miss them now.

T_Bone

T_Bone

The CWI certification test is and was a real PITA to pass taking 8hrs to complete that covered all all welding procedures, weld testing (x-ray, magparticle, dye penterant, ultrasonic) and the entire D1.1 code book. For an example at the time I took my test there was approx. 500 CWI's and three Boeing welding engineers in my test class that failed with me passing by 3 questions on 1/3 of the test. I felt very fortunate that I did pass.

As to your questions on the weave pass, a weave can be put in on any weldment by a welder with only the restriction of no more than 8 times the rod diameter for a weave pass. During welder certification tests I would inspect the root pass and the cover pass and nothing inbetween as that was tested after through Nondestructive testing (NDT, ie; x-ray etc) or a bend test. The cover and root pass was inspected for undercutting or any other abnormal condition, another words the "look" fail.

However there is a advantage to the welder to pass a weld certification test using nothing but stringer beads.

T_Bone

The most impressive test I ever saw was a pipefitter taking a 1/2" plate, 7018, root backer, weld test. This guy did the vertical in ONE pass and the plate was dull cherry red when he was finished. The cover was perfect if I ever saw perfect. He did a zig-zag weave all the way up. I always thought I welded hot until I seen this one. And he was pushing retirement age.

T_Bone