Glad you're liking the pipe welding! It's more involved than you'd think. One of the papers here had a picture of a 1.7 million pound vessel being hauled up to the oilsands by Mammoet. There's some serious welding for something that big! It was about 40 tall laying on the trailer and I forget how long but it had a lot of wheels under it and several trucks to move it.
The best way to avoid high wear is to hardface parts when they're new. 7018 can work as a buttering layer but is still soft and will mushroom. They do make what are called build up rods that are harder than 7018 but not as hard as hardfacing that don't mushroom. They can be deposited in multiple layers too. There are many different types of hardfacing alloys. The first thing to figure out is what type of wear you'll encounter, abrasion, impact, heat or a combination. Higher alloy hardfacing will cross check which it's supposed to do to relieve stress in the hard material. It looks like a bunch of cracks across the bead. We have a customer that is using Stoody Vancar wire that's about $35/lb. and comes in 50 lb. spools. $1750 for one roll of wire! It a very good idea to wear a welding fume respirator when hardfacing because there are some of nastiest materials used in hardfacing. Chromium being one of them that is a known carcinogen.
I worked in a shop that did chromium carbide overlay on pipe using mostly automatic equipment. The wire came in 500 lb drums and they'd get about 15 drums delivered at a time. Those drums of wire cost about $150,000 if I remember right. The pipe was used for the oilsands as well but lasted considerably longer than standard pipe. Standard pipe would wear out in less than 3 month's and hardfaced pipe would sometimes last over a year. The shop kept very busy making spare pipe to replace the worn out pipe.