I know how to pipe weld anywhere from * inch pipe to 12 inch pipe. Ive welded mig for two years and I can weld up hill over head flatI know how to pipe weld anywhere from 2 inch pipe to 12 inch pipe. Ive welded mig for two years and I can weld up hill over head flatI know how to pipe weld anywhere from 2 inch pipe to 12 inch pipe. Ive welded mig for two years and I can weld up hill over head flat