Weld Fittings are used on permanent installations where process piping and equipment can be cleaned in place (CIP) and removal from the system is not required. Weld Fittings are offered in nominal tube sizes 1/2" through 12" in T304 and T316L materials. Uniform wall thickness for 1/2" through 3" sizes measure .065 (16 ga). In 4" size, wall thickness measures .083 (14 ga), 6" and 8" .109 (12 ga).VNE offers Polished ID and OD Fittings for immediate shipment. Other polished combinations may be ordered. Our Weld Fittings meet all 3A requirements.