The Lap joint stub end is the fittings that are used in place of welded flanges when the support of rotating back up flanges is required. Lap Joints also named stub Ends and vanstone flared laps, it is used in place of welded flanges where rotating back up flanges are desired. Minimum lap thickness shall not be less than nominal wall thickness. Contact faces of stub ends shall have a concentric serration or spiral according to the purchaser's requirements. These lengths and radius apply for schedule 40s or thinner stainless steel pipes. Radius of fillet B is only effective to MSS SP-43 lap joint stub ends. Lap Joints are consisted of three series. Nominal Pipe Size Outside Diameter at Bevel Length Radius of Fillet Diameter of Lap A B NPS D L R G 1/