Weld Neck Flange 20 Inch Class 150 Posted on February 12, 2017July 1, 2017 Weld Neck Flange 20 Inch Class 150 Weld Neck Flange Class 150 Size NPS : 20″ Size DN : 500 mm. Weight : 82 kg. StudBolt Size : 1 1/8″ UNC Or (M30) x 160 Long No. of Bolts : 20 EA. Holes Diamater : 31.75 mm. [wpfilebase tag=file id=2201 /] ansi b16 5 ansi flange dimensions ansi flanges asme b16 5 Class 150 flange dimensions raised face flange Weld Neck Flange Weld Neck Flange Class 150