weld neck flange 4 Inch Class 900 Posted on February 11, 2017July 1, 2017 weld neck flange 4 Inch Class 900 Weld Neck Flange Class 900 Size NPS : 4″ Size DN : 100 mm. Weight : 23 kg. StudBolt Size : 1 1/8″ UNC Or (M30) x 170 Long No. of Bolts : 8 EA. Holes Diamater : 31.75 mm. [wpfilebase tag=file id=2114 /] ansi b16 5 ansi flange dimensions ansi flanges asme b16 5 Class 900 flange dimensions raised face flange Weld Neck Flange weld neck flange Class 900