Code of Federal Regulations Title 46. Shipping § 46.56.25–10 Flange facings

(a) Flange facings shall be in accordance with the applicable standards listed in table 56.60–1(b) and MSS SP–6 (incorporated by reference;  see 46 CFR 56.01–2).

(b) When bolting class 150 standard steel flanges to flat face cast iron flanges, the steel flange must be furnished with a flat face, and bolting must be in accordance with § 56.25–20 of this part. Class 300 raised face steel flanges may be bolted to class 250 raised face cast iron flanges with bolting in accordance with § 56.25–20(b) of this part.