... ; 2)sour service models to NACE MR-01-75 The API oil hammer union can be used for cementing ... , Seal Ring; Sour Service Models to NACE MR-01-75. Recommended service General-service manifolds and lines. Features ... Sub, Seal Ring; Sour Service Models to NACE MR-01-75. Recommended service Cementing, fracturing, acidizing, testing, and ... Retainer Ring; Sour Service Models to NACE MR-01-75. API Hummer Union