ASTM A193 B7M Alloy Steel Full Threaded Stud Bolt with A194 2HM Heavy Hex Nuts NACE MR0175

Our ASTM A193 Grade B7M full threaded stud bolts are supplied as matched bolting assemblies with ASTM A194 Grade 2HM heavy hex nuts, fully compliant with NACE MR0175 / ISO 15156 for sour service in oil, gas and petrochemical piping systems. Both bolt and nut are hardness controlled and marked for full traceability.

• Hardness controlled for sour service: B7M studs are supplied at 235 HB max (HRC 22 max) and 2HM nuts at 95 HRB max, reducing susceptibility to sulfide stress cracking in wet H2S environments.
• Matched mechanical performance: 2HM nuts are proof load tested to match B7M stud tensile requirements, avoiding thread stripping in high pressure flange joints.
• Dimensional compliance: Threads to ASME B1.1 Class 2A (stud) and 2B (nut), dimensions to ASME B18.31.2 and ASME B18.2.2.

• Raw material verified by desktop direct-reading spectrometer
• 100% (every-piece) hardness testing on finished B7M studs and 2HM nuts
• Tensile and proof load testing per ASTM A193 / A194
• Magnetic particle inspection and Go / No-Go thread gauging
• Salt spray testing for coated variants

Wellhead and christmas tree assemblies, sour gas gathering lines, refinery and petrochemical flange joints, high pressure valve and heat exchanger bolting, transmission pipelines and compressor stations.

Studs and nuts packed as matched sets in cartons, on plywood pallets or in plywood cases with anti-moisture lining. Neutral or customer-branded labels available. 100 tons monthly capacity, 8-20 days lead time depending on size and quantity.

Send us your flange size, pressure class and quantity — we will quote a matched B7M / 2HM bolting set within one working day.