ASTM A105 Flanges

ASTM A105 flanges are forged carbon steel flanges for ambient- and higher-temperature service in pressure systems. These flanges may be manufactured in accordance with a variety of standard specifications covering ASME B16.5, ASME B16.47, ASME B16.48, ASME B16.36, MSS SP 44, API 605, and API 6A, etc. Flanges made to ASTM A105 material are limited a maximum weight of 4540 kg.

Supply & Stock

ASTM A105 flanges available in stock.

Shijiazhuang Metalsin stocks and supplies a large volume of forged flanges in ASTM A105 material:

• ASME B16.5, sizes: 1/2″ ~ 24″, Class 150 through Class 2500, FF/RF/ RTJ.
• ASME B16.47, sizes: 26″ ~ 60″, Class 75 through Class 900, FF/RF/RTJ.
• API 6A Type 6B and Type 6BX, 2000 ~ 20000 psi, RTJ.
• Tailor-made flanges up to 72″ with thickness up to 300 mm.
• Flange types: W/N, S/O, BL, Threaded, SW, Lap Joint, LWN, Plate, Line Blank.

Manufacture & Heat Treatment

ASTM A105 flanges shall be manufactured as one piece by a hot-forging process. This hot-forging process, either die forging or open-die forging, is a compressive hot-working operation. The metal flows in the designed direction during plastic deformation to form a disc-like product that is near to the finished flange. The forging process also consolidates the material to produce an essentially wrought steel structure. The product is subsequently machined to the exact shape and size of finished flange.

The forging process of ASTM A105 welding neck flanges.

The forged carbon steel conforming to ASTM A105 is a Group 1.1 material according to ASME B16.5. Generally, heat treatment for A105 flanges in Class 150 and Class 300 is not necessarily required. For flanges above Class 300 or otherwise specified by end user, heat treatment, such as annealing, normalizing, or normalizing and tempering, or quenching and tempering, may be performed. The normalizing heat treatment is most frequently applied in which case the material will be marked as “ASTM A105N”.

Chemical Composition Requirements

Mechanical Properties

Pressure-Temperature Ratings

Pressure-temperature ratings indicate maximum allowable working gage pressures at certain temperatures. It is an important design criterion in piping industry. The pressure and temperature are expressed in bar units and degrees Celsius, or psi units and degrees Fahrenheit respectively. The pressure-temperature ratings of ASTM A105 flanges made in accordance with ASME B16.5 and ASME B16.47 are listed in Table 1-1, Table 1-2, Table 2-1, and Table 2-2.

Pressure-temperature ratings for ASTM A105 flanges in bar units and degree Celsius are listed in Table 1-1 and Table 1-2; Pressure-temperature ratings for ASTM A105 flanges in psi units and degrees Fahrenheit are listed in Table 2-1 and Table 2-2. The tabulated values of Class 75 through Class 900 are applicable to A105 flanges manufactured in accordance with ASME B16.47. The tabulated values of Class 150 through Class 2500 are applicable to A105 flanges manufactured in accordance with ASME B16.5. Although permissible, ASTM A105 flanges are not recommended for prolonged use above 425°C [800°F], since carbide phase of steel may be converted to graphite in this situation.

Applicability in ASME Codes

The ASTM A105 is designated with the UNS number of K03504. The welding P-number and Group-number are 1 and 2 respectively. Its ASTM or ASME equivalent is ASTM A181 Class 70. The ASTM A105 flanges may be applied to services of ASME Boiler and Pressure Vessel Codes, ASME B31.1 and ASME B31.3. The maximum allowable stresses, basic allowable stresses, and allowable stresses of ASTM A105 are specified in the Codes mentioned formerly.