The B&K 521-400HC is a high-performance black iron cap designed to securely seal the end of a piping system in industrial, commercial, and residential applications. Manufactured from durable malleable iron and finished with a black coating, this fitting is engineered for strength, reliability, and corrosion resistance in demanding environments.

With a 1/8-inch Female Iron Pipe (FIP) connection, this cap is ideal for terminating pipe runs that carry non-potable fluids such as lubricants, oils, greases, liquefied petroleum (LP) gases, natural gases (including nitrogen and oxygen), steam, and diesel. It is not intended for use in potable water systems.

The cap features precision threading that complies with ANSI/ASME B1.20.1 standards, ensuring a tight and leak-resistant seal. Rated for up to 500 PSI at 150°F, it is suitable for high-pressure systems and meets ASTM and ASME specifications. Its malleable iron construction allows for a secure fit due to the relative softness of the metal, which helps form a reliable seal.

Key Features

• Size: 1/8 inch inlet diameter
• Connection Type: Female Iron Pipe (FIP)
• Material: Malleable iron
• Finish: Black coating for corrosion resistance
• Threading: ANSI/ASME B1.20.1 compliant
• Pressure Ratings:
  • Working Pressure: 232 PSI
  • Maximum Pressure: 300 PSI
  • Rated up to 500 PSI at 150°F
• Temperature Range:
  • Minimum: -20°F
  • Working: 77°F
  • Maximum: 347°F
• Dimensions:
  • Length: 0.71 in
  • Height: 0.55 in
  • Width: 0.71 in
  • Weight: 0.030 lbs
• Class: 150-lb malleable fittings
• Warranty: 1-year limited warranty
• Brand: Southland
• Unit of Measure: Each

Applications

• Sealing the end of non-potable piping systems
• Transport of:
  • Lubricants
  • Oils
  • Grease
  • LP gases
  • Natural gases (e.g., nitrogen, oxygen)
  • Steam
  • Diesel
• Industrial and commercial fluid systems
• DIY plumbing and mechanical projects