The Smith-Blair 411 steel fabricated coupling is a bolted sleeve type coupling designed for joining plain end pipe of the same diameters. This versatile coupling eliminates the need for welding or special pipe fittings, providing a reliable straight connection. The coupling allows for limited expansion and contraction while dampening vibration to reduce pipe fatigue. With good deflection capabilities, it allows change in piping direction without the need of elbows or bends. The 411 coupling is available in a wide variety of pipe O.D. sizes and sleeve lengths and can be custom made to fit odd O.D.s or other unusual applications. Steel sizes are built to specific O.D. and Ductile Iron sizes are built with range to accommodate the variances in Ductile Iron pipe O.D.s.

The 411 coupling is constructed with high-quality materials engineered for durability and performance. The sleeve is manufactured from ASTM A53, ASTM A512 or Carbon Steel having minimum yield of 30,000 PSI. Followers are made from Ductile Iron ASTM A536, Steel AISI C 1020, or A715 Grade 80 HSLA Steel, designed for a high strength-to-weight ratio with follower thickness determined by coupling size. Bolts and nuts are high strength, low alloy steel with heavy semi-finished hexagon nuts, with optional stainless steel and carbon steel ASTM A307 electro-galvanized with di-chromate seal. The gasket is Nitrile (Buna N) NSF 61 compounded to produce superior storage and performance characteristics while resisting water, acids, alkalies, most (aliphatic) hydrocarbon fluids, and other chemicals. The coupling features a Flexi-Coat Fusion Bonded Epoxy Finish and operates within a temperature range of -20°F to 180°F.

The 411 coupling provides a working pressure up to 150 PSI and is suitable for all types of pipe applications. HDPE applications require the use of stiffeners. The coupling meets applicable AWWA C219 Standards and is easy to install with no special pipe end preparation required. Available sizes range from ½ inch through 54 inches, with larger sizes available upon request. Most sizes will accommodate anchor studs to restrain the joints, and the coupling is provided with or without pipe stops to accommodate customer needs. It is important to note that this product does not restrain pipe movement, and proper anchoring is required to prevent pipe pullout.