Mechanical Joint Pipe
The AMERICAN mechanical joint, furnished in pipe sizes 4” to 12” and in fitting sizes 4” to 48”, is a flexible stuffing box type connection used primarily in underground service.
The AMERICAN mechanical joint was developed by the American Cast Iron Pipe Company and first marketed in 1929. Since that time, millions of feet of AMERICAN pipe equipped with this joint have been installed to give dependable service across the nation and in many foreign countries. The joint is designed with a stuffing box into which a rubber gasket is compressed by a ductile iron gland drawn up with low-alloy steel bolts. It affords liberal deflection before joint compression and allows expansion and contraction of the line without leakage. It is rated for a water working pressure of up to 350 psi.
Originally designed to meet the rigid requirements of the gas industry for a pressure-tight joint, the AMERICAN mechanical joint was instrumental in starting a nationwide trend toward rubber-packed joints for water service as well as gas service. Its design was widely accepted and it soon became the standard joint of the iron pipe industry.
The popularity of the AMERICAN mechanical joint among utility officials, contractors and engineers steadily increased until the majority of cast iron piping furnished for gas, water, sewage and other services was equipped with this joint. However, push-on joint pipes, which are less labor intensive and compatible with push-on or mechanical joint fittings, currently make up the vast majority of ductile iron pipelines being installed for underground service. Mechanical joint pipe is now used to a much lesser extent.
The AMERICAN mechanical joint meets the requirements of ANSI/AWWA C110/A21.10 and ANSI/AWWA C111/A21.11.
AMERICAN ductile iron mechanical joint pipe is centrifugally cast in nominal 20’ laying lengths under rigid production and quality control procedures in accordance with ANSI/AWWA Standards. AMERICAN mechanical joint ductile iron pipe is produced in 4”-12” sizes and in special thickness class 53 only.
The AMERICAN mechanical joint provides easy installation under the most adverse conditions. Plain rubber gaskets of SBR are normally used for water and domestic sewage service. Fabric tipped plain rubber gaskets are available, as well as other special gaskets such as oil-resistant rubber. Plain rubber gaskets or tipped gaskets are used for air or liquid temperatures up to 120°F. For applications involving temperatures in excess of 120°F, or for other special service applications, and for installations in contaminated soils where permeation through gaskets might be a concern, consult AMERICAN for recommendations. See Table No. 2-6.
Standard joint accessories furnished with mechanical joint pipe and fittings include ductile iron glands, low-alloy steel tee head bolts with hex nuts and plain rubber gaskets.