Restraint for standardized mechanical joints shall be incorporated in the design of the follower gland and shall impart multiple points of wedge action against the pipe, increasing its resistance as the pressure increases. The assembled joint shall maintain its flexibility after burial and shall maintain its integrity by a controlled and limited expansion of each joint during the wedging action. Restraining glands shall be manufactured of high strength ductile iron, conforming to the requirements of ASTM A536. Wedges shall be contoured to properly fit on the pipe and shall be manufactured of ductile iron, heat-treated to a minimum hardness of 370 BHN. Dimensions of the glands shall be such that they can be used with the standardized mechanical joint bell and tee head bolts conforming to the requirements of ANSI/AWWA C111/A21.11 and ANSI/AWWA C153/A21.53 of latest revision. Twist-off heads shall be incorporated in the design of the wedge actuating screws to ensure proper torque. All ductile iron components shall be phosphate washed and coated with an electrostatically applied, heat cured epoxy coating. The restraining device shall have a water working pressure rating of 350 PSI in sizes 3" through 16" and 250 PSI in sizes 18" and larger with a safety factor of at least 2:1 against separation when tested in a dead-end situation. Restraint device shall be Uni-Flange Series 1400 or approved equal.
FORD Uni-Flange® Retainer Gland, Wedge Action, Series: 1400-DA, 4 in Pipe, 4.8 in OD, 350 psi, 2 Wedges, Mechanical Joint, Ductile Iron, Black Armorguard E-Coated, For Use With: Ductile Iron Pipe