Smith-Blair Style 471 PipeLock Restraint Coupling - Ductile, 3-48 in

The Smith-Blair Style 471 Pipe-Lock is a fabricated steel restraint coupling that joins and restrains plain-end ductile iron pipe to plain-end ductile iron pipe, with no other method of restraint required. The restraint is built into each follower gland: a Cam-Lock gland with multiple single-tooth wedges grips the pipe, and an MJ gasket seals each end.

It also serves to replace split or excessively damaged pipe. Sleeve length — 7, 10 or 16 in, depending on size — is chosen in Option 2.

Application: joining and restraining plain-end ductile iron pipe, 3 to 48 in.

Key Features

• Working pressure up to 350 PSI on ductile iron through 16 in
• Joins and restrains in one unit, with no other method of restraint required
• Restraint integral to the follower gland, with multiple single-tooth wedges
• Up to 5° deflection per gland at 4 to 12 in
• Certified to NSF/ANSI 61 and NSF/ANSI 372

Up to 350 PSI. The rating is set by pipe size and material; where the 471 joins pipes with different ratings, the lower-rated pipe sets the working pressure.

UL Listed installations: 350 PSI at 14-16 in, 250 PSI at 18 and 24 in, 200 PSI at 20 in (Cam-Lock TI-057).

Sleeve thickness by size is shown in Option 2. Materials subject to change by the manufacturer.

Plain-end ductile iron pipe at the ductile iron ODs listed, 3 to 48 in. Smith-Blair also rates the 471 for plain-end carbon steel pipe at IPS ODs in 3 to 12 in.

Choose the size in the first option; the part number shows in the last option.

Make any deflection after the joint is assembled and before the gland bolts are tightened.

• Inspect the shipment for transit damage and confirm the correct product before installing.
• Set the pipe gap at 1/2 to 3/4 in for a 7 in sleeve and 1/2 to 1-1/4 in for a 10 in sleeve.
• Assemble each end as a Cam-Lock mechanical joint: clean and lubricate the pipe end and gasket per AWWA C111, gasket taper toward the plain end, gland lip against the gasket; then tighten the gland bolts evenly (bottom, top, sides, then the rest) to the torque in the instructions.
• Use the black wedges on ductile iron pipe, never red PVC wedges. The Cam-Lock is not for use on plain-end fittings.
• Set the wedges: hand-tighten the torque-off nuts until every wedge touches the pipe, then turn each nut 1/2 turn in an alternating pattern until all twist off, never more than 1/2 turn on one nut at a time. Do not remove the retaining washer under the torque-off nut.

From Smith-Blair Installation Instructions TI-055 (Rev 4/16/24), in the Data Sheet tab, and Cam-Lock Installation Instructions TI-057.