Smith-Blair · Restraint Coupling
Style 473 Pipe-Lock Restraint Coupling
Fabricated Steel, PVC x Ductile Iron or Steel
235 PSI Max Working Pressure
-20°F to +180°F Temperature
SBR MJ Gasket
Epoxy-Coated Steel Sleeve
Ductile Iron Cam-Lock Glands
Low-Alloy Steel Studs
NSF/ANSI 61 and 372
Restrained Joint, 5° Max Deflection
3.50-38.30 in Pipe OD
29-989 lb Weight
Description
The Smith-Blair Style 473 Pipe-Lock is a fabricated steel transition restraint coupling that joins and restrains plain-end PVC pipe to plain-end ductile iron pipe, or PVC to plain-end steel. It comes as a complete unit, with the restraint built into each follower gland: a Cam-Lock PVC restraint on the PVC end, a Cam-Lock ductile iron restraint on the iron end, and an MJ gasket sealing each side.
Multi-Seal builds at 4 to 12 in (catalog suffix -243 and -343) take both IPS and ductile iron OD PVC on the PVC end. Sleeve length — 7, 10 or 16 in, depending on size — is chosen in Option 2.
Application: transitioning and restraining plain-end PVC to plain-end ductile iron or steel pipe, 3 to 36 in.
Key Features
- Rated at the lower of the two pipes, up to 235 PSI on the PVC end
- Comes as a complete unit — sleeve, PVC and ductile iron restraint glands, gaskets and studs
- Restraint integral to each follower gland, with multiple single-tooth wedges
- Multi-Seal gasket builds take IPS or ductile iron OD PVC at 4 to 12 in
- Certified to NSF/ANSI 61 and NSF/ANSI 372
What Ships and What It Needs to Run
Included: the complete unit — epoxy-coated steel sleeve, a Cam-Lock PVC restraint gland and a Cam-Lock ductile iron restraint gland, MJ gaskets (Multi-Seal on -243/-343 builds; Smith-Blair MJ gaskets at 30 and 36 in), and studs, nuts and washers.
Genuine Smith-Blair equipment, factory-new in original packaging — sold and supported by Watermain Supply, an independent industrial supplier.
12-Month Smith-Blair Warranty
Smith-Blair warrants its products to be free of defects in materials and workmanship for one year from the date of shipment by Smith-Blair. Dated proof of purchase, such as a bill of sale, is required to establish eligibility. Smith-Blair will repair or, at its option, replace a defective product; the product is returned to the factory or warehouse Smith-Blair designates.
Working Pressure
Up to 235 PSI. The 473 is rated at the lower of the two pipes it joins, which is normally the PVC: the PVC end takes the pressure rating of the PVC pipe, set by its standard and DR.
| PVC pipe |
Working pressure |
| AWWA C900 DR14, DI OD |
235 PSI |
| AWWA C900 DR18, DI OD |
235 PSI |
| AWWA C900 DR25, DI OD |
165 PSI |
| AWWA C905 DR18, DI OD |
235 PSI |
| AWWA C905 DR25, DI OD |
165 PSI |
| ASTM D2241 SDR17, IPS OD |
235 PSI |
| ASTM D2241 SDR21, IPS OD |
200 PSI |
| ASTM D2241 SDR26, IPS OD |
160 PSI |
Rating of the PVC end; the joint takes the lower of the two pipes. The ductile iron end is rated 350 PSI through 16 in and 250 PSI above; a steel end 250 PSI at 3-12 in. Any PVC class: 150 PSI at 30 in, 125 PSI at 36 in. DR14 and SDR17 are shown at the 235 PSI ceiling of the Cam-Lock 120 PVC restraint spec.
Materials Specifications
| Sleeve |
Fabricated carbon steel, ASTM A283 Gr C or carbon steel with 30,000 PSI minimum yield (ASTM A513 or A53 on 3-4 in per the 477 sleeve spec) |
| Sleeve finish |
Flexi-Coat fusion-bonded epoxy |
| Restraint glands |
Cam-Lock 120 (PVC end) and Cam-Lock 111 (ductile iron or steel end), ductile iron 65-45-12, ASTM A536 |
| Wedges |
Single-tooth ductile iron: red, heat treated to RC 45, on the PVC end; black, heat treated for ductile iron pipe, on the iron end |
| Breakaway nuts |
Carbon steel or cast iron |
| Actuating bolts |
Ductile iron 60-40-18, ASTM A536 |
| Gland finish |
Flexi-Coat fusion-bonded epoxy per AWWA C213; wedges and actuating bolts E-coated epoxy |
| Gasket |
SBR mechanical joint gasket per ANSI/AWWA C111/A21.11 or Multi-Seal gasket; Smith-Blair MJ gasket at 30 and 36 in |
| Studs and nuts |
High-strength low-alloy steel per AWWA C111/A21.11 and/or ASTM A193 Gr B7, rolled threads |
| Washers |
Carbon steel per ASTM A108, electro-galvanized with dichromate seal per ASTM B633 |
Materials subject to change by the manufacturer.
Pipe Applications
Plain-end PVC (AWWA C900/C905 at ductile iron ODs, or ASTM D2241 at IPS ODs) to plain-end ductile iron, 3 to 36 in, or to plain-end steel at 3 to 12 in. Smith-Blair limits PVC applications to SDR 26 or heavier wall.
Sizes
23 sizes from 3.50 to 38.30 in OD — open for the full list
| Pipe size and OD |
Sleeve thk x length |
| 3 in - PVC 3.50 x DI 3.96 in OD |
0.250 x 7 in |
| 4 in - PVC 4.50 x DI 4.80 in OD |
0.250 x 7 in |
| 4 in - PVC 4.50-4.80 x DI 4.80 in OD |
0.250 x 7 in |
| 4 in - PVC 4.80 x DI 4.80 in OD |
0.250 x 7 in |
| 6 in - PVC 6.63 x DI 6.90 in OD |
0.250 x 7 in |
| 6 in - PVC 6.63-6.90 x DI 6.90 in OD |
0.250 x 7, 0.250 x 10 in |
| 6 in - PVC 6.90 x DI 6.90 in OD |
0.250 x 10 in |
| 8 in - PVC 8.63 x DI 9.05 in OD |
0.250 x 7 in |
| 8 in - PVC 8.63-9.05 x DI 9.05 in OD |
0.250 x 7, 0.250 x 10 in |
| 8 in - PVC 9.05 x DI 9.05 in OD |
0.250 x 10 in |
| 10 in - PVC 10.75 x DI 11.10 in OD |
0.250 x 7, 0.250 x 10 in |
| 10 in - PVC 10.75-11.10 x DI 11.10 in OD |
0.250 x 7, 0.250 x 10 in |
| 10 in - PVC 11.10 x DI 11.10 in OD |
0.250 x 7, 0.250 x 10 in |
| 12 in - PVC 12.75 x DI 13.20 in OD |
0.250 x 7, 0.250 x 10 in |
| 12 in - PVC 12.75-13.20 x DI 13.20 in OD |
0.250 x 7, 0.250 x 10 in |
| 12 in - PVC 13.20 x DI 13.20 in OD |
0.250 x 7, 0.250 x 10 in |
| 14 in - PVC 15.30 x DI 15.30 in OD |
0.250 x 7, 0.250 x 10 in |
| 16 in - PVC 17.40 x DI 17.40 in OD |
0.250 x 7, 0.250 x 10 in |
| 18 in - PVC 19.50 x DI 19.50 in OD |
0.250 x 7, 0.250 x 10 in |
| 20 in - PVC 21.60 x DI 21.60 in OD |
0.250 x 7, 0.250 x 10 in |
| 24 in - PVC 25.80 x DI 25.80 in OD |
0.250 x 7, 0.250 x 10 in |
| 30 in - PVC 32.00 x DI 32.00 in OD |
0.250 x 10, 0.250 x 16 in |
| 36 in - PVC 38.30 x DI 38.30 in OD |
0.250 x 10, 0.250 x 16 in |
Choose the size in the first option; the part number shows in the last option.
Max Joint Deflection
| Nominal size |
Per gland |
| 3 in |
3° |
| 4 to 12 in |
5° |
| 14 and 16 in |
2° |
| 18 to 24 in |
1.5° |
| 30 in and up |
1° |
Make any deflection after the joint is assembled and before the gland bolts are tightened.
Installation Notes
- 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.
- Red wedges go on the PVC end and black wedges on the ductile iron or steel end — never swap them. The Cam-Lock 120 is limited to SDR 26 or heavier PVC and 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.
Before You OrderAll Smith-Blair products are Made to Order and Non-Returnable.
Items typically shipped in 5 - 10 business days.
PVC-to-steel builds, 304 or 316 stainless hardware, other gasket materials and longer sleeves are built to order — email sales@watermainsupply.com with both pipe ODs and the PVC class.
