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Mechanical Coupling-to-Flange Transition — Steel & Cast Iron Pipe, 3 in through 24 in
Overview
The Dresser Style 128 Flange Adapter is a fabricated steel fitting that converts a plain-end pipe into a flanged connection without welding, threading, or costly pipe modification. One end uses the proven Dresser coupling design — a wedge-section rubber gasket compressed by a follower ring and AWWA bolts — to seal against the pipe OD. The opposite end is a full-face steel flange that bolts directly to any mating AWWA C-207 Class D flanged fitting, valve, pump, or appurtenance.
The Style 128 is available for both steel pipe and cast/ductile iron pipe across a full range of nominal sizes from 3 in through 24 in. Where standard flanges are not adequate, Dresser can fabricate to ANSI 150, ANSI 300, or other U.S. and international flange standards. An insulating design is available for applications requiring cathodic isolation, and a lock-pin variant can be supplied to anchor the coupling against pipe pullout under pressure thrust.
Key Features
Materials of Construction
| Component | Material | Notes |
|---|---|---|
| Followers | AISI C1012 or ASME SA36 Steel | Single piece through 12 in |
| Body Ring (Middle Ring) | ASTM A513 / ASTM A635 / ASME SA675 Gr.60 | High-strength steel construction |
| Flange | AWWA C-207 Class D | Standard; ANSI 150 & 300 available |
| Bolts | AWWA C111 / ANSI A21.11 | E-coated steel standard |
| Gaskets | Grade 27 BUNA-S (SBR) | Potable water safe; other compounds available |
| Coating | Fusion-Bonded Epoxy | Interior & exterior; RED-D shopcoat optional |
Specifications — 150 MAOP All Sizes (3 in – 24 in)
Dimensions: Body ring thickness x length (in). Overall dimensions: coupling diameter x length. Flange OD per AWWA C-207 Class D.
| Nom. Size (in) | Pipe OD (in) | Body Ring Thick x Len | Bolts No./Diam x Len | Overall Diam x Len | Flange OD (in) | Ship Wt (lbs) |
|---|---|---|---|---|---|---|
| 3 | 3.500 | .156 x 7 | 4 – 5/8 x 4 | 7-3/8 x 8-5/8 | 7.50 | 20 |
| 3 CIP | 3.74 – 4.02 | .188 x 7 | 4 – 5/8 x 4 | 7-3/4 x 8-11/16 | 9.00 | 25 |
| 4 | 4.500 | .188 x 7 | 4 – 5/8 x 4 | 8-3/4 x 8-13/16 | 9.00 | 25 |
| 4 CIP | 4.74 – 5.06 | .229 x 7 | 4 – 5/8 x 4 | 9 x 9-1/16 | 9.00 | 167 |
| 6 | 6.625 | 1/4 x 7 | 6 – 5/8 x 4 | 10-1/2 x 9-1/16 | 11.00 | 38 |
| 6 CIP | 6.84 – 7.16 | 1/4 x 7 | 6 – 5/8 x 4 | 11-13/16 x 9-1/16 | 11.00 | 36 |
| 8 | 8.625 | 1/4 x 7 | 6 – 5/8 x 4 | 12-7/16 x 9-1/16 | 13.50 | 52 |
| 8 CIP | 8.99 – 9.36 | 1/4 x 7 | 6 – 5/8 x 4 | 13-1/2 x 9-1/16 | 13.50 | 48 |
| 10 | 10.750 | 1/4 x 7 | 8 – 5/8 x 4 | 14-5/8 x 9-3/16 | 16.00 | 58 |
| 10 CIP | 11.04 – 11.46 | 3/8 x 7 | 8 – 5/8 x 4 | 15-9/16 x 9-3/16 | 16.00 | 69 |
| 12 | 12.750 | 1/4 x 7 | 8 – 5/8 x 4 | 16-3/4 x 9-11/16 | 19.00 | 79 |
| 12 CIP | 13.14 – 13.56 | 3/8 x 7 | 8 – 5/8 x 4-1/2 | 17-3/16 x 9-11/16 | 19.00 | 95 |
| 14 | 14.000 | 3/8 x 7 | 10 – 5/8 x 18 | 18 x 9-3/4 | 21.00 | 89 |
| 14 CIP | 15.30 | 3/8 x 7 | 10 – 5/8 x 4-1/2 | 19-3/8 x 9-3/4 | 21.00 | 112 |
| 16 | 16.000 | 3/8 x 7 | 10 – 5/8 x 4 | 21-7/16 x 9-3/4 | 23.50 | 103 |
| 16 CIP | 17.40 | 3/8 x 7 | 10 – 5/8 x 4-1/2 | 19-3/8 x 9-3/4 | 23.50 | 132 |
| 18 | 18.000 | 3/8 x 7 | 10 – 5/8 x 4-1/2 | 22 x 9-3/4 | 25.00 | 112 |
| 18 CIP | 19.50 | 3/8 x 7 | 10 – 5/8 x 4-1/2 | 23-1/2 x 9-3/4 | 25.00 | 151 |
| 24 | 24.000 | 3/8 x 7 | 14 – 5/8 x 4-1/2 | 18 x 10 | 32.00 | 184 |
| 24 CIP | 25.80 | 3/8 x 7 | 10 – 5/8 x 4-1/2 | 29-13/16 x 10 | 32.00 | 230 |
150 PSI MAOP all sizes. Higher-pressure flanges to ANSI 150# and 300# available on request. Consult factory for insulating and lock-pin designs.
Installation Instructions
? ANCHORAGE REQUIRED: The Style 128 provides a pressure seal only at the coupling end. Where pipe pullout could occur under pressure thrust, the assembly MUST be anchored or the lock-pin option specified. Failure to anchor where required can result in pipe separation, property damage, injury, or death.
Questions? Contact us at sales@watermainsupply.com or call 281.664.8000.
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