20"×20" Square Ductile Iron Cover & Frame
Utility vault and valve box square access
20"×20" square ductile iron cover and frame for utility vaults, valve boxes, and square sanitary access. Cast to ASTM A536 Grade 65-45-12, D400 traffic-rated, with custom markings and locking options.
| Product Code | LZB-DI-S20-D400 |
|---|---|
| Clear Opening | 20"×20" (500×500 mm) |
| Overall Size | ~24"×24" OD frame (610×610 mm) |
| Cover Thickness | ~1.5" (38 mm) |
| Frame Height | ~4"–6" (100–150 mm) |
| Material | Ductile Iron QT500-7 |
| U.S. Material Equivalent | ASTM A536 Grade 65-45-12 |
| Load Rating | D400 / AASHTO H-20 |
| Assembly Weight | 130–175 lb (60–80 kg) assembly |
| Surface Finish | Black bituminous coating |
| Marking | Customizable — utility ID, project marking, city logo |
| Locking | Bolt-down optional; hinge or lift-off configuration available |
- · ASTM A536 Grade 65-45-12
- · AASHTO H-20 / D400
Sized to the common 20" square utility-vault opening used across U.S. municipal and utility specifications; project-specific drawing review available.
Why specify this
- ✓ Square access opening — easier alignment with valve and equipment chambers
- ✓ D400 traffic-rated for in-street and intersection use
- ✓ Configurable as hinged or lift-off cover
- ✓ Compatible with standard precast and cast-in-place vault openings
- ✓ Custom marking and slot patterns available
Square covers are the right call when the buried chamber is square — typical for valve vaults, equipment enclosures, and many telecom or electrical service boxes. A round cover over a square chamber wastes precast volume and leaves awkward concrete fillet work; matching the cover shape to the chamber shape keeps the install clean.
This 20”×20” set is sized for the common SoCal utility vault footprint and ships standard with a black bituminous coating. Lid markings (utility name, asset ID, project tag) and locking options (M-bolt, pentagon, or municipal-standard lock) are confirmed per RFQ.
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