Ductile Iron Manhole Covers & Frames
ASTM A536 / AASHTO H-20 traffic-rated castings
Round and square covers and frames in ASTM A536 ductile iron — traffic-rated, anti-settlement, and precast-compatible.
- Standard sizes
- 12" to 40" clear opening
- Load range
- A15 / B125 to E600 · H-15 / H-20 / HS-20
Why this product family
- ✓ ASTM A536 Grade 65-45-12 ductile iron — superior strength and ductility over gray iron
- ✓ AASHTO H-20 / HS-20 traffic rated for highways, expressways, and freight routes
- ✓ Anti-settlement wide rim distributes load to prevent road surface settling
- ✓ Precast-compatible tolerances drop into standard U.S. concrete manhole cones
- ✓ Custom marking — SEWER / STORM / city name / utility logo / project ID
- ✓ Bolt-down and elastic locking options for high-traffic and watertight applications
Ductile iron is the U.S. workhorse for sanitary sewer, storm drainage, and utility access covers carrying vehicular loads. Our castings meet the ASTM A536 65-45-12 grade referenced by most U.S. utility specifications, with frame and cover sets engineered to fit standard precast concrete cones without field rework.
For SoCal projects we routinely match SPPWC 630-5 (24” sewer), SPPWC 633-5 (36” sewer), and SPPWC 311-4 (catch basin) configurations, and can supply AASHTO M306 proof-load documentation on request.
3 configurations
24" Round Ductile Iron Manhole Cover & Frame
AASHTO H-20 traffic rated, anti-settlement design
20"×20" Square Ductile Iron Cover & Frame
Utility vault and valve box square access
28"×32" Square Frame, Round Opening — Ductile Iron
Precast-friendly square frame with round access lid
Don't see your exact size or marking?
Custom dimensions, lid markings, frame details, and OEM/private label are standard for our integrated factory. Send your drawing or SPPWC plan number.
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