Description
4″ x 24″ Bolted Watertight Manhole Frame and Cover
The 4″ x 24″ Bolted Watertight Manhole Frame and Cover is a gasketed cast iron access assembly engineered for underground structures where infiltration control, operational security, and environmental protection are critical design requirements. Combining a precision-machined frame, compression gasket system, and bolted cover configuration, this assembly provides a positive seal designed to minimize surface water intrusion while protecting critical utility infrastructure.
Manufactured from ASTM A48 Class 30 gray cast iron and suitable for H-20 highway loading conditions, this access casting is frequently specified for sanitary sewer networks, wastewater collection systems, lift stations, wet wells, flow monitoring structures, valve vaults, and utility chambers exposed to groundwater, stormwater runoff, or flood-prone conditions.
Unlike conventional loose-fit covers, the bolted watertight configuration utilizes mechanical fastening and gasket compression to create a more secure and reliable seal. This helps reduce inflow and infiltration (I&I), minimizes odor migration, and protects infrastructure assets from unauthorized entry and environmental contamination.
Product Features
- Bolted watertight cover assembly
- Neoprene gasket sealing system
- ASTM A48 Class 30 gray iron construction
- H-20 highway traffic loading
- 24″ access opening
- 4″ frame profile
- Compression-seal design
- Precision-machined seating surfaces
- Corrosion-resistant construction
- Positive mechanical fastening
- Available with custom utility markings
- Suitable for municipal and industrial installations
- Compatible with precast and cast-in-place structures
Ideal Applications
The 4″ x 24″ Bolted Watertight Frame and Cover is commonly specified for:
- Sanitary Sewer Manholes
- Wastewater Collection Systems
- Lift Stations
- Wet Wells
- Force Main Structures
- Valve Vaults
- Flow Meter Chambers
- Sewer Overflow Structures
- Pump Control Stations
- Utility Vaults
- Electrical Access Chambers
- Telecommunications Infrastructure
- Industrial Process Facilities
- Flood-Prone Utility Installations
These environments often require enhanced protection from groundwater infiltration, stormwater inflow, unauthorized access, and odor migration.
Technical Specifications
| Property | Specification |
|---|---|
| Product Type | Bolted Watertight Manhole Frame & Cover |
| Material | ASTM A48 Class 30 Gray Iron |
| Loading Classification | H-20 Highway Loading |
| Cover Diameter (C) | 24″ |
| Clear Opening (E) | 23.5″ |
| Frame Inside Diameter (F) | 25″ |
| Outside Frame Diameter (G) | 31.5″ |
| Frame Depth (D) | 4″ |
| Cover Thickness (H) | 1.5″ |
| Gasket Type | Neoprene Compression Gasket |
| Fastening System | Mechanical Bolt-Down |
| Cover Style | Solid Watertight Cover |
Dimensional Information
| Dimension | Description | Measurement |
|---|---|---|
| C | Cover Diameter | 24″ |
| D | Frame Depth | 4″ |
| E | Clear Opening | 23.5″ |
| F | Frame Inside Diameter | 25″ |
| G | Outside Frame Diameter | 31.5″ |
| H | Cover Thickness | 1.5″ |
The compact 4-inch frame profile allows installation where shallower casting depths are preferred while still providing sufficient bearing area and structural performance for traffic-rated applications.
Watertight Sealing Technology
One of the primary advantages of this assembly is its ability to provide a secure seal between the frame and cover.
Groundwater Infiltration Reduction
Municipal wastewater systems often experience significant treatment costs associated with unwanted groundwater entering collection systems. Gasketed castings help reduce infiltration by creating a controlled sealing surface between mating components.
Stormwater Exclusion
During heavy rainfall events, bolted watertight covers help prevent surface runoff from entering underground utility structures and overloading collection systems.
Odor Containment
The compression gasket assists in limiting odor migration from wastewater facilities, helping improve conditions in residential, commercial, and public spaces.
Environmental Protection
Watertight access systems help protect sensitive infrastructure from contaminants, debris, and environmental exposure.
Mechanical Bolt-Down Security
The bolted fastening system provides additional benefits beyond sealing performance.
Asset Protection
Mechanical fasteners help prevent unauthorized entry into underground utility structures.
Cover Stability
Bolted assemblies resist displacement caused by traffic vibration, hydraulic surcharging, flooding events, and accidental movement.
Public Safety
Secure fastening helps reduce the potential for cover movement in high-traffic environments.
Infrastructure Reliability
Critical utility assets remain protected during severe weather events and changing site conditions.
Material Performance Characteristics
| Property | Performance |
|---|---|
| Compressive Strength | Excellent |
| Structural Integrity | Excellent |
| Corrosion Resistance | High |
| Abrasion Resistance | High |
| Impact Resistance | High |
| Freeze-Thaw Durability | Excellent |
| Service Life | 30+ Years Typical |
Gray cast iron remains one of the most widely specified materials for municipal access castings because of its proven performance under traffic loading, environmental exposure, and long-term service conditions.
Available Utility Markings
Amercast can provide cast-in identification markings including:
- SANITARY SEWER
- SEWER
- STORM
- DRAIN
- WATER
- ELECTRIC
- TELECOMMUNICATIONS
- FIBER OPTIC
- GAS
- RECLAIMED WATER
- MUNICIPAL LOGOS
- CUSTOM LETTERING
Custom utility branding and agency-specific identification can be incorporated during manufacturing.
Custom Manufacturing Options
Amercast manufactures specialty castings for municipalities, utility authorities, engineers, and contractors throughout North America.
Available customization options include:
- Watertight Configurations
- Locking Assemblies
- Alternate Gasket Materials
- Custom Cover Markings
- Utility-Specific Castings
- Ductile Iron Alternatives
- Specialty Coatings
- Security Hardware
- Municipality Logos
- Project-Specific Designs
Our team routinely develops casting solutions tailored to utility standards, DOT requirements, and consulting engineer specifications.
Common Benefits of Gasketed Utility Access Systems
| Benefit | Advantage |
|---|---|
| Infiltration Control | Reduces groundwater entry |
| Odor Management | Limits odor migration |
| Flood Protection | Restricts stormwater intrusion |
| Security | Prevents unauthorized access |
| Asset Preservation | Protects underground equipment |
| Regulatory Compliance | Supports wastewater system performance |
Related Products
- Manhole Frames and Covers
- 6″ x 24″ Locking Watertight Manhole Frame and Cover
- 6″ x 24″ Heavy Duty Manhole Frame and Cover
- 3″ x 24″ Locking Watertight Septic Manhole Frame and Cover
- Adjustable Manhole Risers
- Manhole Risers and Extension Rings
- Catch Basin Grates
- Municipal Castings
Industry Resource
For additional guidance regarding collection system performance, infiltration reduction, and wastewater infrastructure best practices:
Water Environment Federation (WEF)
WEF provides technical resources, engineering guidance, and operational best practices for water and wastewater professionals throughout North America.
Why Choose Amercast?
Amercast manufactures cast iron access solutions for municipalities, utility authorities, consulting engineers, contractors, and infrastructure owners nationwide. Our gasketed and bolted access systems are engineered to provide dependable sealing performance, secure operation, and long-term durability in demanding field environments.
Whether your project requires a standard watertight casting, custom utility identification, specialized fastening systems, or specification-driven municipal products, Amercast can deliver a solution tailored to your project requirements.
Request a Quote
Need pricing, submittal drawings, CAD details, gasket specifications, utility markings, or project-specific engineering assistance?
Contact Amercast today to request a quote for the 4″ x 24″ Bolted Watertight Manhole Frame and Cover. Our team can assist with wastewater facilities, utility infrastructure, transportation projects, industrial applications, and municipal construction projects throughout North America.
