
24" T-Handle Flush Manhole with Deck Ring (Model #TH430-24A) - Painted Steel
Strongback style flush manholes provide easy, reliable access to tanks and compartments with a single T-handle operation. This 24" manhole is constructed of painted steel for durable service in demanding commercial marine environments while maintaining a low-profile, flush installation.
Design & Function
The Model TH430-24A is engineered specifically to provide rapid, tool-free access while maintaining robust boundaries between deck levels and internal tanks. The recessed T-handle drops into a flush well when not in use, keeping the deck unobstructed and completely safe for high-traffic operations, moving machinery, and cargo positioning.
Intended Use Cases:
- Tank Isolation & Access: Reliable watertight sealing for secure access to fuel oil storage, water ballast tanks, and specialized marine service tanks.
- Below-Deck Inspections: Streamlined entry for rapid safety checks, structural monitoring, and preventative maintenance of dry voids, cofferdams, and under-deck compartments.
- Containment Space Clean-Out: Ideal for storage holds and service lockers requiring frequent opening for washdowns or clean-outs.
- Fleet Maintenance & Retrofits: Sized to match standard industry deck footprints, making it the preferred drop-in replacement or retrofit manhole for existing hull repairs.
Primary Industries & Vessel Types:
- Workboats & Fleet Transport: Heavily utilized on commercial workboats, harbor tugs, push boats, and high-speed crew transport vessels.
- Inland & Coastal Barges: Sized perfectly for deck flats on liquid cargo barges, deck barges, and fleeting operations.
- Commercial Fishing & Processing: Built to withstand the continuous washdowns and organic tracking found on commercial fishing trawlers and processing ships.
- Offshore Energy & Utilities: Robust enough for the extreme sea states encountered by offshore supply vessels (OSVs) and utility workboats.
- Marine Infrastructure: Suitable for non-vessel installations including floating docks, transfer terminals, and municipal marine facilities.
Key Features
- Flush Deck Profile: Designed for a 0" profile height, providing a flat, completely flush deck installation that eliminates tripping hazards and allows unobstructed cargo handling or vehicle traffic.
- Heavy-Duty Structural Construction: Manufactured with a robust structural steel cover plate and matching deck ring for maximum strength, durability, and impact resistance on commercial work decks.
- Single T-Handle Operation: Engineered with an integrated single T-handle mechanism for quick, effortless, and tool-free access to tanks and dry compartments.
- Secure Strongback Closure: Utilizes a high-strength galvanized steel strongback design to distribute compression forces evenly across the perimeter frame, ensuring a secure, dependable watertight enclosure.
- Corrosion-Resistant Hardware: Outfitted with a premium stainless steel T-bolt assembly to ensure smooth mechanical articulation, superior corrosion resistance in saltwater spray, and consistent sealing force.
- Buna-N Oil-Resistant Gasket: Equipped with a standard premium Buna-N (Nitrile) rubber gasket, offering excellent resistance to fuel, oil, and chemical degradation for zero-leak containment.
- Universal Shipyard Finish: Delivered shot-blasted and coated with a universal shipyard primer (painted), making the assembly ready for immediate welding and final topcoat application at the shipyard.
Installation
- Qualified Personnel Requirement: Installation of the 24” T-handle strong-back flush manhole must be performed by qualified marine welders or fitters in accordance with applicable classification society standards (ABS, DNV, Lloyd's) and specific vessel structural requirements.
- Surface Preparation & Alignment: The mounting deck ring must be perfectly aligned and securely welded or fastened to a clean, flat, and structurally sound deck plating or tank top surface to ensure a true, unwarped boundary.
- Sealing & Mechanical Verification: Following installation, verify that the cover plate seats evenly on the Buna-N gasket and that the galvanized strong-back and stainless steel T-bolt engage smoothly without binding.
- Debris Inspection: Prior to closing, ensure that all sealing faces, gasket tracks, and mechanical contact surfaces are completely free of weld spatter, debris, rust, or heavy topcoats that could compromise sealing performance.
- Engineering Specifications: Always defer to the vessel designer’s structural blueprint, frame reinforcement guidelines, and governing maritime codes when installing or modifying hull and tank access openings.
Specifications
| Part No | Size | Approx. Weight | Overall Length | Top Length | Throat Width | Throat Height | Base Width | Overall Height | Top Thickness |
|---|---|---|---|---|---|---|---|---|---|
| TH430-24A | 24" (610 mm) Diameter | 118 lbs. | 24" (610 mm) | 26-3/4" (679 mm) | 3/8” (9.5 mm) | 5-7/8" (149 mm) | — | — | — |
