Our D400 double‑triangular cover is fully certified to BS EN 124:2015 Class D400, tested to 400 kN (40 t) static loads for main roads and carriageways. It offers a precise 600 mm clear opening within a 100 mm deep circular frame, seamlessly integrating with standard chambers and surfacing. Crafted from high‑grade ductile iron (EN GJS 400‑15), the cover and frame resist corrosion and fatigue under heavy cyclic loads. The patented double‑triangular, three‑point suspension non‑rock design prevents rattling and debris ingress, ensuring long‑term stability and quiet operation. A slip‑resistant diamond tread pattern enhances safety in wet and dry conditions. Finished with black bitumen coating and backed by BSI Kitemark certification, the frame incorporates anti‑movement technology to secure bedding material and maintain flush seating over time. Available in hinged (135°) or lift‑out configurations with ergonomic keyholes for compliant one‑man lifts, it simplifies maintenance and supports rapid access.

Technical Specifications

Key Features

Robust Load Class

Engineered and tested to BS EN 124:2015 D400 standards, sustaining 400 kN loads for highways and busy urban environments.

Precision Fit

A precise 600 mm diameter aperture in a 100 mm deep circular frame accommodates standard chambers, ensuring flush installation and minimal surfacing build‑up.

Premium Ductile Iron

Manufactured from EN GJS 400‑15 ductile iron, the cover and frame resist corrosion, cracking, and fatigue under cyclic loading.

Non‑Rock Stability

Unique double‑triangular three‑point suspension prevents cover movement and noise, enhancing structural stability and public comfort.

Slip‑Resistant Surface

Diamond tread pattern meets slip‑resistance requirements, providing enhanced grip for pedestrians and vehicles in all weather conditions.

Secure Bedding

Anti‑movement frame technology locks bedding material in place, preserving road integrity and preventing subsidence over time.

Certified Quality

BSI Kitemark certified and black‑bitumen coated as standard, with optional epoxy or powder‑coat finishes to suit project aesthetics.

Ergonomic Handling

Available hinged (135° opening for safety) or lift‑out design; strategically placed keyholes allow compliant one‑man lifting under EN 13155 regulations.

Applications

• Main Roads & Carriageways: Engineered for heavy traffic zones and emergency routes.

• Industrial & Distribution Sites: Withstands forklift and delivery vehicle loads.

• Commercial Car Parks: Delivers strength and safety for public parking areas.

• Urban Streets & Plazas: Flush integration preserves aesthetic continuity.

Installation & Maintenance

1. Drop‑In Frame: Place the 100 mm deep frame into a prepared round aperture with minimal bedding mortar.

2. Hinged Models: Secure cover with integrated hinges—opening locks at 135° for safe one‑man operation.

3. Lift‑Out Variants: Use standard D400 lifting keys in ergonomic keyholes for fast, compliant removal.

4. Maintenance: Inspect periodically; reapply bitumen touch‑up or chosen finish to extend service life.

Why Choose Our D400 Double Triangular Cover?

Combining industry‑leading non‑rock technology, slip‑resistant surfaces, and ductile‑iron durability, our cover ensures long‑term infrastructure reliability and safety. Backed by BSI Kitemark certification and global supply support, it represents a future‑proof investment for trafficked environments. For custom badging, specialized coatings, or project-specific technical assistance, contact our engineering team for bespoke solutions and rapid delivery.

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