Installation and Inspection Notes for Marine Quick-Opening Watertight Doors

1. Pre-installation Notes

• Verify that the door model, specifications and classification society certificates (CCS/BV/LR/DNV/NK, etc.) are consistent with the design drawings.
• Check that the door frame and panel are free of deformation, collision damage, and the coating is intact; ensure the sealing gasket is undamaged.
• Confirm that the opening size, reinforcement structure and welding groove are constructed in accordance with the hull structure requirements.

2. Installation Process

• Position the door frame vertically and horizontally, and control the diagonal error within the allowable range.
• Adopt continuous/full welding; spot welding and incomplete welding are not allowed. The welds shall be full without air holes or cracks.
• Clean the welding slag after welding and apply anti-corrosion coating to avoid corrosion.
• Install hinges, locking mechanisms and connecting shafts to ensure smooth operation without jamming.
• Adjust the quick-opening mechanism (handle/cam/pressure wheel) in place to ensure even compression after closing the door.
• The sealing gasket shall not be stretched or distorted, and shall be installed flat with tight joints.

3. Quality Inspection Key Points

3.1 Visual Inspection

• The door panel and frame are free of deformation, and the surface coating is intact.
• The welds are flat and free of defects.
• Fasteners are complete and securely locked.

3.2 Operation Function Inspection

• Quick opening/closing can be achieved with a single handle, and the operating force is moderate.
• The locking points are pressed synchronously without looseness or deviation.
• There are no obvious gaps after closing the door.

3.3 Watertight Test

• Conduct a hose test or pneumatic test in accordance with the requirements of the classification society.
• No leakage at the door seams, surrounding areas and welding joints.

3.4 Structure and Safety Inspection

• The door opening angle meets the usage requirements and does not interfere with surrounding equipment.
• Emergency opening and limiting devices are effective (if equipped).
• Nameplates, certificates and marks are complete and clear.

4. Acceptance and Handover

• Provide complete product certificates, material certificates and welding records.
• Sign the acceptance document after the watertight test is qualified.
• Clean the door body and lubricate the moving parts before delivery for use.