Acceptance of internal floating disk

Saw it online; those who are not familiar with it can take a look! An internal floating disk in a storage tank is an energy-saving and environmentally friendly device that rests on the surface of the liquid, rising and falling with the level of the liquid in the tank thanks to buoyancy. To reduce the volatilization of the medium in the storage tank, minimize losses and save energy, as well as to protect the environment, an internal floating disk is installed inside the tank. Storage tanks utilize floating disks to seal the stored medium and reduce its temperature, thereby saving energy and protecting the environment. Quality assurance measures: 8.1 A strict handover and acceptance system must be implemented. Before construction, the foundation of the oil tank should be inspected jointly by the civil engineering team, the installation team, and the owner. Key parameters such as the center coordinates, center elevation, surface irregularities, and surface curvature must meet the requirements specified in the design specifications to ensure that the bottom plate is laid evenly. 8.2 Welding work at the site must be carefully managed; welding materials must come with factory certification, and welding rods should be baked, managed, distributed, and collected by designated personnel. The welding procedures must be strictly followed, and welders must hold valid operation certificates. 8.3 If the ring plates are deformed, they should be corrected before installation, with their curvature meeting the design requirements – special attention should be paid to the vertical edges of each ring plate. 8.4 The radial and circumferential ribs of the top cover must conform to the design specifications; if the top plate is deformed, it should be corrected before being installed. 8.5 Inspection rules must be followed to ensure high-quality inspections. The measuring instruments used during construction must be calibrated in accordance with the relevant management regulations, and only those that pass regular inspections may be used. 8.6 A strict material inspection system is necessary; all steel materials, accessories, and welding materials used must meet the design requirements and come with product quality certificates. The A, B, and C level inspection systems must be properly implemented to ensure good project quality and successful project completion.

No standards above the industry level have been found; generally, the design team prepares a \"Technical Specification Sheet\". I’ll send you one to try. QW023-B02 Technical Specification Sheet File Number: 07318D-240-BFP/Spec/Clarification. Total of 6 pages, Page 1. Technical Specification Sheet for Stainless Steel Inner Floating Roof. Prepared by, Reviewed by, Approved by: QW023-B02. Technical Specification Sheet for Stainless Steel Inner Floating Roof. File Number: 07318D-240-BFP/Spec/Clarification. Total of 6 pages, Page 2. This technical specification sheet applies only to the minimum requirements for the design, manufacturing, inspection, packaging, and transportation of stainless steel inner floating roof units for newly constructed 30,000 m3 inner floating roof storage tanks in “-----”. This technical specification relates to internal floating roof units. The manufacturer shall design, manufacture, inspect, and accept the equipment in accordance with the parameters specified in the internal floating roof device specification sheet, following relevant standard specifications, and provide excellent service. I. Main standards and specifications: The design, manufacture, inspection, and acceptance of prefabricated stainless steel internal floating roofs (including on-site sealing tests and water filling tests for floating roof tanks) must comply with the requirements of the latest versions of the following standards and specifications. API650 “Welded Steel Oil Tanks” – Appendix H; GB50128-2005 “Code for Construction and Acceptance of Vertical Cylindrical Steel Storage Tanks”; GB50341-2003 “Code for Design of Vertical Cylindrical Welded Steel Oil Tanks”; SH3046-93 “Code for Design of Vertical Cylindrical Welded Steel Storage Tanks in Petrochemical Industries”; GB13348 “Code for Static Electricity Safety of Liquid Petroleum Products”; GB/T 4237-1992 “Hot-Rolled Stainless Steel Sheets”; GB/T14975-94 “Seamless Stainless Steel Tubes for Structural Use”; HG/T2809-96 “Rubber for Soft-Sealing Devices in Floating Roof Tanks”; GB/T8165-1997 “Stainless Steel Composite Sheets and Strips”; GB/T5780 Hex Head Bolts – Class C; GB/T3098 Mechanical Properties of Fasteners – Nuts. II. Technical Requirements: 1. To meet the requirements for dual sealing of internal floating roofs, these roofs adopt a frame structure, with a dual-edge design at their perimeters. The buoyancy provided by the floating elements between these edges must be sufficient to withstand the static load under dual-sealing conditions as well as the dynamic friction forces during operation. The designed buoyancy of the internal floating roof should be no less than twice its own weight plus the friction force between the seal and the tank wall. In both the supported and floating conditions, any part of the inner floating disk shall be able to withstand a concentrated dynamic load of not less than 2.2 kN. The buoyancy element structure adopts a rolled plate welding design. 2. The buoyancy elements of the internal floating roof must meet the airtightness requirements. The buoyancy element itself, as well as the connection structure between the buoyancy element and other components, must be able to withstand the vapor-liquid shock generated during maximum liquid inflow. After any two buoy tanks leak, the internal floating roof should still be able to float on the liquid surface without causing additional hazards. QW023-B02 Stainless Steel Internal Floating Roof – Technical Specification Sheet. File number: 07318D-240-BFP/Spec 06303D2-301-FF/Spec. Total of 6 pages, Page 3. 3. The outer peripheral plates of the internal floating roof, the roof supports, and all the openings on the roof must be at least 150 mm above the liquid level, while the depth of immersion in the liquid should not be less than 100 mm. 4. All metal components on the internal floating roof shall be electrically connected to each other, and connected to external grounding elements of the tank through the tank wall. When the electrostatic extraction wires are connected to the fixed disk, there must be no less than 2 sets, and they should be evenly distributed. When selecting wires, factors such as strength, flexibility, resistance, corrosion resistance, the reliability of connections, and service life should be taken into account. 5. When pillars, guide devices, etc. pass through the floating pad, reliable sealing passing devices should be installed. 6. Fixed floating disk supports should be installed on the internal floating roof. When the inner floating disk is at its lowest support height, the floating disk and the components below it must not collide with each other ； When the floating disc is at the maximum designed liquid level, the strut should not collide with the fixed disc. 7. The internal floating roof struts and tray accessories (such as reinforcement plates and buoy end plates) should be designed to support the total static load of the internal floating tray (including all components such as seals and accessories), as well as a uniformly distributed load of 0.6 kPa on the trays when the roof struts settle onto the bottom of the tank. The effect of uneven support settlement should also be taken into account. 8. Continuous fillet welding shall be used within a 300 mm range around the lower surface of the welded internal floating roof strut. The floating roof struts themselves, as well as the connection structures between them and other components, must be able to withstand the vapor-liquid shock generated during maximum liquid inflow. 9. The height of the pillar is 1.8 m, and an oil-resistant rubber pad is installed at the lower end of the pillar to protect the anti-corrosion layer on the bottom of the tank. The material of the protective pad should not contaminate the storage medium. The pillars shall not have butted welds. 10. A tongue-shaped sealing device should be installed at the annular gap between the outer edge of the internal floating roof and the tank wall. The sealing device should be able to compensate for deviations in the circumferential gap size of ±100 mm, and it must have good sealing performance. 11. The specifications of the sealing strip for sealing are 310×12×5. The material is nitrile rubber. 12. The material should meet requirements such as temperature resistance, wear resistance, corrosion resistance, flame retardancy, impermeability, aging resistance, and compatibility with the medium. 13. The circumferential joints shall be firmly connected, leak-free, with an overlap width of not less than 75 mm. 14. Automatic vent valves shall be installed on the floating deck, and their quantity and flow area shall be determined based on the maximum flow rate during oil receipt and dispatch. When the floating disc is in the supported position, the vent valve should be able to open automatically ； When the floating disc is in a floating state, the ventilation valve should be able to close automatically and should seal well. 15. The opening height of the automatic vent valve’s cover should be such that the flow area between the cover and the valve body is greater than the flow area provided by the diameter of the valve body. The valve stem made of steel pipe should have both ends sealed off ； Either the upper end is closed off, or a notch is provided at the lower end to allow the accumulation of fluid to be drained. 16. Guiding devices should be installed on the internal floating roof. The guide device at the location where it passes through the floating pad should be properly sealed. 17. The service life of all components of the internal floating disk, including seals, shall be no less than 10 years. QW023-B02 Stainless Steel Inner Floating Disk – Technical Specification Sheet. File number: 07318D-240-BFP/Specs/Instructions. Total of 6 pages. Page 4. 18. The specifications, dimensions, thicknesses, and profile characteristics of all components of the floating disk, as well as the methods of connecting these components, must comply with relevant requirements; it is not allowed to reduce the specifications or alter the connection methods. 19. The material, specifications, and quantity of the floating roof connectors shall meet the requirements of the standards; it is not allowed to use lower specifications, different materials, or reduce the quantity. 20. Specifications, welding, and pressure testing of the buoy (1) Specifications of the buoy (diameter, thickness): The diameter of the buoy is φ200 mm; the ellipticity of the buoy’s outer diameter should be controlled within 1%, with a maximum value of 2.0 mm. (2) For the welding of the longitudinal seams in the floats, weld wires of the same material should be used, argon arc welding should be employed for sealing the bottom of the welds, and a fully penetrated weld structure should be achieved. The welds should be smooth, with minimal variation in the wave height of the weld surface

Test plan for the lifting of aluminum floating disks by filling with water: 1. First, connect the water filling pipeline to the storage tank and secure attachments such as manholes, then wait for the water to be filled in. 2. The water used for testing should be clean, with a temperature of no less than 5 degrees. 3. The initial water filling rate should not exceed 1 cubic meter per second; the water flow rate can be increased after the floating disc rises. 4. Once the floating disk rises to 3 meters, stop filling water and maintain the pressure for 2 hours. 5. After the test is completed, drain the water. Once all the water in the storage tank has been removed, the manhole cover can be opened, and inspections should be carried out item by item in accordance with the check items specified in the aluminum floating disk installation and acceptance certificate, with records kept of these inspections. Certificate of Installation and Acceptance for Internal Floating Roof
Name of the specific project:
Serial number | Inspection item | Acceptance standard | Actual measurement results | Remarks
1 | Levelness of the internal floating roof | Maximum deviation not exceeding 10 mm; inspection is carried out at the lower ends of each pillar sleeve | | |
2 | Contact between auxiliary plates and edge components | No light leakage when illuminated with a flashlight | | |
3 | Verticality of pillars | Deviation amount less than 10 mm | | |
4 | Water filling test | The internal floating roof rises and falls smoothly during water filling, without any tilting or jamming, and the frame shows no abnormal deformation; water filling temperature is above 5 degrees, and the system is kept at the highest operating liquid level for 2 hours