Flexible Bend Master Articulated

For External Floating Roof Tanks The Flexible Bend Articulated Rigid Pipe Roof Drain System is used to remove rain water from the roof of an External Floating Roof Tank.

The Roof Drain System is designed to remove rain water so as not to put unacceptable loadings on the roof. API 650 Appendix C states that the drain system shall not be smaller than 3 ins (75mm) diameter less than 120 ft or smaller than 4 ins (100 mm) diameter for with a diameter greater than 120ft.

ATECO TANK TECHNOLOGIES can provide this Roof Drain System completely prefabricatedwith an Istallation Manual for final assembly and Installation at site by the customer. Altema ATECO TANK TECHNOLOGIES and ENGINEERING can install the Roof Drain Systems using our own installation crew at a time convenient for the customer.

This Drain System comprises of rigid pipe, normally carbon steel and a number of flexible bend joints. the flexible bend joints incorporate flexible hose material fixed within a sainless steel or galvanised carier frame and are specifically designed for submerged service and the operational requirements of the drain system. it is normal practice to have 4 no flexible bends where the tank diameter is greater than the height and 3 no where the tank diameter is less than the height.

Key Benefits

  • Unlike the swivel joint system, the flexible bends are maintenance free.
  • Load stresses are transferred across the flexible bend not through it.
  • The complete drain system is designed to ensure a continuous slope from roof to shell nozzle and so avoid any water being retainedin the pipe work.
  • The pipework is fitted with support legs, complete with neoprene pads to protect the tank floor when the drain system is in the low position.
  • The drain system is fitted in a fixed position in the tank. This ensures no interference with tank internals, a problem that can occurwith a flexible hose drain system.
  • Rigid pipework ensures no kinking, collapsing, dragging or scraping action across the tank floor something that can be a problem with the flexible hose drain system.
  • There are no piping runs on the underside of the floating roof.

Design Features


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