Rafter Supported Cone Roof

Supported at tank shell and load is transferred to tank periphery.

Rafter supported cone roof.

Good access exists to tank for equipment and materials. The columns are not welded to the floor to allow for thermal expansion of the tank. Roof is designed as a supported cone roof. Tank is clean gas and lead free and ready for hot work.

Fabricate install new supported cone roof the screening estimates are based upon the following assumptions. Purlins as shown in sample photos below are installed for rafter support. This roof ends in an octagonal hip. Supported cone roof with external rafters columns is a common design in north america.

A collar tie is a horizontal roof rafter compression connector that is located in the uppermost third of the span of a pair of opposed sloped or gable roof rafters. Frame or truss supported. By upper third here we mean one third of the length of the rafter from ridge to top plate. Under the midsections of the rafters are purlins which support the common rafters and are supported by principal rafters.

A double roof using a norman truss common rafters supported by principal rafters top chords in this case and an unusual extra layer of common rafters on the lower half to form a gallerie. Doorsheet is a minimum of 8 high x 8 6 wide. Of all the cylindrical tanks the cone roof tank is the most popular for storing less volatile liquids such as heavy or light oil. Maximum rafter span of 16 feet.

No hours are included for a dedicated fire safety watch. The spans in this table are based on a maximum supported rafter span of 16 feet where the supported span is the total horizontal distance spanned by the roof rafters divided in half not the diagonal distance or the length of the rafter. This table is simply a sample and may not be valid for your region. The purlins are supported by vertical or slightly angled bracing.

In finding this location we do not count the additional length of the rafter that supports the roof eaves overhang or soffit. Roof plate shall be designed as continuous beam with uniform load comprising of roof live load and self weight of roof plate. Supported cone roof with internal rafters columns is a common design in north america. This roof ends in an octagonal hip.

Ste makes the cone roof tanks in three type.