Field Erected Tanks New Construction

Link to pictures of past jobs.

     Tank Options

Tank Roof Options

Tank Floor Options

Tank Roof Access Options

Tank Roof Platforms Options

Agitator Supports

Tank Baffles

Tank Nozzle Options

Tank Manways

Anchor Chairs

Tank Roof Options

  • Self Supporting Cone Roofs

  • Structure Supported Cone Roof with Internal Floating Roof

  • Self Supporting Cone Roof with Rafters

  • Structure Supported Cone Roof with Internal Rafters & Columns

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Cone Roofs

Self supporting cone roof tanks. Notice the steep roof pitch.  The steep roofs are for the tanks to better deal with the snow load we see in Canada. Snow slides off of the tank instead of building up on top of the tank.

 

Self supporting coned roofs with internal floating roofs (IFR). These type of tanks are popular in Canada because the cone roof keeps the snow out. Notice the vents on the side of the tank. These are the vents between the internal floating roof and the cone roof.

 

 

Self supporting coned roofs with External Rafters. These type of tanks are used on larger tanks where a Self Supported Cone is not possible by itself. Rafters can be either internal or external. External rafters are usually used on tanks that will have an internal lining. The rafters are put on the outside so so Coating Applicators do not have to deal with all the sharp edges.

 

Supported cone roof with Internal Rafters & Columns is a common design in North America. It is found on larger tanks where self supported cones are not possible. The columns are not welded to the floor to allow for thermal expansion of the tank.

 

Supported cone roof with External Rafters & Columns is a common design in North America. It is found on larger tanks where self supported cones are not possible. The columns are not welded to the floor to allow for thermal expansion of the tank.

Domed & Umbrella Roofs

Self Supporting Domed & Umbrella Roof As tanks get larger using the API codes it is often less expensive to build a self supporting domed or umbrella roof as in the above picture.  A sphere is the most efficient container to resist pressure. Since a Dome roof is closer to a sphere than a cone the API codes give the designer credit for using a dome as opposed to a cone. In other words we can often build a tank with a Dome roof constructed out of thinner material than a cone.

Geodesic Aluminum Dome Roof covers and structures feature all-aluminum construction. Geodesic domes are lightweight, corrosion resistant, and virtually maintenance-free, which translates to longer life and lower costs. They don't rust like steel, they don't degrade with ultraviolet light like fiberglass, and they don't spall like concrete.


Floating Roofs

 

External Floating Roof (EFR) tank.

Catwalks, Platforms, Stairs & Ladders

AGI uses Process Industry Practices publications where we can to help design our catwalks, platforms, stairs and ladders.

 

The ladder is the most economical way to access the top of a tank. It is also the least safest. Notice the rest platforms. Provincial safety regulations govern how frequently rest platforms are required if fall prevention is not used. Provincial safety regulations are not the same from province to province so make sure your designer or tank fabricator knows what the regulations are. Also notice the cage on the ladders. Provincial safety regulations govern the height of these cages as well. 
Spiral stairs with Rest Platform is the most common way to access the top of a tank.  Notice the rest platforms. Provincial safety regulations govern how frequently rest platforms are required. Provincial safety regulations are not the same from province to province so make sure your designer or tank fabricator knows what the regulations are in the province your tank is located.  

Radial Stairs with rest platforms is the most expensive and safest way to access the top of your tank. Many clients specify radial stairs because an operator would be stepping away from the tank if it was on fire. Instead of around the tank with spiral stairs.

 

Joining Catwalks  Tanks are often joined together via catwalks. Joining tanks via catwalks provides an alternate method of escape in the case of a fire.  Notice the different catwalk designs. The distance spanned determines the design AGI would select. Catwalk designs are similar to bridge designs.

Tank Manways

API 12F Manway Cleanout API 12f Cleanout Manways is the most economical way to access the inside of your tank. This manway should only be used on shop built tanks.
API 650 Round Side Manway API 650 Shell Manways is the most economical way to access the inside of your tank. API 650 has designs for shell manways from 20" to 36". Please note that these manway flanges are fabricated flanges not ANSI B16.5 flanges. The picture to the side shows a tomb stone repad around the manway and a davit on the manway lid.
Flush Cleanout Flush Cleanout Manway is a more expensive way to access the inside of your tank. The advantage to the flush type clean out is that it is flush to the floor. Your tank will be easier to clean with such a manway. This manway is more expensive because the API 650 code requires this manway to be built on the shell sheet and Post Weld Heat Treated as one unit. The code also requires this assembly to be examined via Magnetic Particle after PWHT. The reasoning behind this is that the shell to floor joint is a high stress area in a tank.

Tank Anchors

Anchor Chair Anchor Chairs are designed per AISI Steel Plate Engineering Data, Volume 2, Part 5. Anchor chairs keep floors from uplifting due to internal pressure and the tank from tipping over due to wind and seismic forces.
   

AGI    Biggar, Saskatchewan    ph: 1-800-746 -6646   fax: 1-306-948-5263  Email: info@envirotank.com  Web: www.Envirotank.com