RTP Design vs. API 12B

Tank Connection Affiliate Group... "Off the Charts with Performance!"

Once you understand the facts on today's technology and precision storage products available, the tank selection process in dry bulk and liquid storage will narrow to one of six choices: RTP Bolted Construction, FP (flat panel), Field-Weld, Shop-Weld, Hybrid or Concrete Construction. API 12B (flanged panel) and seal welded bolted construction have become outdated designs, relics of the past.

The Tank Connection Affiliate Group is recognized as the new domestic leaders in storage tank designs and integrated storage systems. All storage containment developed by the TCA Group fulfills today's storage requirements as prescribed by engineers around the world... high quality, low maintenance, long life and cost efficient.

The TC Affiliate Group is a family of companies that specialize in dry bulk and liquid storage applications. We remain the only company worldwide that designs, manufactures and installs all four types of steel storage systems. This includes Bolted RTP (rolled, tapered panel), Field-Weld, Shop-Weld and Hybrid Tank Construction.

Because we listen to our customers and develop products to match today's requirements, our growth over the last five years has been "off the charts." We have invested in the future of storage containment worldwide by investing in people. Our affiliate group has over 1800 years of combined storage tank/silo experience. In review of our employee profiles, you will find that the TC Affiliate Group are the recognized experts in FP, RTP, API 12B, field-weld and hybrid tank construction. This experience level is tied to tank design, tank specification development, tank accessory development, tank fabrication, field installation, and always "golden rule" customer service. It is a pleasure to serve an industry with products that remain unmatched in the industry. Our products and our people show our commitment to serve our customers.

The History & Facts - API 12B (American Petroleum Institute) Bolted Tanks

API 12B fabrication evolved from the oil patch market in the early 1900's. This standard was developed for a bolted flat bottom tank that would store crude oil. The tank sizes were small (~ 100 to 10,000 barrels in size) and were shipped to the field to be erected by oil field workers. The seal between panels utilized a buna nitrile gasket material. Flanging dies were utilized to create an exterior horizontal flange (chime) connection (see figure 1.1.), which allowed the panels to be easily assembled in the field using a gin pole and scaffold system. The flanging dies were designed for forming light gauge material thicknesses ranging from 12 gauge up to 3/16" plate. Eventually these tanks evolved to include small hopper bottom designs for the storage of grain and other bulk materials.

As time passed, the market required larger tank sizes, which historically had been served by field-weld and concrete construction. As a less expensive design, the API flanging dies were used and the material thicknesses were increased to 1/4" plate. An erector's set of stiffeners were added to meet basic design parameters (i.e., wind, seismic, etc.). The process continued to evolve with more and more stiffeners added to the tank skirt and sidewall areas, similar to today's corrugated grain tanks. Dry bulk and liquid storage tanks continued to grow in size and capacity. This is when the design failure in API 12B fabrication started to appear. When standard tank design parameters required heavier plate thicknesses, the flanging dies designed for 3/16" material were utilized on 1/4" and 5/16" plate material. The results were exterior flange connections (chimes) that did not break at 90 degrees and would not seal (see figure 2.1).

The Goal was clear...

Upon review of the TCA Group employee profiles, you will find that TC is a collection of the recognized experts in API 12B, field-weld, RTP, FP, shop-weld and hybrid tank fabrication. The Tank Connection goal was to take the FP (flat panel) tank design that was outdating the API 12B tank in the liquid market and establish it in the dry bulk market with industrial process standards. The FP (flat panel) tank designs (i.e., Aquastore, Permastore, Fusion, etc.) at one time were the best bolted tank designs in the liquid markets with field performance that far exceeded the API 12B specification for liquid storage. The FP tank designs will always outperform the API 12B tank in every performance rating.

• No leaks
• No problematic exterior flange connection
• Improved field construction techniques

The Solution identified...

The FP (flat panel designs could be improved with a precision taper and mitered corner connection (see figure 3.1), "state-of-the-art" powder coating technology and further development of a synchronized field jacking process that would improve quality and safety in the field, while keeping field crews on the ground. Needless to say, this field construction process would become the #1 rated process for tank construction within a short period of time.

Tank Connection Solution:

• Eliminate the API exterior flange, which equated to removing the leak source
• Increase plate thickness (simulate field-weld tank construction for industrial process applications) without adding an "erector's set" of stiffeners
• Utilize Fusion 5000 FBE™ powder coat system designed by Akzo Nobel for complete coating wrap-around on steel for "long life" storage
• Develop a safe field construction process utilizing "state-of-the-art" technology
• Utilize a field-weld hopper connection approach in dry bulk storage
• Align vertical seams (for symmetrical design)
• Utilize length x height panel equation - similar to field-weld construction

The result was an RTP (rolled, tapered panel) design that could address and eliminate all the problems associated with API 12B flanged panel tank construction.

The Outcome...

Tank Connection now crosses the five year mark and our "dry bulk" industrial storage business in North America exceeds all other bolted tank manufacturers. TC, with its precision RTP tank design, has restored customer confidence in bolted tank construction. TC's international market demand for RTP construction in liquid and dry bulk applications remain "OFF THE CHARTS". Tank Connection maintains three manufacturing facilities that serve the storage tank industry, with an additional 85,000 square foot facility under construction for RTP and Hybrid tank construction. Our commitment for quality containment that is unmatched in field performance has made us #1 in storage tanks and integrated storage systems.

---

Tank Connection, LLC
www.tankconnection.com
1801 South 21st Street Parsons, Kansas 67357
Phone: 620.423.3010    Fax: 3999