Tank fabricators

To a large exteat, the vapor pressure of the substance stored determines the shape and, consequently, the type of tank used. The roof shape of a tank may be used to classify the type of tank. This classification is self-explanatory to tank fabricators and erectors. Also important is the tank bottom. 

Total restoration costs approached 35,000. Foundation repairs including resetting the anchor bolts and other support work cost about 5,000. An additional 30,000 was spent to lift the tank, fabricate and install a new tank bottom, and to reinstall and reconnect the pipe the vessel. 

The tank was returned to service receiving a weak acid. The operators observed what appeared to be a rapidly rising liquid level. The level sensing device was actually reading the increasing pneumatic pressure as well as the slowly increasing liquid level as production was routed to the unvented vessel. Within a short time, the tank blew apart at the base. The tank fabricator estimated a failure of this nature could be reached as low as 2.5 psig (17 kPa). 

Low-Pressure Tank Fabrication Specifications Were Not Followed... 

Tank fabricators and tank inspectors check new and repaired welds on floors of low-pressure tanks using soap suds. They commonly use a vacuum box to check tank floor seams. The inspection team coats a short section of weld seam with soapy water. An inspector places a custom-built rectangular box that has a clear window on the top of the soapy weld seam. A specially designed air eductor, which uses compressed air, evacuates the box. If soap bubbles appear in the box, the inspector marks the defective weld for repairs. 

Regardless of which reasoning is preferred, obviously the best answer is to have the tank fabricated with the bottom already sloped, and to avoid the use of two totally dissimilar materials joined together. 

The time required to produce a desired barrier improvement, varies with the type of polymer, its degree of crystallinity and the particular penetrant being considered. For example, a gasoline container or gas tank fabricated of polyethylene generally requires a degree of sulfonation equivalent to about 0.1 mg to 1 mg S03 per cm2. 

Float and tape type level gages should be used to measure liquid level in large field storage tanks. The gege installation kit must be fitted inside the tank by the tank fabricator. 

Low-pressure tank fabrication specifications were not foiiowed... 

The total cost of various types of large zed stora tanks is pven in Fig. 3.4 (97). The cost does not include the cost oi the foundation. Tl otMJt of tanks fabricated from vari-mis materials (IS), fleld-eredted steel tanks 98), and small tanks under 1000 gal (99) has been reported in the literal ure. (See also 26. 27, and 28.) Kgure 3.5 shows the weight of steel afid tlie exist in dollars per ton for large-diameter tanks (97). 

In addition to the normal plastic materials used in tank construction, stainless steel can be used for EN tanks. This is possible only with the use of anodic passivation, which employs an electrical bias applied to the steel to prevent reduction of nickel ions on the steel. By using steel tanks, fabricators avoid the frequent stripping of plastic tanks required due to the slow plate-out of nickel on rough surfaces and localized hot spots. 

Doyle Roth Manu cturing Co., Inc. / Eastern Tank Fabricators Dry Link, Inc. 

Eagle Stainless Container Co. EagleBurgmann Mechanical Seals Eastern Tank Fabricators ecom instruments inc Edwards EGC Plastics Emery Winslow Scale Co. Enardo Enerquip LLC... 

Core tank scrap material from HRE-2 core-tank fabrication see Article 5-8.2. 

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