FRP tanks

Tanks made from fiberglass-reinforced plastic are being increasingly used, but a number of failures have occurred. In the United Kingdom 30 catastrophic failures are known to have occurred during the period 1973-1980, and a 1996 report shows that they seem to have been continuing at a similar rate [21J. The following typify the catastrophic failures that have occurred [11]  

These incidents show that, to prevent failures of FRP tanks, we should  

Not repair faults and carry on until their cause is known. 

These rules, of course, apply generally, but they are particularly applicable to FRP tanks. 

Kletz and H. G. Lawley, in A. E. Green (editor), High Risk Safety Technology, Wiley, Chichester, UK, 1982, Chapter 2.1. 

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The utility of the acoustic emission method is also illustrated in the inspection and failure rates of FRP tank given below ... 

Fig. 19.3 was developed to estimate the thickness of FRP Furan tanks. It is based on 500 psi allowable stress and includes a 1/4-in. liner. The wall thickness in FRP tanks normally tapers down from bottom to top for estimating purposes, the thickness should be calculated for the pressure at one-third of the tank height. 

Powdered FRP was manufactured by a machine that have rotating drums with embedded many diamonds. FRP tanks were shredded and powdered to become about 30 micrometers of the average diameter. 

A large number of early fiberglass reinforced plastic (FRP) tanks were constructed in the 1960s for the underground storage of gasoline. The tanks... 

Table 8.3 Properties of unearthed FRP tanks (isophthalic polyester resin SG-10, described in bulletin IP-86 ) with glass reinforcement. Values are averages of several samples...

The tank can be fabricated of rabber lined mild steel, stainless steel, fibre-reinforced plastic (FRP) etc. (whichever is compatible with the chemical) and is mounted on a suitable transport vehicle. It will have arrangement to heat it if necessary. (MSRL/FRP tank will not be heated.)... 

ASTM E1067, Standard Practice for Acoustic Emission Examination of Fiberglass Reinforced Plastic Resin (FRP) Tanks/Vessels, Annual Book of ASTM Standards, Vol. 03.03, American Society for Testing and Materials International, West Conshohocken, Pa., 2004. 

A small quantity of a contaminating compound resulted in equipment failure at a gulf coast chemical plant that had a fiber reinforced plastic (FRP) tank for a process stream that was essentially dilute hydrochloric acid (HCl), a service where the FRP tank would be completely satisfactory. However, this stream contained a small quantity of benzene. Over time the benzene dissolved in the plastic resin, softening it to the point that the tank suddenly failed, sending a wave of HCl into a nearby control room. Fortunately no one was hurt, but the process was down until the tank was replaced. 

Polymer and elastomer coujx>n data must be used in the context of the application. If the application is structural, such as for an FRP tank, mechanical property data are also required. If the application is fully contained, such as an 0-ring, dimensional and hardness change, coupled with visual observations, may provide sufficient information to make a decision. In aU cases, it is useful to discuss the results with a qualified person, such as the supplier of the material. 

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