ASME STP-PT-021:2008 pdf free download

ASME STP-PT-021:2008 pdf free download.NON DESTRUCTIVE TESTING AND EVALUATION METHODS FOR COMPOSITE HYDROGEN TANKS.
Transmit and Receive channels. Figure 9. show the wavelet form used by the Modulus Analyzer. In this case both waves are same as part of a functional check of the tone generator.
The Modulus Analyzer is an electronic instrument the size of a portable oscilloscope and the scanning head fits in the palm of the hand, The scanning head contains a Transmit/Receiver sensor pair. The Analyzer measures the velocity and amplitude of the received wave in a standard sample and displays them as a percentage. The instrument is calibrated by setting them to 100%. Those suene variables are then detected in the part to he assessed and the percentages displayed. This gives a very simple. straightforward relative measurement of the modulus of the material between the T’R transducer pair.
1.3 Lincoln Composites Pressure Vessels
The Lincoln Composites vessels represent a class or type manufactured for aulomo(ivc fuel purposes. There the plastic liner has little structural strength, so the carhonglassepoxy composite material beam the load in these completely overwrapped vessels. The NDE driver is to ascertain the integrity of the composite materiaL In both types of PV. there is a need to reduce manufacturing cost by reducing the number of vessels selected for destructive testing, as well as to develop technologically and economically feasible methods that could be used verify the integrity while in service. Simple. robust and low cost methods are the keys to implementation and this was kept in mind for the practical value to the industry. Pressure vessels were tested under this project also in order to reduce product development time. If Modal AF. could be used to distinguish pressure vessels made differently and predict which would base the higher burst, then this would be accomplished. It Modal AF. could distinguish between vessel quality, then not as many would have to be sacrificed to burst testing. thereby increasing the quantity that could be sold while increasing product assurance. This would improve QC and lower manufacturing overhead costs.
The Lincoln Composites PVs were built with a hybrid of carbon and fiberglass fibers wound with an epoxy resin over a plastic liner. Dimensions were 3-feet long and IX inches in diameter, An example is shown in Figure 10. Failure at burst pressure was controlled by the composite. Damaged and undamaged vessels were burst, with the damaged vessels representing extreme QC cases. The results. in brief, were that Lincoln Composites has established very good manufacturing practices that enable it to create nearly identical vessels on a routine basis. However, this statement is based on a very limited number of tests. Only by routinely monitoring eser hydrotest oser an extended period of üme would the statistics become meaningful and then sampling theory could be used to further reduce costs at a high level of assurance and the need for burst tests be reduced to a minimum. The cost tradeoffs of implementing such a program would also have to be thoroughly scrutinized. As far as the Modal AE technique is concerned, the presence of damage was readily identified and located.