Physical tests visual inspection

This is the more normal test situation. For processes where prooftesting the final trip or control element cannot be made available (such as testing a furnace shutdown system), the maintenance mechanics perform a prooftest as described above (complete loop test) with the exception of testing the final trip or control element. All components in the loop including the final element are visually inspected for physical condition. Maintenance takes test credit for the portion of the loop prooftested. 

Nondestructive Testing. Nondestructive testing (NDT) is far more economical than destructive test methods, and every assembly can be tested if desired. Several nondestructive test methods are used to check the appearance and quality of structures made with adhesives or sealants. The main methods are simple ones such as visual inspection, tap, proof, and more advanced physical monitoring such as ultrasonic or radiographic inspection. The most difficult defects to find are those related to improper curing and surface treatments. Therefore, great care and control must be exercised in surface preparation procedures and shop cleanliness. 

When the computer system arrives, the shipment should be checked by the user for completeness. It should be confirmed that the equipment ordered is what was in fact received. Besides the equipment hardware, other items should be checked, for example correct cables, other accessories and documentation. A visual inspection of the entire hardware should follow to detect any physical damage. For more complex instrumentation, for example, when multiple computers are connected to a network, wiring diagrams should be produced, if not supplied by the vendor. Distance between the computers and peripherals such as printers and analytical equipment must be within manufacturer s specifications. For example, long low-voltage electrical lines from analytical equipment to computers are vulnerable to electromagnetic interference. This may result in inaccurate input data to the computer. In addition, electrical lines should be shielded if motors or fluorescent light sources are nearby. At the end of the installation of the hardware an electrical test of all computer modules and systems should follow. 

A serious problem encountered with the application of polynomial curvefitting is the fundamental decision as to which degree of polynomial is best. Visual inspection of the experimental data may indicate that a straight line is not appropriate. It may not be immediately apparent, unless theory dictates otherwise, whether say, a quadratic or cubic equation should be employed to model the data. As the number of terms in the polynomial is increased, the correlation between the experimental data and the fitted curve will also increase. In the limit, when the number of terms is one less than the number of the data points the correlation will be imity, i.e. the curve will pass through every point. Such a polynomial, however, may have no physical significance. In practice, statistical tests, based on the use of the F-ratio, can be employed to examine the significance of terms added to a polynomial and to indicate whether observed increases in the correlation coefficient are statistically significant. 

In the various other solvents employed the specimens were visually inspected and submitted for physical testing in an effort to discern changes in tensile or pulling strength according to a modification of the procedure reported by Schnell (16). These results are shown in Table III. 

There is a United States Federal Specification dated 1976 that describes a physical test for vial integrity consisting of suspending the vials upside down at room temperature for 2 h and then at 49 C for 4 b. Evidence of leakage may be by weight or by visual inspection. This test is of somewhat, doubtful relevance to microbiological penetration. 

Screening for blood Chemical testing for blood or traces of blood is often needed to provide physical evidence in cases in which direct visual inspection is not a decisive proof. 

Physical tests, such as impact and tensile, were not carried out since it was considered unnecessary if the visual inspection was satisfactory. 

Unlike coatings made from thermoplastic powders which require only a visual inspection to see whether the coating is satisfactory, thermosetting powder coatings require additional examination to determine whether the coating has achieved its full physical properties. Simple mechanical tests may be used, as is the practice with conventional paint finishes, but, particularly for epoxy powder coatings, it is normal to use chemical resistance as a criterion for suitability. A common method is to swab the coating continuously for 30 seconds with a cotton wool pad soaked in methyl isobutyl ketone. Any deterioration of... 

These techniques involve the analysis of the changes in the chemical and physical properties of a molded specimen as a function of temperature. They are not generally used for production or quality control but are quite useful in resolving problems that could be the result of insufficient cure and that are not readily detected by the more common visual or chemical tests. There is a rule-of-thumb test procedure that is a fairly reliable cure test, and it is based upon a visual inspection of the molded article for obvious defects such as... 

Leeds Northrup, FA No Q3440, S/N, 1026920. After completion of the solar test, lower the temp of the chamber to RT (ca 72° F) and inspect the sample visually for any possible physical damage. 

NFPA 25 states the frequency of a procedure at the particular element (inspect, test, or maintain) and the method by which the procedure is carried out at that element. For purposes of NFPA 25, inspection is a visual examination, testing is a physical check of the component, and maintenance k work performed on a component to keep it operable. 

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