The tensile-strength test is inherently fruitless; at the time of the process of gathering material, the sample is ruined. Though this is not an issue when a plentiful sample of the material exists, nondestructive methods are better for materials that are expensive or arduous to create or that have been formed into completed or semifinished products.
Liquids
One common nondestructive technique, employed to detect surface breaks and imperfections in samples, employs a penetrating fluid, which needs to be brightly coloured or fluorescent. After being rubbed on the surface of the metal and left to sink into any surface breaks, the fluid is removed, leaving readily revealed imperfections and imperfections. A similar test, better for nonmetals, takes an electrically charged liquid pasted on the material surface. After the extra liquid is removed, a dry powder of opposite charge is sprayed on the surface of the sample and attracted to the flaws. Neither of these methods, however, can locate internal imperfections.
Radiation
Internal, like external flaws, can be found by X-ray or gamma-ray technologies in which the radiation passes through the sample and impinges on an appropriate photographic film. Occasionally, it can be possible to nominate the X rays toward a single plane in the material, creating a three-dimensional description of the flaw shape as well as its position.
Sound
Ultrasonic inspection of parts involves transmission of sound waves out of human hearing range within the test material. By the reflection method, a sound wave is sent over one end of the sample, reflected from the far side, then signalled onto a receiver located at the first side. Upon impinging on a weakness or weak point in the test sample, the signal is reflected and its signal altered. The actual delay is then a sign of the location of the flaw; a map of the test material can then be generated to show the point and shape of the cracks. By the through-transmission process, the transmitter and receiver need to be located at opposite ends of the material; interruptions in the movement of sound waves are used to locate and measure imperfections. Usually a water medium is used in which transmitter, sample, and receiver are immersed.
Magnetism
As the magnetic elements of a sample are strongly formed by its overall shape, magnetic processes can be used to isolate the location and approximate dimensions of weaknesses and imperfections. By magnetic testing, an item is used that consists of a large length of wire through which flows a steady alternating current (primary coil). Nested inside this larger object is a smaller coil (the secondary coil), to which is attached an electrical measuring tool. The steady current in the initial coil causes electrical current to flow through the secondary coil by way of the method of induction. If an iron rod is placed into the secondary coil, sharp changes in the second current should isolate marks in the piece. This process only locates differences within sections on the length of a piece and does not detect longer or continued defects that readily. A parallel skill, using eddy currents induced by a primary coil, also can be used to detect flaws and weaknesses. A steady current is induced in the test object. Marks that lie in the transmission of the current make for resistance of the test piece; this adaptation may be measured by suitable methods.
Infrared
Infrared methods have sometimes been employed to detect material continuity in involved construction situations. In testing the value of adhesive joins between the sandwich core and facing sheets with a standard sandwich structure item such as plywood, for example, heat is used in the surface of the sandwich skin piece. When bond lines are found to be continuous, those core samples provide a heat signature within the surface material, and the localised temperatures of the skin should appear steadily on the bond lines. When the bond line is inadequate, missing, or in error, however, the local temperature should not fall. Infrared photography of the area shall then demonstrate the placement and shape of the failing adhesive. Another such method uses thermal coatings that change appearance when reaching a determined temperature.
Conclusively, nondestructive processes also are now being shown to allow a whole determination of the mechanical properties of a test object. Ultrasonics and thermal procedures seem most promising in this circumstance.
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Tags: brisbane, ndt, non-destructive testingApril 14th, 2010UncategorizedRead More >No Comments
Many small businesses spend far too much time on debt collection rather than their core business. Over the last 2-3 months I’ve noticed an increasing lag in payment cycles.
If you are in any sort of operation that uses small businesses as service providers or product suppliers it’s well worth your while to pay your bills on time and completely ignore to some “clever” accountants mantra of not paying until the second reminder. Guess what? People are human and they will pay back and pay forward. One way or the other you will pay in the end for screwing around your suppliers.
Here’s why:
1. If you pay on time you will get much better service. I know with my clients, the one’s who pay on time or early get the best service, day or night 365 days per year. These are A-Class clients. They pay on time or early, don’t bitch about the price, and as a result get excellent service and great value for money. They respect me, and I respect them. We both win.
2. If you don’t pay on time you reputation is on the line. Small business owners love to gossip. They slag off any customers who pay late. And with the Internet so freely available, your reputation can become crap overnight with one blog post. This leads into …
3. If you don’t pay on time, you can end up paying a premium. The current cost of money is about 1.5% per month. If your payment reputation is shite, than expect to pay at least 10-15 % more than if it were good or unknown. In some cases bad payers can be locked out of they supply chain completely and have to spend enormous amounts of time to find a new supplier.
With existing suppliers, if you screw them around, they will either add 10% to their next quote, or refer you to a lower-class competitor - hoping to send them broke because you don’t pay when due.
4. If you pay on time your staff don’t get harassed by debt collectors from your supplier’s accounts departments. This is a big source of staff burn-out. If you pay on time your staff won’t have to make up excuses for late payment and may actually start to enjoy their jobs.
In summary, if you want good service, good products, happier staff and ongoing loyalty, pay on time or before time and ignore your accountant’s advice.
What do you think? Why do you like early payment or not?
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Article supplied by Brisbane web designer and SEO Training.
Tags: accountants, Australia, brisbane, collection, debt, payment cycles, queensland, small business, suppliersDecember 22nd, 2008UncategorizedRead More >No Comments
December 16th, 2008infomercialRead More >No Comments