Blade test

STANDARD REHEAT TREATED BLADES TESTED AT 310 MPa, McCall <6)... 

SERVICE EXPOSED BLADES, TESTED AT 310MPa, McCall (6)... 

J. D. Capps, G.J. Smith, D.B. Turley, W.D. Borella, H.M. O Brian, W.F. Roby, R.J. Anderson, T.T. Engine Testing of Thermographic Phosphors Part 1. Pratt and Whitney Fixed-Blade Test and Part 2. Virginia Polytechnic Institute Turbine-Blade Test, Technical Report No. ORNL/ATD-31 Martin Marietta Energy Systems, Inc., May 1990. 

The micro-blade test consisted of linearly increasing the applied load from 10-1000 mN, while slowly sliding the micro-blade at 1 mm/s, with continuous multi-sensor process monitoring. 

Rubbing between two solid surfaces is a common case that can occur in everyday use of liquid repellent materials. However, there are also occasions when surfaces could come into contact with sharper objects (e.g. knives, pens, forks, etc.) that induce much more severe damage. Driven by this problem, a few studies have been published where liquid repellent surfaces undergo blade tests, which are practically linear abrasion tests but instead of a flat abradant material the rubbing is performed by a sharp blade. 

The superomniphobic polyester fabrics tested with the blade test by the same group (Zhou et al.) were also tested under laimdry and circular abrasion [49]. In the machine laundry process, the coated fabric did not show changes in the APCAs of water, hexadecane or ethanol after 200 cycles of washing. However, the SA values increased to 4.5°, 36.7°, and 47.5° for water, hexadecane, and ethanol respectively. After 20000 abrasion cycles nearly no nanoparticles could be observed on the top surface. However, the damaged surface after the abrasion test was healable when the coated fabric was heated at 140° C for 30 min. The APCAs of water and hexadecane recovered to 171° and 152°, respectively. However, the heat treatment could increase the APCA of ethanol only to 127°. 

As noted earlier and readily seen by the complexity of variables, adhesion testing is a very inexact science. Many tests have been devised in order to characterize the adhesion property. These include both qualitative and quantitative test methods. Examples of qualitative tests are the Scotch tape test and razor blade tests which certify that the adhesion exceeds some... 

This test attempts to characterize the brittleness of bitumen at low temperatures. It consists of measuring the temperature at which fissures appear on a bitumen film spread on a blade as it is repeatedly flexed. This test is delicate and of questionable reliability, but it is currently the only one that allows the elastic behavior of bitumen on decreasing temperature to be characterized. It is standardized in France (T 66-026). 

This type of coil was prepared from copper cladded printed circuit board material by applying photolithographic techniques. The p.c. board material is available with difierent copper thicknesses and with either a stiff or a flexible carrier. The flexible material offers the opportunity to adapt the planar coil to a curved three dimensional test object. In our turbine blade application this is a major advantage. The thickness of the copper layer was chosen to be 17 pm The period of the coil was 100 pm The coils were patterned by wet etching, A major advantage of this approach is the parallel processing with narrow tolerances, resulting in many identical Eddy current probes. An example of such a probe is shown in fig. 10. 

Before testing, the blades have to be painted black to ensure a symmetrical thermal radiation. Painting is done in an additional cabin. After the measurement the blades or vanes are cleaned in an ultrasonic bath. 

The tested blade is flowed through either with hot or cold compressed air with a duration of max. 5 seconds The maximum heat temperature can be adjusted at 250 °C. 

For the examination of the applied metallic or ceramic layer, the test object is heated up from the outside The heat applying takes place impulse-like (4ms) by xenon-flash lamps, which are mounted on a rack The surface temperature arises to approx 150 °C Due to the high temperature gradient the warmth diffuses quickly into the material An incorrect layer, e g. due to a delamiation (layer removal) obstructs the heat transfer, so that a higher temperature can be detected with an infrared camera. A complete test of a blade lasts approximatly 5 minutes. This is also done automatically by the system. In illustration 9, a typical delamination is to be recognized. 

RCT are designed to successfully solve a whole number of tasks in nuclear power when testing fuel elements, in aviation and space industry when testing construction materials, nozzles and engine units, turbine blades and parts, in electromechanical industry-cables switching elements, electric motors in defense sphere- charges, equipment in prospecting for research of rock distribution and detection of precious stones in samples. 

In co-operation with LM Glasfiber, a complete section of a rotor blade was produced with a number of well defined defects in order to perform an initial sensitivity test by means of ultrasound, vibrations techniques and real-time radiography. Based on the results of this initial test it was found that automated ultrasonic inspection was the best suited teclmique. In co-... 

Today the coin-tap test is a widely used technique on wind turbine rotor blades for inspection of thin GFRP laminates for disbonded and delaminated areas. However, since the sensitivity of this technique depends not only on the operator but also on the thickness of the inspected component, the coin-tap testing technique is most sensitive to defects positioned near the surface of the laminate. Therefore, there has been an increasing demand for alternative non-destmctive testing techniques which is less operator dependent and also more sensitive to delaminations and disbonded areas situated beyond thicker GFRP-laminates. 

Slides Tungsten filaments, turbine blades, lead drain pipes and organ pipes, glaciers creep-testing rigs micrographs of creep cavities. 

The main plant s manufaeturing faeility was also responsible for produeing the new diffuser and first- and seeond-stage stator assemblies, in addition to many other miseellaneous parts. The owner/user s spare rotor was used as part of the rebuild. Complete disassembly, dimensional, and penetrant inspeetions of the rotor were eondueted. New blades were installed in the dises. Final qualifieations of the rotor ineluded rotor stud streteh tests, balaneing, and meehanieal and elee-trieal runout eheeks. 

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