Test Methods
IAV constantly develops new, tailor-made solutions to satisfy widely varying customer demands. Here are a few examples:
Checking the filling cycle|
A transparent rail has been created for analyzing the filling cycle.
This makes it possible to record the filling cycle with a camera and
identify air pockets in the rail. |
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Determining the effect of force on the injector
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The effect that force has on the injector was investigated by
integrating a force-measuring sensor into an injector clamp. In
particular, changes in the injection rates and injected quantities were
determined in relation to the level of force exerted. In addition,
optical spray investigations were carried out in the pressure chamber
to identify the effect force has on spray geometry. |
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Leakage measurements on diesel injection systems
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Leaks are caused by tolerances that occur during assembly, while the
engine is being installed or by material fatigue at joints and
connections. A test procedure designed by IAV permits their early
detection and provides the key to defining remedial action. The
procedure uses the following modules: |
Leakage detection by means of the flame ionization method (Fast FID)
| The potential leak is screened off and enveloped by a carrier gas that entrains any escaping hydrocarbons. The combustion of the hydrocarbons in an H2 flame produces ions with a concentration proportional to the escaping HC concentration. The measuring instrument has a low response threshold (from 1 ppm) and short detection times (approx. 3 ms). |
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Load measurement in a high-pressure connection
The quality of seal is determined by the contact pressure of the two
sealing surfaces in a high-pressure connection. This measurement
variable changes if assembly tolerances are exceeded and also as a
result of aging. Advantages of the solution devised at IAV:
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Determination of roughness at contours of high-pressure connection components
| Component roughness is determined in collaboration with highly specialized partners. Superimposing the results of both sides of a sealing surface produces valuable findings on local micro-fissures. The raw data can be taken as a basis for generating a roughness characteristic, shedding light on the cause of roughness. |
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Determination of roundness on contours of high-pressure connections
| Capable of being determined before and after assembly, component roundness at the sealing surfaces of a high-pressure connection provides important findings on permanent component deformation. These are also analyses carried out by IAV in collaboration with highly specialized partners. |
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Analysis of material deformation on the basis of micrographs
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Producing micrographs has the purpose of analyzing material properties.
The example here shows a pipe nipple and male pipe fitting analyzed in
collaboration with highly specialized partners. Detailed image 1 depicts the outer sealing surface of the pipe nipple. The compressive stress that occurs after tightening the screw connection has caused the material to yield, discernible from inhomogeneous grain contours and grain elongation in the direction of deformation. |
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