Re: defect detectors?

[Bruce Greening <norrail@optusnet.com.au>]

A wheel impact detector is a section of rail equipped with strain gauges that
measurers the additional strain in the rail caused by flats or scale on wheels.

There are also acoustic detectors that measure the sound of a wheel bearing
that is about to fail.

Another track side device that may fit into the category is a real time
measurement of wheel shape. Not installed in Aust. at this stage, but under
serious consideration.

Mark Bau wrote:

> in article 9c3pug$btkme$1@ID-65853.news.dfncis.de, Paul Jones at
> dj_wiseguy2_nospam@yahoo.com wrote on 4/24/01 6:02 AM:
>
> > "Bruce Greening" <norrail@optusnet.com.au> wrote in message
> > 3AE54E49.96503DAC@optusnet.com.au">news:3AE54E49.96503DAC@optusnet.com.au...
> >>
> >>
> >> Mark wrote:
> >>
> >>> Group, are there defect detectors in australia, or just usa?
> >>> and if not, why is this just a usa system of safety.
> >>> thanks
> >>
> >> There are certainly Hot box detectors, wheel impact detectors, draging
> >> equipment detectors in use on several Aust. systems.
> >>
> >
> > What do these look like, and what do they do??
> >
> > --
> > pk
> >
> >
> In the U.S. and presumably Australia the most common is a Hot Box detector.
> Small devices are mounted on the outside of the rail and measure the temp.
> of the axle box. They can also count axles.
> Dragging equipment detectors consist of a bar at sleeper height that has
> paddles attached to it, if a piece of dragging equipment hits a paddle the
> bar moves which breaks an electrical contact. Early DED's consisted of a
> soft wire basically attached to the sleeper, if the wire was broken by
> dragging equipment a relay dropped.
> I've not worked with wheel impact detectors.
> Another detector is a high/wide or loading gauge protector, these are often
> used on tracks with a lot of intermodal traffic. They consist of a wire
> strung over the track, if anything on the train is out of gauge the wire is
> broken and a relay drops.
>
> Mark

--
Bruce L. Greening

Norrail@optusnet.com.au
http://members.optusnet.com.au/~norrail