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37
TEXTS FOR HOME READING
T
EXT I
Read the text and translate it with a dictionary if necessary. Use the termino-
logical dictionary provided at the end of the present manual.
M
AINTAINING RAILWAY TRACK IN ICE AND SNOW
Practical railway experience shows that running a railway in harsh winter climate de-
mands a lot more than merely keeping tracks snow free. Snow can infiltrate unprotected
equipment on locomotives and coaches causing breakdowns. Ice can prevent doors from
opening or closing. Severe frost can damage the permanent way, leaving buckled tracks or
broken rails.
Railwaymen in different countries have been working on this problem and here is one
example which shows how it can be solved.
Danish State Railways (DSB) have developed a gas-fired point heater that is controlled
by a snow detector. DSB have already invested 6 million Danish krones installing the
equipment at Fredericia, an important junction on the network. The equipment is also in
use in Copenhagen.
The detector is placed near the track, about 1m above ground level. The detector and
point heater are linked to a control center.
The sensor is pre-set to react at a certain temperature - on DSB this is 2° С. Snow-
flakes, caught by the detector’s screen, melt on reaching the heater sensor. The process is
recorded electronically at the control center, and the point heater is switched on either
manually or automatically. DSB have found that gas consumption is reduced by up to 40
per cent with automatic operation.
The point heater consists of zigzag shaped pipes containing gas burners. They cover a
much larger area than existing point heaters.
Individual control boxes are provided near each pipe installation. Each box has a light
which is illuminated in case of failure. Faults are simultaneously recorded on the control
center panel. Gas containers are also monitored - a light indicates when the contents drop
below 30 per cent.
T
EXT II
Read the text and translate it with a dictionary if necessary. Use the termino-
logical dictionary provided at the end of the present manual.
P
OLYMER MATERIALS USED ON RAILWAY
In the last few years the development of new methods in the construction and mainte-
nance of railway tracks has accelerated. Among these, polymer materials always play an
important part. Polymer materials are widely used for repair of structural elements in the
permanent way and sub-structure, because they offer many technical and economic advan-
tages. By these materials we understand plastics (thermoplastics and prestressed plastics)
and elastomers (rubber and similar materials).
In general polymer materials offer as many technical advantages as no other kind of
material known. These advantages are: a) suitable strength and resistance to static and dy-
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