Grinding trolley
A grinding car (also known as a rail grinding car ) is a rail vehicle used on railways and trams that eliminates surface defects on rail heads.
A distinction is made between grinding trolleys with ( grinding railcar , grinding train ) and without their own drive ( grinding trolley , in the case of trams also grinding trolleys ). In the case of trams they belong to the work car , in the case of railways they belong to the auxiliary vehicles .
High tensile loads, high speeds on passenger and freight trains as well as large axle loads result in heavy loads on the superstructure . These stresses lead to high material wear, which affects the longitudinal and transverse profile of the rails through faults in the running surface. These runway defects are reasons for the fatigue of the steel, reduced tension on the fastening elements, greater stress on the sleeper support surfaces , destruction of the ballast structure , impairment of driving comfort, wear and tear on the rolling stock and high noise levels. It is therefore necessary to grind the rail heads at regular intervals.
Surface defects
Short waves
Crumbling
In order to determine damage to the rail surface, a rail surface measurement is necessary, which records the following errors:
Corrugations
Corrugations are regular, periodic bumps on the rail running surface with lengths of 3 cm to 8 cm and a depth of up to 0.4 mm.
Short waves
Short waves (e.g. slip waves ) are regular, periodic bumps on the rail running surface with lengths of 8 cm to 30 cm. The depths of the wave troughs can be up to 2 mm.
Long waves
Long waves are irregular bumps on the rail running surface with lengths of 30 cm to 250 cm. The depths of the wave troughs can be up to 1.5 mm.
other errors
Other defects include burrs, slingshot spots, breakouts, flaking, crumbling and faulty welds.
Types of grinding
.jpg)
New rail grinding
New rail grinding takes place on new lines before commissioning, otherwise as soon as possible afterwards, and is used to remove weld joints, the rolling skin , the edge decarburized layer, surface damage caused by production and the improvement of the cross-section.
Cyclic grinding
Cyclical grinding prevents the development of signs of fatigue on the driving surface and prevents undesired surface defects from occurring in the first place.
Reprofiling
Restoring the original profile shape to maintain a desired running and wear quality. This also includes the production of special profiles for the extension of the track (track gauge grinding) or the production of so-called "asymmetrical profiles" in the curve to support the curve running properties of the vehicles and to reduce the high forces on the rail.
Acoustic grinding
Grinding with particularly strict requirements regarding the roughness of the surface. This is done either with oscillating cup wheels or with sliding stones.
High speed grinding
Tram grinding car
Many tram grinding cars were created in the workshops of the transport company by converting retired vehicles , but there are also companies that build special grinding cars . A well-known manufacturer in the 1920s and 1930s was the company Schörling Waggonbau from Hanover, today the company Windhoff should be mentioned above all . Electric locomotives with a central driver's cab were a popular design ; the water tanks could be accommodated in the front end. An example of this are the four grinding cars built in 1960 for the Bucharest tram in the Romanian capital.
In normal rail operations, the rails are particularly contaminated by the fall of leaves in autumn, but also all year round by external influences such as brake sand and grit. In the case of trams, this is a frequent and operationally relevant problem, since the contamination affects braking behavior on the one hand and the flow of current through the rails used as a return line on the other . For this reason, grinding carriages are sometimes used to remove these unevenness and dirt.
These are equipped with lifting and lowering sanding blocks that are pulled over the rails to sand down the unevenness.
literature
- Lothar Marx, Detlef Bugenhagen, Dietmar Moßmann: Working procedures for the maintenance of the superstructure. Eisenbahn-Fachverlag, Heidelberg et al. 2001, ISBN 3-9801093-7-2 .
- Lothar Marx: Track machines for railway infrastructure. Eurailpress, Hamburg 2008, ISBN 978-3-7771-0371-6 .
Web links
Individual evidence
- ↑ Description of the grinding locomotive 610 at www.tram-info.de ( Memento of the original from November 29, 2014 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice.
