TECHNICAL DESCRIPTION Rail grinding unit for grinding traction

Document Sample
TECHNICAL DESCRIPTION Rail grinding unit for grinding traction Powered By Docstoc
					                                     TECHNICAL DESCRIPTION

                        Rail grinding unit for grinding traction heads
                                and re-profiling of Vignole rails

                                           Type AT 3103 2W

               (Designed for installation in rail-mounted carrier vehicle)

1.   General

1.1. Scope of application

For derusting new rails, removal of short pitch corrugation and striations as well as re-profiling of the rail
traction head and the running edge. Both rails can be machined simultaneously.

2.   Grinding principle

The rail grinding unit AT 3103 is designed on the one hand for grinding short pitch corrugation and
striations and on the other for deburring and re-profiling of the running edge and the outside edge of
Vignole and grooved rails. This machine can also be used for derusting new rails or smooth grinding of rail

2.1 Short pitch corrugation grinding

Short pitch corrugation consists of small ridges, which form on the traction head of the rail, causing noise
and wear in the rolling stock. For short pitch corrugation grinding the traction head is ground with four
rotating cyl. grinding wheels arranged in twin packs. The two wheels of a twin pack are in line. The angle of
the packs itselfs can adjust individually (Fig.A). It is possible to work with two different grinding angles each
pass. One or two grinding passes are made per operation, depending on the corrugation depth. By
adjusting the vertical axes of the grinding wheels the traction head can be re-profiled in a multiple pass
grinding mode (Fig. C). The difference in the grinding angles and the number of single pass operations
depends on the rail shape or on customer requirements (usually 4-6 pass operations). The resulting
grinding dust is suctioned off with a powerful vacuum cleaner equipped with a spark preseparator. The
sparks themselves are not suctioned off but are prevented from lateral discharge by baffle plates.
Autech AG CH-5102 Rupperswil                    Technical Description AT 3103 2W                     Page 2

                                                     Fig. A

2.2. Deburring/Re-profiling of running edge

After a long operating period of the rail the radius of the running edge may change or seamy formations
may occur. The following method is employed for deburring and re-profiling the rail edge: the edges are
ground with rotating grinding wheels and the wheel spindles can be inclined steplessly up to 72°. For
deburring purposes a fixed angle setting is adequate. For re-profiling several passes with an angle
difference of approx. 15° are necessary, depending on the accuracy of the radius required (Fig. D).

3.   Technical data and explanations

•    Gross weight of grinding unit: approx. 2’500 kg

•    Contact pressure when grinding: approx. 5,000 N (2,500 N/rail)
     This pressure acts as an “up lift” on the carrier vehicle! (no additional weights required)

•    Min. Curves radius of approx. 20 m can be worked. (It depends on the axle distance of carrier vehicle)
Autech AG CH-5102 Rupperswil                    Technical Description AT 3103 2W                       Page 3

•    The daily preparation time for the grinding unit is approx. 15 – 30 min. (emptying vacuum cleaner,
     replacing grinding wheels, general cleaning work).
     During the grinding period the 8 grinding wheels must be replaced approx. once an hour.
     Replacement time: approx. 5 min.

•    The travelling speed during grinding is approx. 2 – 4 km/h. Two different grinding angles are
     performed per pass. The width of each pass for traction head grinding is approx. 5 – 10 mm, and for
     running edge grinding approx. 2 – 5 mm. The pass width or grinding depth is set by the operator.
     During operation, the machine controls the seted value automatically (grinding wheel in-feed).

•    The grinding depth on the traction head is approx. 0.2 mm per operation. Approx. 1 mm per operation
     can be removed from the running edge (narrower pass).

•    For corrugation >0.2 mm it may be necessary to perform several passes with the same
     angle setting.

•    The average grinding rate for the complete traction head grinding operation of a UIC 60 rail with
     approx. 0.2 mm corrugation depth is approx. 150 meters track per h.

•    Grinding is normally done dry. For grinding in rain special grinding wheels are required.

•    Rail switches can also be ground partly, provided the necessary care is taken.

4. Dust vacuuming

The Scope of Supply includes a hydraulic driven dust vacuuming system, with an air capacity of 3’350
m3/h. The dust filter system “Dalamatic” has 12 filter bags, surface 1 m2 each.

The dust-loaden air enters the system through the intake nozzles and is returned by means of baffle plates.
The spark and the roughly dust are already separated. The fine dust is led thereafter by the really bag filter
system. The unique operation of the bag helps achieve high filtration efficiencies. First, dust accumulates
on the outer surface of the bag as air penetrates the fabric. Next, the blow pipe (jet tube) injects a burst of
compressed air into the filter bag. Airflow is the briefly reversed, inflating the bag and disloading dust. The
dislodged dust drops into the drawer beneath the filter. The Grinding unit itself is equipped with vertically
adjustable spark and dust shields.

5. Operation

•    Only two operators are required for grinding. For safety reasons, however, we recommend a third man
     as a driver and safety supervisor.

•    The grinding unit is operated by one man per rail. He is positioned outside the vehicle (to the side or
     behind it). During the grinding operation he adjusts the grinding pressure of feeds the grinding wheels
     per remote control. The machine holds the pressure on the adjusted level automatically! In addition he
     supervises or adjusts the grinding angle.

•    The vehicle can be stopped immediately by every operator by means of an emergency stop button

•    An approx. ten-day training period on site is adequate for training the operating personnel. For the
     technical maintenance of the machine and for carrying out minor repairs a training period of approx. 5
     days in a workshop is recommended.
Autech AG CH-5102 Rupperswil                                              Technical Description AT 3103 2W                      Page 4

6. Grinding efficiency, rate, grinding wheel consumption

Short-pitch corrugation grinding                                       Progress/h                    Grinding wheel
(only the rail head)                                                   in meters of track            consumption/h

Corrugation depth up to 0.2 mm                                         150 m                         approx. 8 wheels

Corrugation depth up to 0.3 mm                                         90 m                          approx. 12 wheels

Reprofiling                                                            Grinding progress/h           Grinding wheel
(only the running edge)                                                in meters of track            consumption/h

Reprofiling the running edge                                           150 m                         approx. 12 wheels

The unit price of a grinding wheel (100 x 110 x M20 left) is currently approx. CHF 24.00.

7. Technical requirements

The driving vehicle must have the following technical requirements for powering our grinding unit:
                                                                       Power:                     160 kW (grinding unit only)
                                                                       Oil pressure:              250 bar
                                                                       Oil flow:                  240 l/min.
                                                                       Oil cooler:                100 kW
                                                                       Oil tank:                  min. 300 l
                                                                       Working speed:             0- 5 km/h, stepless regulated
                                                                       Electrical power supply:   24 V / DC, 1 kW
Approx. Area needed for the grinding
unit:                                                                  Width                      approx. 2300 mm
                                                                       Length                     approx. 2200 mm
                                                                       Height                     1020 mm (below lowest carrier to railhead)
                                                                                                  approx. 2250mm incl. lifting unit

Approx. Area needed for the dust
vacuuming system
                                                                       Width:                     approx. 2’000 mm
                                                                       Length:                    approx. 1’000 mm
                                                                       Height:                    approx. 1’800 mm

For checking the possibility it is necessary to send us detail specifications and drawings from the basic
carrier vehicle.

Autech AG reserves the right to alter specifications without notice.

Edition: November 10