SBB Em 831

Em 831
	SBB Em 831 001 in Frauenfeld
Numbering:	SBB Em 831 000-831 002
Manufacturer:	RACO (Robert Aebi AG, Zurich)
Year of construction (s):	1992
Retirement:	2012-2013
Axis formula :	C.
Gauge :	1435 mm ( standard gauge )
Service mass:	54 t
Top speed:	80 km / h
Installed capacity:	900 kW
Power transmission:	hydraulic
Number of traction motors:	1

The Em 831 is a three-axle, diesel-hydraulic shunting locomotive of the Swiss Federal Railways (SBB).

history

In 1989, SBB ordered three prototypes of the Em 3/3 type from Robert Aebi AG (RACO). Originally 45 locomotives were to follow these three. Due to a delay in the braking equipment, the first locomotive was not able to take the test drive until December 1991. With the introduction and renewed revision of the UIC type designations at approximately the same time , these machines were put into service as Em 831 000 to Em 831 002. The official handover of the Em 831 000 took place in February 1992, the other two in June 1992. They were designed as a universal shunting vehicle that should also be usable for construction services. It was planned that in addition to high loads at low speeds, construction and freight trains could also be transferred at line speed. As a novelty at SBB, a radio remote control was built in from the start.

The Em 831 was the largest and also the last type of locomotive developed by RACO. After these three machines, 21 vehicles were delivered until 1995, after which rail vehicle production was discontinued.

The rather poor running conditions at higher speeds meant that a series order was not made and the four-axle Am 841 was procured instead .

Technology and commitment

The chassis frame consists of two continuous longitudinal beams with welded end plates and thus forms a torsion-resistant unit.

The machines have a Cummins diesel engine of type KTA 38-L. This engine can deliver a maximum output of 900 kW (1220 hp).

The initially existing Scharfenberg shunting coupling was removed after a short time. The built-in multiple control was not according to plan, the radio remote control was seldom used, and by the end of its deployment at SBB Cargo it had already been shut down.

SBB designation	TSI number	Installation	Manufacturer	Serial number	sale	Current owner
Em 831,000	98 85 5 837 827-5	2.1992	RACO	2003	2013	Stauffer
Em 831 003	?	6.1992	RACO	2004	2012	Stauffer
Em 831 002	?	6.1992	RACO	2005	2012	Stauffer

commitment

The vehicles were used in shunting services in Biel, Suhr and Winterthur, among others. Later they were mainly used in the Suhr-Lenzburg-Birrfeld area, with Suhr being the main location.

Initially they were assigned to the Olten depot, later they were maintained in the RBL service facility.

All three vehicles came to SBB Cargo when it was divisionalized in 1999.

With the commissioning of the Eem 923, the three vehicles left the SBB Cargo vehicle fleet as a splinter group and were all sold to the Stauffer company in Frauenfeld between 2012 and 2013.

Whereabouts

The upcoming revisions in 2011 and 2012 were postponed or not completed and the machines of this type of splinter were decommissioned in 2012 and 2013. They disappeared two years earlier than their 30 years older sisters in the Em 3/3 series . They were sold to Stauffer Eisenbahn- und Spezialfahrzeuge , which they rent and look after nationwide. The former Em 831 000 is already in use again for the Stauffer company as Em 837 827-5.