I was on my way to Mumbai by 51118 - 11058 slip coaches. our 51118 passenger arrived Chalisgaon Jn. right time. Indian rail information system was showing the connection, 11058 ASR-CSTM express late by about 4 hours. Then started mysterious shunting. I thought over it again and again and got more and more confused.
Presenting it for you all. There are two cases.
A) When both the trains are right time. 51118 arrives at Chalisgaon at 20.35 and 11058 arrives here at 20.50 and departs at 21.00 hours.
B) When 11058 is late for more than an hour.
A-1) 51118 arrives at Chalisgaon Jn. Generally loco link is Pune WDM 2. The composition of the rake is Loco-SLR-GS-S-12-S-11-B-4( Mumbai slip coaches) GS-GS-GS-GS-SLR. (CSN-DHI passenger coaches.)
A-2) The Mumbai bound slip coaches are detached just after 12139 CSTM-Nagpur Sewagram express clears PF 2 and are waiting for 11058 to arrive at PF 1.
A-3) 11058 arrives and loco (GZB WAP 4 or WAP 7) detached. Slip coaches are getting attached by the diesel loco that brought it from Dhule.
A-4) Shunting loco gets detached and regular loco link gets attached with the full formation of 11058.
A-5) Meanwhile 11058 departs for CSTM. Shunting loco goes at the end of PF 2 and then to PF 3 to get itself attached with the GS coaches of 51118 passenger.
A-6) The diesel loco pushes GS coaches of the passenger backwards towards the coaching depot for overnight maintenance. These will be taken out for its journey next day at 06.00 hours for 51111 passenger to Dhule.
B-1) Now the situation I have experienced when my connecting train, 11058 , was more than 1 hour late. PF 1 can not be kept occupied with slip coaches for so long as there is a rush of trains one after the another. 12810 Mumbai Mail, followed by 18030 Kurla Express and many more, the shunting takes place in a typical fashion.
B-2) After the departure of 12139 Sewagram express to Nagpur, the slip coaches are brought backwards through PF 2 as shown below.
B-3) Shunting continues. It is quite confusing to judge whats happening outside by sitting inside the coach.
B-4) Loco goes into middle during this shunting.
B-5) The GS coaches of Chalisgaon - Dhule passenger are being shunted back to Chalisgaon maintenance yard for overnight maintenance.
B-6) The loco and the slip coaches come back to PF 3 and the wait for 11058 continues silently, without disturbing other operations at the station.
B-7) 11058 arrives. GZB loco gets detached for the time being and slip coaches are shunted to 11058.
B-8) Slip coaches shunted. Diesel loco will get detached, Electric loco gets attached and train departs with its full formation for CSTM.
Happy that mystery is solved.