Day out in BRC
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On 9th Feb 2018, got the chance to visit C & W Repair Workshop, Pratapnagar NG Diesel Loco Shed, Railway Museum and last but not the least BRC ELS as part of 13th IRFCA Convention.
The field trips for the day was divided into two parts, where C & W Repair Workshop, Pratapnagar NG Diesel Loco Shed and Railway...
more... Museum, which are located at Pratapnagar were supposed to be covered in pre lunch session and the all important ELS visit was planned for a post lunch visit.
First we visited C & W workshop, where we had a quick glance through various sections. Lot of wagons, mostly being BCNA and BTPN were getting repaired. Later we headed towards NG DLS, where 531 was basking under the shade of a tree, while 520 and 521 were waiting for their turn for maintenance. After playing with honk of these locos we headed towards the museum. The portraits and collections of Gaekwad Baroda State Railways took us into the glorious past and had a look at TimeTables of some of the trains that plied between Ahmedabad and Mumbai during British era.
After having a quick look at Turn Table(Narrow Gauge) situated opposite to the museum, we headed back to NAIR for lunch and left for much awaited ELS visit.
On entering ELS we were divided into groups and each group was assigned with a staff member. First we headed towards Pantos and Compressors section. Compressors as we all know serves the same purpose in locos as well. But to repeat, compressors have a low pressure unit and a high pressure unit. The low pressure side takes in the ambient air, compresses it and passes the same through an air cooler to make the air denser before feeding it to high pressure side, which further feeds the brake circuits and other ancillaries such as whistles, sanders etc.. There is a baby compressor also, which is used for panto operations. Due to frequent complaints by LPs and ALP regarding position of compressor in WAP4, compressor position in all the WAP4s which are coming for scheduled maintenance are changed.
In the panto section, along with old pantos, new pantos which are designed with lighter alloy were lying there. These pantos will gradually replace the older ones, as the locos undergo maintenance in due course. The panto's blade, which is the point of contact with the overhead equipment is made of carbon strips.
After covering the first section, we headed towards the pits where locos were rested. Here we spent substantial amount of time to understand the quill drive mechanism vs direct drive mechanism, which is one of the factors which differentiates WAP5 from other classes of locomotives in IR.
For that purpose, first we went under the bogie suspension of WAP5 30044. There we came to know that, TMs in WAP5 are full suspended and do not have any direct contact with axle gears. The drive happens through a flexible rubber based drive which transfers the output of the TM to a gear box which consists of 3 planetary gear arrangement which finally drive the wheel set. P5 has a bar(forgot the name), which helps in the axial movement of TMs during the bogie movement while the loco is in operation. The quill drive is now fully Indianized. As per the staff, it is not the drive mechanism, but the disc brakes for which shed wasn't happy, as compared to the brakes of other locos as it is costly to maintain and complicated to work on.
After having a look at WAP5, we went under the bogie suspension of WAP7 30480, which was standing on adjacent pit. In WAP7, the TM is mounted on a plate with 8 bolts and this plate is attached to the bogie frame. The TM pinion gear is attached to the axle gear which is the direct drive mechanism.
Regarding the query related to estimating the power generated by Regenerative braking, we got the answer that the energy is returned back to the overhead equipment and will be used by the locos itself.
We observed that the TMs, especially in WAP5, were suspended very low to the ground, on which we asked him regarding potential hits by foreign material like ballast, carcass etc. for which he replied that, the COW CATCHER is the lowest suspending part of the loco, which serves the purpose of minimizing these kind of hits.
As we all know, WAP7 transformers are of higher capacity as compared to WAP5 and WAP5s initially had HOG equipped when they arrived in India. However, they have been blanked out due to the load consideration of our trains. The HOG tapping of the initial WAP5s which were equipped has a rating of 550V which according to the shed wasn't sufficient.
He mentioned about E-W/N-S connections of HOGs which meant that there are 2 connections to the coaches. That is what we see 2 HOG connectors on the HOG equipped locos. One is N and the other is S or one is E and the other is W, you can call it in either way.
As per him, the shed is capable of handling all aspects of loco maintenance and renewals except for Periodic Overhauling, which is taken care by Bhusawal.
After an intensive session of gathering the technical stuff, we took a break by clicking pics with locos and inside the LP cabins.
While heading towards Transformers section, we could see lot of locomotives of various classes resting, getting maintained inside as well as outside the shed. Amidst them, we saw 30087 and 30090 basking under the sun together. Later we came to know that, these two locos would undergo trials of DPWCS in upcoming weeks.
In the transformers section, transformers, radiators and resistors of under maintenance locos were kept. Each transformer had a note pasted on them, comprising details like loco number, date of maintenance commencement, target date etc. Looking at the size of transformer, we can easily differentiate three phaser from the conventional tap changer :P
With limited time left for the visit, we rushed towards the Simulation room. First we had a look at the control room, where we had a look at the panel, which consists of controls to provide inputs to the simulator body. Later we went inside the simulator, to have a feel of ALPs who get trained there. After riding the WAG7 for 5 minutes, our session ended and we came out of the room.
With that, we were done with our field visit and headed back to NAIR to scratch our heads in Quiz Prelims.
Thanks to Shiva Kalyan sir, Prithvi Raj, Aproop and others, I was able to collect and write down this blog.
Pic 1: C & W Repair Workshop entrance
Pic 2: Axles lineup
Pic 3: In the workshop
Pic 4: 520 and 521 in NG DLS Pratapnagar
Pic 5: 531 resting under a tree
Pic 6: NG Turn Table at Pratapnagar
Pic 7: 30058 under maintenance
Pic 8: Pantographs section
Pic 9: 30090 resting along with partner(These twins were used for DPWCS trials in Feb)
Pic 10: Beneath the WAP5
Pic 11: Transformers section
