Rupak Chattopadhyay Profile picture
Jan 15, 2022 13 tweets 7 min read Read on X
Between 1925 and 1960 all electrified #railway tracks in #India operated on a Direct Current system. The last sections of 1.5 kV DC from Mumbai to Panvel and Thane to Vashi, were upgraded to 25 kV AC in April 2016. Here is a look at the now extinct DC locomotives of India.
WCP-1/2 ordered by GIPR to a Swiss Locomotive & Machine Works design for operations over the Western Ghats in 1928. 22 Vickers built locos entered service in 1930 and served into the mid-1980s. With a top speed of 137 km/h, the locos offered 15,295 kgf of tractive power.
WCP-3/4 were two locomotives ordered to General Electric Company and Brown, Boveri & Cie. designs for evaluation purposes in 1928. Built by R&W Hawthorn, Leslie & Co. both offered lower tractive effort and speed than the WCP-1 (EA-1). They operated into the late 1960s.
WCG-1 were ordered in 1926 by GIPR. These were meant for freight operations and also served as bankers. 41 of these locos were built to a Brown, Boveri & C design by by SLM in Winterthur and at Vulcan Foundry. Withdrawn in 1993. Top speed 80km/h and tractive effort 30,482 kgf.
The YCG-1/EM-1 was a class of 7 electric locomotives built by English Electric in the 1930s for use on the metre-gauge electrified lines in the Chennai area by the South Indian Railway Company . These freight locos were withdrawn in 1965.
WCM-1 were the first new class of mixed use locos built by Vulcan Foundry and English Electric. They entered service in 1955. A total of 7 WCM-1 locomotives were built and the last one was withdrawn in 2000. The loco was capable of 120km/h and a tractive effort of 31,000 kgf.
12 WCM-2 were first ordered for the Kolkata suburban section. They were transferred to Central Railways when Eastern Railway converted to 25 kV AC system in 1960. These were broadly similar in performance with the preceding WCM-1, but reputedly less reliable.
In 1958, three WCM-3 were ordered from Hitachi for 3 kV suburban services around Kolkata. While they operated until the early 1990s, the WCM-3 proved a failure in Indian service with low reliability and tractive power. They were transferred to CR in 1961.
WCM-4 was developed by Vulcan Foundry and English Electric and built for Indian Railways by Hitachi. A class of 7 were delivered to Central Railway in 1959 and served into the late 1990s. Offered marginally greater tractive effort over the WCM-1/2.
A total of 21 WCM-5 locomotives were built at Chittaranjan Loco Works between 1961 and 1963. These were a local developments of the WCM-1 and were used on many Express trains like the Deccan Queen, Indrayani Express etc as well as in Freight Duties until the 1999.
WCG-2 is a class of 57 DC locomotives developed in India and built at by CLW between 1970-78. This mixed use loco is known for doing passenger duties and banking duties in pushing up trains over the Bhor and Thull ghats. Last loco withdrawn in 2012. Tractive effort of 35,600 kgf.
WCM-2 was a class of two (the last DC) locomotives built by CLW as attrition replacements for Central Railways older DC locos in the mid-1990s. They combine the body of the WAM-4 class loco with the bogies of the WAG-7 class. Both converted to 25KV AC by ELW -Bhusuwal in 2008.

• • •

Missing some Tweet in this thread? You can try to force a refresh
 

Keep Current with Rupak Chattopadhyay

Rupak Chattopadhyay Profile picture

Stay in touch and get notified when new unrolls are available from this author!

Read all threads

This Thread may be Removed Anytime!

PDF

Twitter may remove this content at anytime! Save it as PDF for later use!

Try unrolling a thread yourself!

how to unroll video
  1. Follow @ThreadReaderApp to mention us!

  2. From a Twitter thread mention us with a keyword "unroll"
@threadreaderapp unroll

Practice here first or read more on our help page!

More from @RupakChatto

Jul 23
Now that it is going to be curtains on the @IAF_MCC MiG-21s after 60+ years of service, it is worth remembering that no other type served in the numbers and variants as the MiG-21. Over the years, no fewer than twenty four operational squadrons and four training establishments operated 840+ aircraft of the type.

The first MiG-21 type to join the IAF in 1963 were six MiG-21 F-13 Type 74, followed in 1965 by six MiG-21 PF Type 76.Image
In 1966, based on its experience from the war in 1965, ordered more MiG-21s. This time the much improved MiG-21 FL, Type -77 variant. 38 aircarft were delivered from the USSR and another 197 were manufactured by @HAL_india between 1966-73. The MiG-21FL (Type 77) and MiG-21PF (Type 76) are visually distinguishable by several key features. The FL variant has a larger tail fin with a brake parachute housing at its base, while the PF's brake parachute is housed in a ventral fairing. The FL also features a detachable gun pod (GP-9) and a larger fuel capacity compared to the PF. The GP-9 was a specific requirement articulated by the IAF based on its 1971 experience. The Type-77 also offered multirole capability in being able to deliver 500kg bombs. The aircraft would be retrofitted after 1982 with additional underwing pylons.Image
Begining in 1973, the IAF began inducting an upgraded variant in the form of 34 MiG-21MF and 160 MiG-21M fighters. The former were directly supply from the USSR with the R-13 engine a built-in GSh-23L cannon freeing up the centre pylon for a droptank. The M used a modified R-11 engine which was already under manufacturing for the Type-77. Collectively known as the Type-96, the M/MF aircraft offered zero-speed, zero-altitude ejection seat , 4 wing pylons, newer avionics and more fuel. Visually it was distinguished from its predecessors by its thicker spine. The Type-96s would all be upgraded in 2001-04 with a the more modern R-13 engines.Image
Read 7 tweets
Jun 27
Thanks to Kapil Chandni and the @indiannavy for their document on the building of the carrier INS Vikrant. It has some interesting information on how the design evolved over almost a two decade period between 1980 and final sanction in 1999. Here is this story. 1/n Image
In 1980, the Directorate of Naval Design (DND) prepared a concept design of a ‘Helicopter Carrier’ based on the hull form of MV Harshavardhan, a merchant vessel . Image
This was followed by in 1985 a formulation of Outline Staff Requirements (OSRs) a Sea Control Ship (SCS) of 35,000 ton. Image
Read 8 tweets
Feb 7
Purnima Sinha (1927 – 2015) was a physicist and one of the first Bengali women to earn a doctorate in physics in the field of x-ray crystallography of clay minerals. She was born to Dr. Nares Chandra Sengupta, a constitutional lawyer and progressive writer. She married the anthropologist Surajit Chandra Sinha, later vice-chancellor, Visva-Bharati University.Image
After obtaining her MSc degree in Physics from Calcutta University, she joined for her PhD work in 1951 under the legendary physicist Satyendra Nath Bose. Purchase of equipment in the early years of independence was difficult and she built instruments with components available in the open market. She recalled “we had put together our X-ray equipment from the World War II surplus gathered in the lane behind Dr Bidhan Roy’s house”. Purnima’s PhD research was entitled “X-ray & Differential Thermal Analysis of Indian Clays”. She also worked with Nobel Laureate physicist Paul M Dirac when he was a visitor to Calcutta University in 1954.Image
In the early 1960s, Purnima worked on the origin of life with clay as the substrate in the Biophysics Group at Stanford University, California. She observed that the spacing in the clay structure, determined through X-ray studies, corresponded to the pitch of the DNA double helix. Since then, she remained interested in biophysics till the end of her life. After her return from the USA in 1964 she spent most of her professional life at the CGCRI, Kolkata till she took voluntary retirement in 1986.
Read 5 tweets
Jan 6
Pafulla Chandra Roy (1861 – 16 June 1944) was an Indian chemist, educationist, historian, industrialist and philanthropist. A product of the Bengali Renaissance, he was the founder of Bengal Chemicals & Pharmaceuticals, India's first pharmaceutical company. He is the author of A History of Hindu Chemistry from the Earliest Times to the Middle of the Sixteenth Century (1902).Image
The book draws uses primary sources to deal with a ranage of subjects inlcuding, metallury and rare-earths extraction. Topis include Colophon - The Rasas - Abhra - Vaikranta -copper Pyrites Vimala - Silajatu - Sasyaka - Extraction of Copper - Chapala Rasaka - Extraction of Zinc - The Uparasas or Inferior Rasas Sulphur Gairika Kasisa Tuvari Talaka Manassila - The Afijanas - The Common Rasas - Navasara and other Rasas - The Gems - Vajram - General Process of Reducing Gems to Ashes - On Metals - Gold - Silver - Copper - I on - Tin - Lead Brass - Bell Metal, &c. - Initiation into Discipleship - On the Laboratory - Tests for Killed Iron - AntimonyImage
Prafulla Babu was born in the village of Raruli-Katipara, then in Jessore District (now Dighalia, Khulna), and was the third child and son of Harish Chandra Raychowdhury. Ray's great-grandfather Maniklal had been a dewan under the British East India Company's district collector of Krishnanagar and Jessore. The ruins of the Ray Bari still exist.Image
Image
Image
Image
Read 12 tweets
Mar 28, 2023
Meet Nelson Wang, the inventor of Indian-Chinese the "Chicken Manchurian". Wang was born in Calcutta's Tangra China Town in 1950. When his family moved to Canada in the 1977, Nelson decided to move to Bombay.
#ChickenManchurian #Chinese #Cricket #Foodie
Strating out as a nightclub limbo dancer and fire-eater, he found a job was as a cook at Frederick's, a Chinese restaurant in Colaba and where the legendary Raj Singh Dungarpur, then President of the Cricket Club of India was a regular.
Frederick's was asked if could cater to Cricket Club of India, but turned down the offer. So Nelson took on the challenge. It was here that Dungarpur, who liked fried food asked Nelson for something spicy and crunchy with a gravy.
Read 6 tweets
Mar 27, 2023
INS Kamorta P177, later P77 was the first Peyta ASW ship commissioned into the Indian Navy on21 November 1968. In 1971 she served in the Eastern fleet as part of its ASW screen and intercepted blockade runners. She was decomissioned in 1991.
INS Kamorta P28 is the leadship of the Project-28 ASW corvettes built by @OfficialGRSE and commissioned in 2014. He is armed with OTO Melara SRGM, AK-630M CIWS, RBU-6000 and Torpedo tubes. She will be oufitted with a 50km VL SRSAM from DRDO.
Read 4 tweets

Did Thread Reader help you today?

Support us! We are indie developers!


This site is made by just two indie developers on a laptop doing marketing, support and development! Read more about the story.

Become a Premium Member ($3/month or $30/year) and get exclusive features!

Become Premium

Don't want to be a Premium member but still want to support us?

Make a small donation by buying us coffee ($5) or help with server cost ($10)

Donate via Paypal

Or Donate anonymously using crypto!

Ethereum

0xfe58350B80634f60Fa6Dc149a72b4DFbc17D341E copy

Bitcoin

3ATGMxNzCUFzxpMCHL5sWSt4DVtS8UqXpi copy

Thank you for your support!

Follow Us!

:(