# Mazagon Dock Shipbuilders

Mazagon Dock Shipbuilders Limited (MDL) (IAST: Majhagānv Dawk Shipbuilders Limiṭeḍ), formerly called Mazagon Dock Limited, is a company with shipyards situated in Mazagaon, Mumbai. It manufactures warships and submarines for the Indian Navy and offshore platforms and associated support vessels for offshore oil drilling. It also builds tankers, cargo bulk carriers, passenger ships and ferries.
MDL is a public sector undertaking managed by the Ministry of Defence, with the Government of India holding an 84.83% stake. Its shipbuilding segment has indigenously built stealth frigates, destroyers, guided-missile destroyers, corvettes, landing platform docks, missile boats, patrol boats, trailing suction hopper dredgers, cargo ships, cargo-passenger ships, platform supply vessels, Voith tugs and BOP vessels, while its submarine segment has built conventional submarines and stealth submarines. Both segments have also performed repair and refit activities.

## History

The company's shipyards were established in the 18th century. Ownership of the yards passed through entities including the Peninsular and Oriental Steam Navigation Company and the British-India Steam Navigation Company. Eventually, 'Mazagon Dock Limited' was registered as a public company in 1934.
The shipyard was nationalised in 1960 and is now a public sector undertaking (PSU) of the Government of India. In 2024, it became India's 18th PSU to receive the Navratna status from the Indian government.
Vice Admiral Narayan Prasad, AVSM, NM, IN (Retd), is the Chairman & Managing Director (CMD) of Mazagon Dock Shipbuilders Limited. The retired naval officer took over his current position on 30 December 2019.

## Activities

The company's activities are shipbuilding, submarine building, and fabrication of offshore structures. It has manufacturing facilities on both the Mumbai peninsula and on the mainland.
The yard has the capability to build warships, submarines, and merchant ships up to 30,000 deadweight tons (DWT). It can also fabricate wellhead platforms, process and production platforms, and jack-up rigs for oil exploration.

### Expansion

As of 2024, the shipyard has the capacity to handle 11 submarines and 10 warships at a time.
The shipyard has expansion plans worth ₹5,000 crore (US$580 million) to focus on security and executing export orders. Of this a major share of over ₹1,000 crore (US$120 million) is to be invested at its 40 acre-Nhava facility near Mumbai. This includes development of jetty and facility for holding the vessel, dredging and other associated works. MDL has awarded a contract worth ₹475 crore (US$55 million) to private-run Shoft Shipyard in Gujarat to erect a floating dry dock in the facility. Six blocks are to be built by Shoft which would be transported to Nhava for erection. As of now, 4 blocks has been completed. The dock will have dimensions 180 m (590 ft) by 44 m (144 ft) by 19.5 m (64 ft) in length, breadth and height, respectively and will be able to handle eight 12,800 tonne-class ships simultaneously. The dock will be used for construction and repair of larger commercial ships as well as for the Next Generation Destroyers.
Besife the existing facility, MDL will also develop a shipbuilding cum ship repair facility on 15 acres of land which is leased from Mumbai Port Authority. There are also plans to erect another graving dry dock of approximately 180 m (590 ft) by 60 m (200 ft) dimensions, and other ancillary facilities to double up shipbuilding and ship repairs capacity. Additionally, the new submarine orders could be executed in the existing facilities due to their inherent smaller dimensions.

## Naval projects
### Warships
#### Nilgiri-class frigate (1972)

The first warship built by MDL was the 2900-ton displacement INS Nilgiri, the lead ship of her class. She was launched on 15 October 1966 and commissioned on 23 June 1972. Five more frigates of this class were built over the next nine years for the Indian Navy.

#### Godavari-class frigate

While construction of the Nilgiri class was being completed, the Indian Navy proposed requirements for an indigenously designed and built frigate. This new frigate was to be of wholly Indian design and manufacture. To address these requirements, MDL designed and built the Godavari-class guided-missile frigates with a 3,800-tonne displacement and the ability to embark two helicopters. MDL built three ships of the class – the lead ship, INS Godavari, INS Ganga and INS Gomati.

#### Khukri-class corvettes

MDL designed and built the first two vessels of the Khukri-class corvettes for the Indian Navy. The lead vessel of the class was commissioned on 23 August 1989, and the second, INS Kuthar, on 7 June 1990. The remainder of the class was built at Garden Reach Shipbuilders and Engineers (GRSE) following a transfer of technology from MDL to diversify warship building capabilities to other yards, as well as to make room at MDL for larger projects.

#### Delhi-class destroyers

The next class of vessels designed and built by MDL was Project 15 Delhi-class guided-missile destroyers. These were powered by gas turbines and displaced 6,200 tonnes. The first of the class, INS Delhi, was launched in February 1991 and commissioned on 15 November 1997. The second, INS Mysore, was commissioned on 2 June 1999, followed by the last ship in the series, INS Mumbai, on 22 January 2001.

#### Shivalik-class frigates

The 6000-ton Shivalik-class (Project 17) frigates are the first warships with stealth features to be designed and built in India. These multi-role, guided-missile frigates have reduced radar signature and have entered service from 2010 onwards. At least three of this class have been constructed at MDL. The lead vessel of the class was commissioned on 29 April 2010. The last ship of the class, INS Sahyadri, was launched on 27 May 2005 and commissioned on 21 July 2012.

#### Kolkata-class destroyers

Kolkata-class vessels are the next-generation of guided-missile destroyers in the 7,400-tonne range to be designed and built at MDL. They incorporate stealth features. The lead vessel of the class was launched on 30 March 2006. At least three vessels of the class were planned. All three are in active service.

#### Visakhapatnam-class destroyers

Visakhapatnam-class vessels are the next-generation of guided-missile destroyers in the 7,500-tonne range to be designed and built at MDL. They incorporate stealth features and improved weapons and avionics compared to the Kolkata class. The lead vessel of the class was launched in 2018. At least four vessels of the class are planned.

#### Nilgiri-class frigates

Nilgiri class vessels are the next-generation of guided-missile frigates in the 6,500-tonne range to be designed and built at MDL and GRSE. They incorporate stealth features. The lead vessel of the class was launched on 28 September 2019. Seven vessels of the class were built by MDL and GRSE. INS Mahendragiri, the seventh and final ship of the class was launched in Mumbai on 1 September 2023.

#### Coast Guard vessels

The yard builds offshore patrol vessels (OPVs) for the Indian Coast Guard. These vessels are specialised ships built for patrolling, policing, and search and rescue operations in India's exclusive economic zone. Each carries a helicopter on board. Seven such ships have been delivered.

#### Floating police stations

Based on the order from the Border Security Force (BSF), the yard started construction of floating border outposts (BOPs). Essentially these BOPs are floating police stations with four high-speed boats. The yard has delivered 9 out of an order of 14 BOPs.

#### Other vessels

Among other ships, the yard has built three fast missile boats, a cadet training ship, and other utility ships for the Indian Navy. It has also built Kangan class water tankers for the Iranian naval forces.

### Submarines
#### Shishumar-class submarine

The Shishumar-class submarines are a variant of the Type 209 diesel-electric submarine designed by Howaldtswerke-Deutsche Werft. Two vessels of this class were constructed at MDL, which are the first indigenously built submarines in India. INS Shalki was commissioned on 7 February 1992 and INS Shankul was commissioned on 28 May 1994.

#### Kalvari-class submarine

MDL has built six diesel-electric submarines of the Kalvari class under a technology-transfer agreement with Naval Group. INS Kalvari, the first in this class, was commissioned on 14 December 2017 from Naval Dockyard in Mumbai.

### US Navy

In September 2023, MDL became the second Indian shipyard after Kattupalli Shipyard of Larsen & Toubro to sign a Master Ship Repair Agreement (MSRA) with the US Government, represented by NAVSUP Fleet Logistics Center (FLC) Yokosuka, for United States Navy's Military Sealift Command Fleet Support Ships. The ships operated by MSC are non-commissioned US Navy “support vessels” with civilian crews bearing the prefix “USNS”. Under the agreement, the US Naval ships of the Central Command that are in voyage are to be repaired in India.

## Commercial projects
### Offshore platforms

MDL builds offshore oil drilling platforms. It operates facilities at Alcock, Mumbai, and Nhava Yard for the construction of platforms with wellhead, water injection and production separator and glycol process capabilities, as well as jackup rigs, SBMs and other offshore structures.
Repair and maintenance jobs on offshore rigs are undertaken at Alcock; jackets up to 80 metres (260 ft) length and 2,200-tonne weight can be constructed. At Nhava, jackets up to 80 metres (260 ft) length and 2,300-tonne weight, main decks up to 550-tonne weight and helipads of 160-tonne weight can be constructed.
The yard builds specialist vessels able to clean oil spills and fight fires on offshore drilling platforms.
A welding training school develops and maintains welding techniques and procedures.