Ashok Leyland’s Legacy Plant Embraces Technology

Shopfloor August 2019 Ashok Leyland Ennore Plant Embraces Technology

For 70 years since it started operations, Ashok Leyland has remained one of the country’s leading players in the commercial vehicle (CV) industry, especially in the truck space, and boasts of a long-standing manufacturing history.

Auto Tech Review visited the company’s mother plant in Ennore, Chennai, where operations began way back in 1948. Auto Tech Review met up with KV Natarajan, Plant Head – Ennore, Ashok Leyland Ltd, to understand the various developments that have taken place at the company’s oldest plant as well as the trends in the commercial vehicle segment in India. Natarajan also provided information on the highly-customisable product portfolio, continuous modernisation of the facility, increased utilisation of automation technologies, sustainable methods of manufacturing and the preparedness for BS VI emission norms.


Ashok Leyland’s Ennore plant, which is tucked away on the northern outskirts of Chennai, is the oldest of its facilities (established in 1948 in collaboration with Austin Motor Company, England) for assembly of Austin cars. It was in 1950 that the erstwhile Ashok Motors and Leyland Motors, UK, agreed to take the collaboration route to import, assemble and manufacture Leyland trucks for seven years. However, the company received government approval in 1954 for manufacturing commercial vehicles, subsequently leading to the company being renamed Ashok Leyland the following year.

The Ennore plant is not just the oldest for Ashok Leyland, but is also said to be one of the most modern one, with over 66 % of the machines under six years old. The fully-integrated plant manufactures chassis as well as important aggregates like transmission, engine and axles for international assembly facilities. The plant also houses automated test beds, tool monitoring through radio-frequency identification (RFID) and material handling systems. The facility has a total headcount of around 1,800 associates along with numerous robots for automation.

The country’s second-largest CV player manufactures a complete range of products at its Ennore facility including buses & trucks under the Intermediate Commercial Vehicles (ICV) category, as well as engines for marine and industrial purposes. Ashok Leyland produces vehicle models that range from 9-49 tonne of gross vehicle weight (GVW). At the Ennore facility, buses are divided into ICV and Medium Duty Vehicles (MDV) models ranging from 7-12 m in length. A total of 177 models are manufactured as complete vehicles.

In trucks, the product range covers intermediate, medium-duty and heavy-duty variants leading to a total of 149 models in all. Additionally, customers have the choice of taking trucks as complete units with cabin and body or also just as an assembled chassis so that the body can be built externally. While trucks in the past were mostly bought by customers as chassis alone, Natarajan said there is an increasing customer trend towards buying fully-built trucks.

The Ennore plant leverages sustainable energy, with about 60 % coming from green power sources such as wind and solar. The plant is fitted with solar panels on the roof, which generate up to 2 MW of power that is consumed in the shopfloor, noted Natarajan. With regards to water conservation, the company practices the 4R principle of reduce, re-use, recycle and recharge. The plant also has abundant greenery, with over 30,000 trees spread across the facility.

The plant ensures a high level of traceability of components, with in-process checks to ensure quality


Ashok Leyland had been using individual manual machines for manufacturing products over the past, which included separate machines for lathe, milling, drilling, welding, etc. However, these individual manual machines have been replaced with CNC machines, following which the company added robots and mistake-proofing systems for safety critical processes, informed Natarajan. These steps have been undertaken for all the assembly areas of engine, chassis and axles.

The company also takes pride in introducing a number of technologies related to error-proofing and automation in order to bring the plant up to speed, in terms of modernisation. An example of the use of automation is that of the axle beam machining process. Sensors automatically measure and average the components, and subsequently carry out the machining process on the axle beams in the most optimal way possible. In addition, some lines feature gantries, which move components from one machine to another. Further, each machine has in-process gauging that will only allow components that meet the required quality criteria to pass to the next station, explained Natarajan. Machines performing certain critical functions have the capabilities to dynamically share process capability reports remotely to production engineers and shopfloor managers.


Ashok Leyland manufactures two-, three-, four- and six-cylinder engines at its Ennore plant, with the power rating ranging from 20-360 hp. While the lower-powered two- and three-cylinder engines are for industrial applications, the four- and six-cylinder engines are for manufacturing commercial vehicles. There are two types of engines manufactured at the plant – H series and N series – with the latter being a relatively new development.

The two engines are built on separate lines, which are individually flexible to assemble four- as well as six-cylinder formats respectively. Both the H and N series engines have the block, cylinder head and camshaft that are manufactured in-house by Ashok Leyland, with only the other components being sourced through suppliers. The short block of the engine is assembled on a single line, with the engine being moved with the assistance of automated gantries to the next line, which then carries out the assembling of the long block. Once the engines are assembled, each one of them is put through hot testing processes.

The assembly lines are ergonomic for operators to carry out critical assembly processes, while automation takes care of certain steps earlier carried out by manual machines


The chassis assembly consists of the assembly of the axles, which is an important step. The machining of the axle beams precedes their assembly onto the chassis. This machining is undertaken by highly-automated CNC machines, where each machine has replaced the work that was earlier carried out by eight manual machines. This upgradation has not only improved efficiency of the machining process, but has also cleaned up the shopfloor extensively, and also improved the quality standards.

The last processes for finished vehicles inside the Ashok Leyland Ennore plant take place in the final vehicle assembly hall. The main stations at the final assembly are frame loading, front and rear axle coupling, propeller shaft and silencer mounting, frame turnover, and fuel tank fitment, fuel hoses and battery. This is followed by the mounting of the engine and radiator, oil-filling as well as mounting of cab and ABC setting. Subsequently, the vehicle’s electrical connections and bumper fitment take place, after which the wheels are mounted and headlamps fitted. The final stations of the vehicle assembly are for wheel torque tightening, mechanical maximum speed cut setting, vehicle starting and air leak and oil leak checking. The vehicle assembly process culminates with the mounting of the mud guard, after which the vehicle is sent off to the testing track.


Ashok Leyland’s R&D activities are carried out at a separate location about 11 km from the Ennore facility. The designs for components and products are provided directly for production to the plant from this R&D facility. Natarajan said Ashok Leyland is moving towards a modular business programme, wherein higher customisation levels can be carried out on a single platform. Customers will be able to explore numerous options of using components and their state of tune, which could include steering box, engine power rating and transmission ratios, he pointed out. The price of the product will then depend on the level of customisation and the type of components selected by the customer. The modular business programme will be implemented from early 2020, when the company begins offering BS VI variants to its customers, Natarajan said.

This modular business programme results in the requirement for a high level of tailored components, for which the suppliers play a significant role. Once a customised order is received by Ashok Leyland, the order is forwarded to a plant in the vicinity of the customer. The company will subsequently forward the order of requirements to its suppliers, who are expected to deliver the required components in four hours. In order to ensure quicker delivery of components to assist in Ashok Leyland’s modular business programme, the company is training its suppliers in efficient manufacturing as well as in continuous quality improvement, Natarajan observed.

Ashok Leyland is a top manufacturer in the commercial vehicle segment, which maintains high levels of quality during manufacturing


Ashok Leyland is prepared for all upcoming legislative regulations, with regards to axle loads, bus body code or BS VI. Natarajan claimed that the company was the first to implement the new axle load regulations in the market, and exuded confidence that it is also ready to implement the bus body code as and when it comes into effect. With respect to BS VI, Ashok Leyland has already manufactured BS VI-compliant engines, which are currently undergoing trials.

Natarajan noted that there are two main challenges in selling fully-built trucks. Firstly, there is no government mandate on the sale of only fully-built vehicles from manufacturers, and secondly, the cost of vehicles will increase for such completely-built-up units. The enforcement of regulations for fully-built vehicles as well as the willingness of customers to spend a little more for a completely built unit from the company will further increase their demand.

The automotive industry has witnessed a downward trend in the current year. Natarajan said the company expects sales to pick up in the second half of 2019-20. This will also be a result of the launch of BS VI-compliant vehicles in 2020, which cost higher due to the addition of a number of components to conform to the new regulations. In addition, good monsoons and boost in government incentives would also help the automotive sector to grow further.

TEXT & PHOTO: Naveen Arul