
These features ensure long working hours, even in the tough Himalyan geography
Sandvik's fully automatic, DT 922i and semi-automatic, DT 821C jumbo drills are enabling Max Infra to attain lower drilling costs per meter, with higher machine availability during the ongoing construction of the access tunnel in the Rishikesh-Karanprayag rail link project – one of the toughest geographies. P.P. Basistha witnesses first-hand the high-tech machines' efficient performance and high productivity, with ergonomic cabin designed to ensure complete operator comfort and safety during their long hours of work.
The Rishikesh-Karanprayag rail link in the Himalayas runs parallel to the River Ganges. The Chardham project comprises 12 stations, 17 tunnels with main and escape tunnels, ballast-less tracks, and 35 bridges. The project entails linking the newly constructed Rishikesh Railway Station with Gangotri, Yamunotri, Kedarnath, Badrinath, and with Chota Chardham.
Complexities in the project
The Chardham project is being constructed thru' tough Himalayan rocky terrain, the youngest chain of mountains in the world.
The site has certain geological complexities. The rock conditions are different, Geological conditions are different which is prone to earthquake, flash floods and other natural calamities.
The biggest challenge is to gauge the geological conditions and the hardness of rock in order to better asses the drilling and blasting pattern.
Safety of operator, people and equipment is of utmost importance due to harshest working conditions.

Sandvik's drillers and digital iSURE program helping in making quick progress
Giving shape to this highly critical infrastructure network are a combination of Sandvik's technologically advanced semi-automatic DT 821C and a fully automatic DT 922i jumbo drills, besides other machines.
The jumbo drills are penetrating the hard rocks with face drilling, bolt hole drilling, and long hole drilling with the required power for constructing the main and escape tunnels.
Construction of package-1 is being undertaken through New Australian Tunneling Methodology (NATM). The jumbo drills are working towards rapid execution of the project, combating the heterogeneous character of the rocks.
Informs Prasad, Senior Project-In-charge for the ADIT access tunnel, “The location where the access tunnel is being constructed has a new type of rock which is unlike the harder rock strata seen in other locations of the project. The new rock is a highly complex mix of sedimentary, gravel, and hard rock, despite which, Sandvik's highly automated machines are doing the drilling consistently and most efficiently.”
Prasad adds that Sandvik's fully automatic DT 922i, which is drilling the main tunnel face, works with very high accuracy as per the drilling plan and delivers better cycle times, leaving no scope for disruptions during the work. The core feature driving its superior performance is Sandvik's digital iSURE- ((Intelligent Sandvik Underground Rock Excavation software system), due to which, manual navigation and hole painting or marking on the face of the tunnel are no longer required. With iSURE, the operator can access all the data and controls on the touchscreen computer with easy to understand user interface.
Enabling smooth operator performance with a superior cabin design and features

He informs that the built-in Tunnel Rod Handling (TRH) system in Sandvik's DT 922i allows the operator to execute long holes drilling from the cabin itself. This adds to the safety requirement and saves the time spent in coupling and decoupling of the rods mechanically from the cabin.
Sandvik's unique drill plan software – iSURE® has been helping Max Infra tunnel engineers to analyze and make accurate navigation plans to optimize drilling and blasting. Says Prasad, “Since iSURE assists in geological interpretation of rock conditions and MWD feature (Measure-While-Drilling) capable of measuring 19 different drilling parameters in real time, immensely help the operators control the work cycle and process to ensure high accuracy and productivity in the highly complex terrain.
And that's not all, the Sandvik DT 922i also generates various critical reports on drilling operation, efficiency and utilisation of rig, drilling parameters, in order to assess the blasting vibration and pull-out analysis, prasad further added.
Started in 2019, the project has a completion schedule for 2025. Along with accuracy and consistency in performance, availability of the machines is also important for the project's timely progress.
Nishith Sharma, General Manager, Max Infra, says that iSURE with MWD is a super revolutionary software system in Sandvik Tunneling jumbos, which not only helps achieve uniformity in the drilling pattern but also ensures precision without significant overbreak and undercutting of the tunnel face, resulting in achievement of lowest possible cycle times.
Furthermore, the tech support rendered by Sandvik to all our operators through their Simulator Training Centre at Rishikesh, has immensely helped ensuring safe and efficient operations. The operators are first being trained and then given invaluable exposure before they actually go on site and operate the machines. “All these factors have helped us to make optimal use of these high-value machines,” he adds.
While iSURE have enabled Max Infra to derive higher productivity. better cycle times of DT 922i are backed by its efficient and user-friendly operating system and powerful engine. The power to support the functioning of the drilling tools comes from an external source which is activated by two powerful drifters (rock drills) mounted on each boom of the jumbo drills. There are two power packs on both sides of the machine, powered by individual hydraulic systems, and a booms basket at the center of the machine works as an access platform.
C. B. Gauda, Plant & Machinery In-Charge, Max Infra (for Package-1) concurs, “The DT 922i jumbo drill's accuracy has helped us make rapid progress towards meeting the project's completion timeline. Now we do not have to do any manual assessment or analysis on the required angle of drilling as the automation software on Sandvik jumbos does it all for us. Even the operators are motivated to operate this machine for longer hours, thereby increasing our utilisation.”
Overcoming challenges with automated features
The easy-to-understand digital displays enable the jumbo drills operators to drill at the required angle and precision, supported by the machines' automated functions; as shared by D.R. Joshi, Foreman, Max Infra (Package-1).
Joshi further stated that as the machine must work in the harshest of conditions continuously for hours, Sandvik has done a lot to ensure the safety and comfort for the operator. The DT 922i is equipped with sound-proof air-conditioned next generation iCAB operator cabin which helps the operators work for longer hours tirelessly adding to their efficiency with reduced cycle time.
Sandvik machines adapting to project needs, with focus on operator comfort and safety
Tunnel engineers Tarun and Sumit Rana of Max Infra say, “The automated face drilling and rock bolting through the machinery can be undertaken in 15-20 minutes as compared to 30-45 minutes achieved through manual arrangements. One of the key advantages of using these advanced machines is that we are able to share the data on the drilling performance to the project developer, management, and consultant, who can also review the utilization of the machines.”
What's also noteworthy here is the importance given to operator comfort and safety in the machines. Both the semi-automatic DT 821C and fully automatic DT 922i are working in synchronization and complimenting each other as per the tunnel conditions.
The best part about Sandvik is that, they understand the local implications and requirements of operations for their customers and are determined to respond to their needs quickly and effectively.
Mr. Gauda informs, “A very vital addition has been the safety guard on the machine's cab windscreen, which not only protects the operator from the falling big sized overcut rocks but also from stopping the probing rods from accidentally falling on the operator cabin.

Ensuring machine uptime with timely support and service
Projects of such magnitude and located in such complex strata need equipment that offer safety and automation for optimal utilization and high productivity for meeting the project's completion timelines. But the machines must be reliable enough to ensure high availability with minimum downtime.
Meeting this requirement are Sandvik jumbo drills with their cutting-edge technologies, ensuring faster and smoother drilling along with enhanced safety and help contractors overcome geological complexities. And to keep work from being interrupted and cause delays, Sandvik offers timely maintenance and 24x7 parts and rock tools supply to the contractors.

Aver Nishith Sharma and Prasad, “There is no doubt that the advanced and automated features of Sandvik's jumbo drills have reduced drilling costs per meter; plus, the technical support in terms of operations and maintenance training provided by the company has helped us in optimal utilization and uptime of the machines. The company provides the required parts and tools on time, thanks to a ready stock available at our main office on the site, and through Sandvik dealers.
Sandvik has a holistic approach to provide peace of mind to its customers
Mr. Ambareesh Munnangi, Chief Finance Officer, Max Infra commented, “Sandvik is one of the global leaders in mining and rock technology. They not only provide technically superior products but are also miles ahead in customer support. They offered us unique financing models through the Sandvik Financial Services corridor at optimum rates with seamless customer experience.”