
A tunnelling project is a race against time and costs. Getting it right from the very beginning requires knowledge, skill and experience, as well as a proper range of equipment that fulfils the customer’s tunnelling requirement. Sandvik has been giving drilling solutions for more than 50 years, by creating cutting-edge technology that meet the needs of modern-day tunnelling.
Sandvik 800 series DT821C is a twin boom electrohydraulic semi-automatic tunnelling Jumbo that offers the right solution for any tunnelling application like face drilling, bolt hole drilling, and mechanized long-hole drilling. It provides efficiency and accuracy along with reliable performance.
The fast and user-friendly Jumbo produces excavation results of the highest quality and with the lowest costs. Its hydraulic rigs-controlled systems with advanced automatic functions include MWD (Measure While Drilling) data collection and hole length control system as per the drill plan.
Advanced Intelligence
To produce the highest repeatability and the best possible excavation predictability, the DT821C is loaded with Sandvik T-CAD+ and iSURE® 8.0, a revolutionary tunnel management tool, which offers an efficient way of designing blasting and drilling pattern. The iSURE® ensures accurate drilling and optimized blasting according to plan that gives better pull-out, significant reduction in scaling costs, better mucking efficiency, and smoother collaring in the following round.
iSURE® uses the most critical spot, the blast plane, as the basis for the whole planning process. As the drill plan is implemented to fit the blasting plane, the hole bottom spacing and the burdens will be adjusted accordingly; the used charge defined and the cracking zone examined. As a result, hole locations and blasting are optimized. A range of practical features will allow the operator to fine-tune the process online, depending on the rock conditions.

Efficiency and Accuracy
The drilling speed and exceptional accuracy of the Sandvik DT821C Jumbo stems from the combination of high-performance RD520 / RD525 rock drills, robust booms, advanced drill string guides, and an advanced control system. Accurate positioning using any navigation methods and precision in drilling maximizes the round performance because of significant reduction in over-breaks / under-breaks. This leads to direct savings in the costs of additional spraying or secondary blasting.
Control system and Instrumentation
The control system on Sandvik DT821C offers a wide range of practical features which greatly improve the drilling accuracy and performance. Features include an automatic percussion feed control that optimizes drilling pressure level with the pre-set limit values, hinders over and underfeeding, and enhances the life of rock tools and the rock drill.
The noise and vibration insulated FOPS cabin loaded with a high level of instrumentation, provides ergonomic and extremely comfortable working place with excellent visibility. The operator makes a smooth ride on the DT821C even when working in the toughest of terrains.
Furthermore, Sandvik drill steel, various retrofit kits, ready-made maintenance kits and genuine spare parts supported with 24x7 services, ensure trouble-free drilling all the time and allow you to maximize productivity.