Automatic control to solve tough challenges

Atlas Copco China - Lin Chun-Hung, project manager

Lin Chun-Hung, project manager of Section C2 Renshui Tunnel Office of Continental Engineering Corporation

Works at the Renshui Tunnel on Su-Hua Highway (Taiwan Highway No. 9) were started in June 2014. They involved excavating a main tunnel 2,997m long, 18.2m wide and 11m high and a 3,000m long, 4.5m wide and 5m high emergency escape tunnel. The tunneling work is expected to be completed in July 2018. According to Lin Chun-Hung, the project manager of Section C2 Renshui Tunnel Office of Continental Engineering Corporation, the Renshui Tunnel has favorable geological conditions, and excavation will be carried out mainly through drill-and-blast. Unlike most other tunnels, the Renshui Tunnel has a very large cross-sectional area, averaging 158 square meters and reaching a peak of 250 square meters in the expansion section, which poses the greatest challenge to tunnel construction. In addition, the relatively great length of the tunnel makes it extremely prone to collapse incidents, affecting the project schedule. 

 

Endeavoring to minimize downtime and enhance borehole quality and efficiency, Continental Engineering Corporation thoroughly researched similar products available on the market, and selected Boomer XE3 C three-boom drilling rig equipped with RCS. RCS can help rig operators monitor and control drilling parameters, and records rig operating status, events and errors for follow-up analysis. After operating the system for a while, Mr. Lin commented, “RCS improves drilling precision and stability as well as reduces the time needed for training new operators. It gave us strong support in meeting the challenges involved in the Renshui Tunnel Project.”

Outstanding efficiency and drill durability

Atlas Copco China - Boomer XE3 in operation

Boomer XE3 C three-boom drilling rig in operation

Boomer XE3 C three-boom drilling rig delivers outstanding performance in terms of both drilling quality and efficiency. Assuming that every sector requires 160 blast holes, each measuring 45mm in diameter and 2m in depth, it takes Boomer XE3 C 2.5 hours to drill the holes in a sector. It operates at a net perforation efficiency of 128m/hour (all three booms combined); factoring in the time needed for piton insertion, slagging, support erection, shotcrete spraying and maintenance, its gross perforation efficiency averages 20m/hour (three booms combined). From this 17 June (project launch) to 20 December, a drilling footage of 497.3m was completed at the main tunnel of the Renshui Tunnel, fully meeting the client’s schedule for construction progress. Given the fact that only two workers are required on each shift to operate Boomer XE3 C, labor cost has been significantly reduced. 

 

Continental Engineering Corporation equipped Boomer XE3 C with original drills produced by Atlas Copco to achieve maximum production speed and efficiency， and can really sense the important role of grinding in ensuring extended drill durability. After being ground 2-3 times by an Atlas Copco Secoroc BQ3 grinding machine, the average service life of a drill bit can be prolonged by 30% to ~700m.

Intimate service for a successful model

Advanced technology, highly durable drilling tools and dedicated customer service – this is the assessment Continental Engineering Corporation has made of Atlas Copco. Despite being a first-time customer for the Boomer XE3 C and contracted services, Mr. Lin has no doubt that he made the correct choice, “Despite the relatively higher cost of the service contract, judging by the services we get, it’s definitely worth it.”

 

Vincent Chou, Atlas Copco’s on-site service engineer, best qualified to speak on this matter, said: “We stand by 24/7 to serve the client as and when needed. Since Boomer XE3 C is the first computerized drilling rig purchased by Continental Engineering Corporation, the operators lacked experience. We offered training to them in groups on how to master the equipment as quickly as possible. Additionally, I was involved in checks and maintenance service on the rigs myself at least once every day, each session lasting 2-4 hours.” Chou said that even when the rigs are in normal operation, he stays at the site watching through drilling operations, so that any potential issues leading to breakdowns could be identified and solved within the shortest time possible. 

 

As the old Chinese saying goes, “if you put your heart to it, you can break up metal and rocks.” With hard work, the Atlas Copco Boomer XE3 C Drilling Rig made a good start in the Renshui Tunnel Project at Section C2 Su-Hua Highway (Taiwan Highway No. 9). More importantly, this is a landmark in the use of modern computerized rock drilling rigs in tunnel construction in Taiwan.