On the Roof of the World

In the construction of the Ya'an–Nyingchi section of the Sichuan–Tibet Railway

The "two tunnels and one bridge" are the most difficult of all

At the construction sites of the Sejila Mountain Tunnel and the Dadu River Grand Bridge

XCMG rotary drilling rigs roar and sing

The construction of the Dadu River Grand Bridge, the only grand bridge on the newly built Ya'an–Nyingchi section of the Sichuan–Tibet Railway, seems to carry a different significance. From 1935, when the Red Army forced a crossing of the Dadu River and seized the Luding Bridge, opening a breach in a natural defense line the enemy regarded as impossible to escape and carving out a passage for the Central Red Army to march north, to today's construction of the Dadu River Grand Bridge on the Sichuan–Tibet Railway, this route has undergone earth-shaking changes.

From Red Army soldiers crossing the perilous river bare-handed to modern builders equipped with advanced manufacturing equipment, Made in China now has the strength to "make the sun and moon shine in a new sky." XCMG large-tonnage rotary drilling rigs XR580HD, XR600E and XR700E stand towering, turning their drill pipes into sharp weapons and engraving the hardcore strength of China's foundation construction machinery onto this natural chasm.

The Dadu River Grand Bridge is a long-span suspension bridge with a span of 1,293 meters, including a main cable span of 1,100 meters. The project is large in scale, adopts a suspension bridge structure, has a long main span and is subject to many constraints, placing high demands on construction.

For the two pile diameter types at the main piers—3.5 m tapering to 2.5 m and 3 m tapering to 2.5 m—and pile depth requirements of 60–70 m, XCMG large-tonnage rotary drilling rigs each play to their strengths.

The XCMG XR600E adopts a box-type slewing platform structure with double large vertical plates, making operation more stable and reliable. Its modular multi-position power head is designed separately for soil and rock operations, and the power head's rotation speed can be continuously adjusted in normal mode and rock-drilling mode, improving construction efficiency and reducing operator fatigue.

The XCMG XR700E can achieve the world's maximum drilling depth of 160 m and can be equipped with the XRT2100 full-slewing drilling rig for full-casing green, mud-free construction. In the plateau canyon at an altitude of more than 1,600 meters, it has so far driven 20 piles consecutively, averaging one pile every 1.5 days, with the deepest pile reaching 67 m.

In November 2020, the Dadu River Grand Bridge project of the Sichuan–Tibet Railway broke ground. The project requires pile foundation work to be completed by the end of December 2021. XCMG rotary drilling rigs have accelerated and improved the project's efficiency with outstanding performance, and completion is expected as early as the end of October 2021, shortening the construction period by two months.