Another item“The best in the world”Bridge

Eight large-tonnage rotary drilling rigs of XCMG

Deep-sea sandstone drilling

Bear that sea thoroughfare with solid pile foundation

Recently，Key Control Project of Changjiu High-speed Railway with XCMG Rotary Drilling Rig——The pile foundation construction of the main tower of the South Branch of Ganjiang Highway and Railway Bridge is under way.，Xugong was assembled at the project site.XR460D、XR550DAndXR580HDEight ultra-large tonnage rotary drilling rigs，Be responsible for the construction of main pier pile foundation of the bridge。

The south main bridge of Ganjiang Rail-cum-Road Bridge is a prestressed concrete asymmetric cable-stayed bridge.，The main tower isHType，The tower is 108 meters high.、The total length is 510 meters，ForThe world's largest span 350 kilometers per hour single-tower concrete girder cable-stayed railway bridge。The main pier pile foundation of the south branch main bridge consists of 23 piles with a diameter of 2..Composed of 8m cast-in-place bored piles，Pile length 66m，The deepest pile can reach 80 meters.，Pouring by tremie method。

The rotary drilling rig needs to penetrate into the 15m overburden layer.，Deep into silty clay、Fine sand、Sand and gravel、Highly weathered argillaceous sandstone 17m，It is then embedded in weakly weathered argillaceous sandstone for about 49m.，Difficulty in drilling and hole forming during construction、The risk of hole collapse is high，It puts forward extremely high requirements for power head and drilling tools.，And that drill accuracy of the rotary drilling machine is require to be high.，Precise pile-forming。

Speed up in the dry season is another major difficulty of the project.，The project manager said：

“At present, the difficulty of the project is to seize the dry season of Ganjiang River.，Complete the construction of all pile foundations and bearing platforms，Make sure that before the rainy season，The construction of the main body will not be affected by the rising water of the river，The construction of 18 pile foundations should be completed by the end of December.。”

XugongXRSeries super-large tonnage rotary drilling rig，He has always been an expert in conquering hard rock deep piles.。

XugongXR460D、XR550DAndXR580HDAll adoptedLarge triangle structure，Hard rock is more stable，Equipped with double slewing reducer，Ensure that the hole is not deviated，Equipped with intelligent control system，The verticality of the drilling mast can be automatically adjusted and displayed.、Pressure-adding stepless adjustable、Bottom-touching protection and other functions，Various power head modes such as standard mode and rock-entering mode，Graded pore-forming，Ffectively ensure that stability of the hole wall and the hole forming quality in the pile foundation construction proces。

Current project site60%AboveAll rotary drilling rigs are XCMG products.，Pile forming speed of XCMG rotary drilling rigOne pile in 6 days on average，The person in charge of the project site is confident of completing the construction period on time.。

Takeoff rainbow、Across the Ganjiang River，XCMG Rotary Drilling Rig Will Continue to Develop Bridge Foundation Construction，Tamping the foundation and erecting the steel and iron beam of a powerful transportation country。