One Year Anniversary of the XR550D's Next Line: "The World's Largest" Rotary Drilling Rig Performs Differently

Construction Site

How big is "the world's largest"? XCMG XR550D rotary drilling rig is composed of a telescopic crawler chassis, large-diameter slewing ring, full single-row winch rope, self-falling collapsible drill collar and telescopic drill pipe, and is supported by the pile foundation. According to the project site manager Mr. Ke Yonghong, “The rotary drilling rig was assembled by borrowing one 100-ton, 70-ton and 25-ton vehicle crane. Its height was over 30 meters and the weight was 185 tons. With a diameter of 30 tons and a maximum drilling diameter of 3.5 meters and a maximum drilling depth of more than 100 meters, the proudly standing group has an eye-catching position in the main tower. It has a large horsepower and plenty of power and can adapt to most hard rock deep piles."

Why did the project department first introduce this "giant"? What problem does it solve? It is understood that the Jinsha River Bridge, an ornate high-speed project, is a key control project for the entire expressway project, and its construction technology is difficult, the construction process is complex, and the geological conditions are influential. There are 32 2.8-meter pile foundations on the Lijiang River at the Jinsha River Bridge. The total length of the pile is 1,728 meters, of which the longest pile length is 65 meters, and the total amount of concrete is 11,000 cubic meters. The amount of pile foundation works is large and the project duration is tight. Yang Renjie, head of the project department of the project department, said: “We have used the original main bridge foundation design survey data to show that the natural compressive strength of the basalt in the main tower location is around 130 Mpa. According to past construction experience, the 460 type rotary drilling rig can fully meet the drilling requirements. The hole progress requirements can be confirmed on site, and the actual geological survey data shows that the rock strength is generally much higher than the design, and the maximum intensity exceeds 330Mpa, which brings no small challenge to the project construction.”

What is the concept of rock formation intensity exceeding 330 Mpa? Yu Xiuquan, who is responsible for the site of the pile foundation team, stated: “Since 1995, I have been doing more than 20 years in the construction of super-long bored piles. I have never seen such strength. Rock formation, when I got the coring test result, I couldn't help but shuddered and I was really taken aback. Having done the test, we will take out the pellet sample to beat the ordinary I-beam and the I-beam recess goes in. 5mm, core material is unscathed, and it can be imagined how hard the strength of this pile foundation is."

A majestic appearance on the construction site

“The problem must be solved as soon as possible!” Wang Lianbin, who has always been a rigorous project leader, had eaten the scale and was obsessed with the irony. He must erase the “difficult disease”. The construction plan for the previous period has been rejected, coupled with the high project construction quality requirements and the time required for the construction period. In this case, they continued to wonder at the site of the main tower for several days and wanted to solve the problem. According to the communication between the design institute and the owner, combined with the project geology and actual construction requirements, the project department has conducted in-depth research and comparison analysis, and has quickly got a look. In the shortest possible time, it has come up with detailed pile foundation construction plans and pile foundation construction equipment. It was imminent to enter the site and eventually decided to introduce a “big guy” rotary drilling rig with high construction efficiency.

XCMG's basic technology and service personnel continuously improve the construction process together with customers

At present, the drilling of the pile foundation of the main tower of the Jinsha River Bridge is proceeding in an orderly manner according to the construction plan. The first-level core drill with 1.2 diameters is drilled, and the minimum footage speed can be kept at 0.45 meters/hour. XCMG's basic technology and service personnel are continuously improving the construction process together with customers.

At the close of the first anniversary of the departure of XCMG XR550D Rotary Drilling Rig, we wish the XR550D will continue to perform different highlights during the construction of the project pile foundation!