April 19, 2023, "The world's first SUNWARD Super Rotary drilling Rig SWDM1280 promotion meeting" was successfully held. Nearly 100 customer representatives of pile foundation industry, technical experts and media journalists from all over the country gathered in Ningbo, Zhejiang to observe the construction process of super rotating drilling rig on the site of Xihoumen cross-sea Railway Bridge project of Yongzhou Railway. They sighed "super shock" one after another.

Super engineering traction super equipment development

As a leading enterprise of piling machinery, SUNWARD adheres to the concept of pioneering innovation, actively responds to the needs of the country, the market and customers, and develops various high-end, specialized and standardized innovative products. Coincident, it is the super project of Yongzhou Xihoumen cross-sea Railway cross-road Bridge that draws the development of SUNWARD super rotary drilling rig SWDM1280.

Xihoumen cross-sea Railway cross-sea Bridge is the world's largest span cross-sea cross-sea bridge, which sets many times the most at home and abroad. It is a key control project of the whole line of Yongzhou Railway. With large project scale, novel bridge structure and high science and technology content, it is a super cross-sea project challenging limits.

In July 2020, SUNWARD, China Railway Bridge Bureau and Wuhan Lecheng team, taking into account the pile foundation construction environment, pile type and stratum characteristics of Xihoumen cross-sea railway bridge, combined with the construction experience of offshore pile foundation projects such as "Shenzhen-China Passage", began to study the super rotating drilling rig and construction technology, and conducted 12 expert technical workshops in the early stage of the scheme.

In January 2022, under the leadership of SUNWARD chief expert He Qinghua, the research and development team has overcome many technical difficulties of large equipment in construction stability, loading and unloading convenience, riveting deformation of large parts, processing accuracy of large machine parts and other aspects, and the super rotary drilling rig SWDM1280 officially rolled off the production line.

How good is a super spin drill?

Super rotary drilling rig SWDM1280 maximum hole diameter up to 7 meters, maximum hole depth up to 176 meters, with SUNWARD's strong pilot research and development innovation ability, equipment for large bridge pile foundation, super deep, rock, disassembly and transportation, to create a number of key core technology, has obtained nearly 50 patents for invention and utility model patents.

At the promotion site, SUNWARD engineering engineer Bin Wu introduced the technical innovation of super rotary drilling rig in detail.

In order to solve the problem of difficult disassembly and transportation of super large equipment, double pin type power pin shaft is adopted to realize automatic loading and unloading of track side beam, stable construction and efficient transfer.

Abstract: In order to improve the stability of rotary braking and the accuracy of hole forming, the technology of braking force enhancement of rotary platform with large inertia was developed to solve the problem of shaking of rotary platform caused by large transient impact load during drilling in super hard rock stratum.

Aiming at the problems of reliability and machining accuracy of oversized and ultra-long drill pipe, the five-key and six-square-head drill pipe is invented, with reliable bending and torsional force transmission. Using refined seamless steel pipe and special radian key bar, it breaks through the control technology of large-length telescopic drill pipe key bar straightness, and the straightness reaches within 3mm.

In order to solve the problems of reliability and drilling efficiency in the construction of super-large and ultra-deep rock-socking piles, the inner ring positioning hob classification drilling technology is adopted. The dead weight and pressure are applied to ensure smooth drilling and high verticality of drilling, and the drilling efficiency is increased by more than 1 times.

In view of the adaptability problems of large pile mechanical engineering, the modular design concept is adopted to configure two sets of engine hydraulic system. The power system can be divided and combined, the chassis modular design can be wide or narrow, and the mast modular design can be high or low, so as to adapt to different engineering environment and pile type requirements.

In view of the construction cost and reliability problems of large piling machinery, it is equipped with large diameter, large length drum and 66mm large diameter steel wire rope to achieve a single row of 5 layers of machine lock rod, which not only has a large lifting ability, but also greatly extends the service life of steel wire rope.

It is with the support of these advanced technologies that the SUNWARD Super rotary drilling rig is equipped with the strength to conquer the offshore super-large deep pile.

Super equipment supports super engineering realization

In January 2023, SUNWARD Super rotary drilling rig SWDM1280 sets out for Yongzhou-Xihoumen cross-sea Railway Dual-Use Bridge. In February, by relying on advanced technology, stable performance and reasonable construction method, it overcame such difficulties as "strong wind, high wave, deep water, rapid flow and open rock", and drilled the first pile of pier No. 6, becoming the world's largest rotary drilling rig in actual combat, breaking the record of SUNWARDSWDM1000 rotary drilling rig.

"The foundation of No.6 pier consists of 8 bored cast-in-place piles with a design diameter of 4.5 meters, a design hole depth of about 60 meters, a depth of about 25 meters from the construction plane to the seabed surface, a thickness of about 10-15 meters in the covering layer of the pier foundation, and about 20 meters in the weak and breezy layer. "With a three-stage reaming process, the 4.5-meter pile can be drilled in about 54 hours, ensuring accuracy and improving efficiency." Zhu Jianxin, deputy general manager of SUNWARD, introduced on site that SWDM1280 has created the world record of the largest hole diameter of rotary drilling rig.

Guo Chuanxin, Secretary general of pile Machinery Branch of China Construction Machinery Society, said that he observed the construction operation of SUNWARD Super rotary drilling rig SWDM1280, which is the world's largest rotary drilling rig currently under construction, and the operation scene was very shocking! Really realized super equipment to help build super project!

Wu Kunxue, material and mechanical Department minister of Yongzhou Xihoumen cross-sea Railway cross-sea Bridge Project Department of China Railway Bridge Bureau also introduced the project in detail for the guests who participated in the activity at the site, he said: "To do a good job, we must first improve the tools. Considering the difficulty of drilling pile construction and the need for large equipment, we jointly developed SWDM1280 rotary drilling rig with SUNWARD, which demonstrated its strength in 4.5m construction and was recognized by our bridge Bureau."

At the same time, Yang Tianming, general manager of Wuhan Lecheng Construction Engineering Co., LTD., said, "From our relationship to now, I really feel the butler's service. From equipment manufacturing to technology, SUNWARD has been accompanying and helping us. SUNWARD's products, technology, especially the industry leader Mr. He, give us full confidence. Last year, SUNWARDSWDM1000 rotating drilling rig played a great role in the construction of Yanji Yangtze River Bridge. This year, SWDM1280 rotating drilling rig continues to help build Xihoumen cross-iron cross-sea Bridge, which will build piling machinery benchmarking project."

As a leading enterprise of pile machinery, SUNWARD has been constantly researching and developing innovation in recent years, using high and new technology to transform and improve traditional products, and developed a batch of super equipment such as super static pile press, super pile rack, super rotary drilling rig, etc., which has been applied in super projects at home and abroad, accounting for nearly one-third of the market share. Leading the pile industry toward the direction of standardization and centralization.

In the future, SUNWARD will further increase the investment in research and development, strive to achieve autonomy and control in the core key technologies, and devote more energy to the research of construction methods and the accurate grasp of user needs, with the spirit of excellence to do a good job in every link of the product, with better products and services to return consumers, leading the national brand to better on the international stage. To promote the development of pile machinery constantly make positive contributions. Editor/Xu Shengpeng