久久亚洲国产成人影院-久久亚洲国产的中文-久久亚洲国产高清-久久亚洲国产精品-亚洲图片偷拍自拍-亚洲图色视频

Global EditionASIA 中文雙語(yǔ)Fran?ais
Business
Home / Business / Industries

Urbanization drives demand for tunneling machines

Xinhua | Updated: 2019-10-11 10:15
Share
Share - WeChat
Engineers assemble a tunnel-boring machine on an open working field owned by China Railway Hi-Tech Industry Co Ltd in Zhengzhou, Henan province. [Photo provided to China Daily]

Orders for homegrown equipment soar on growth in large infrastructure projects

BEIJING - A super large tunnel boring machine (TBM) measuring 15.03 meters in diameter has begun an underwater tunneling project in Shantou city, in South China's Guangdong province.

Measuring 130 meters long and weighing 4,800 metric tons, the slurry TBM, with a maximum thrust of 25,000 tons, can cope with complex terrains such as soft silt and hard granite bedrock, according to its manufacturer the China Railway Engineering Equipment Group Co Ltd (CREG), one of the leading TBM suppliers worldwide.

Under 10-bar pressure from water, air, earth and slurry, the machine will bore a tunnel 3,048 meters long at a depth of 20 meters.

Its cutter head smashes the bedrock into small pieces, which are mixed with stones and sediment and then delivered out of the tunnel.

China's TBM demand has increased alongside the country's rapid development. Many large infrastructure projects such as urban subways and railways that traverse mountains or waterways often require the technical and operational support of TBMs.

The TBMs can excavate tunnels using a circular cross section that drills through a variety of soils and rocks, and they seamlessly lay down concrete segments to build tunnels, subway tubes and sewer lines.

The China Association of Metros said that by the end of June, 34 Chinese mainland cities had subway lines. Jinan and Lanzhou are welcoming their first metro lines.

The fast expansion of rail transit has boosted demand for TBMs, and domestic demand accounts for 60 percent of the world total, CREG estimated.

The 18 manufacturers of TBMs have a combined annual output of about 1,000 units, said Song Zhenhua of the China Construction Machinery Association (CCMA).

TBMs are getting larger as tunnels become wider to integrate utilities such as railways, highways, water supply and drainage pipes, telecommunication and power cables.

Safety is the top priority, though, no matter how large or complicated the projects are.

A 4,760-meter-long tunneling project with vehicle freeways and subway rail lines is now under construction in Jinan, in East China's Shandong province.

The tunnel is equipped with fire hydrants, broadcasting devices, emergency phones and video monitoring devices to ensure evacuation within six minutes in the upper vehicle freeway and 30 minutes in the lower subway rail lines in case of an emergency, said project designer He Yingdao.

Separately, China's largest slurry TBM with a diameter of 15.8 meters started work on a project in Shenzhen, South China's Guangdong province, in August.

Over the past few decades, China relied on foreign tunneling expertise, with Beijing bringing in experts for its first subway lines in the late 1960s, said CCMA secretary-general Su Zimeng.

In 2008, China's first independently developed earth pressure-balanced TBM made its debut.

With around 30,000 precision components and mechanical engineering, electric, sensing, information and dynamic technologies, a TBM is considered a gauge of a country's level of equipment manufacturing expertise.

In the past decade, China's TBM industry has seen great progress, with those products exported to more than 10 countries and regions for projects such as subways, highways, railways and in water conservancy.

About 70 percent of components and parts of Chinese TBMs are domestically made, said Song."Our products are cheaper than those produced by other countries and excellent after-sales service is also our commitment."

By the end of June, CREG had received 916 orders and manufactured 842 TBMs, a level that is five times higher than five years ago.

Manufacturers and experts are working to promote the repurposing of TBMs. The machines are specifically tailored in different shapes and diameters for each project.

"It's a pity that such high-end equipment is hard to be reused," said Su Zimeng. He suggested the tunneling industry agree on unified standards, such as the maximum width and height of tunnels, so the machines can be used in more than one project.

Top
BACK TO THE TOP
English
Copyright 1995 - . All rights reserved. The content (including but not limited to text, photo, multimedia information, etc) published in this site belongs to China Daily Information Co (CDIC). Without written authorization from CDIC, such content shall not be republished or used in any form. Note: Browsers with 1024*768 or higher resolution are suggested for this site.
License for publishing multimedia online 0108263

Registration Number: 130349
FOLLOW US
CLOSE
 
主站蜘蛛池模板: 国产人成精品 | 国内外成人免费在线视频 | 黄色在线视频网 | 国产免费久久精品久久久 | 国产精品欧美日韩 | 一级看片 | 免费视频男女 | 欧美一级情欲片在线 | 日韩亚洲国产综合久久久 | 欧美一级鲁丝片 | 国产一级精品高清一级毛片 | 99国产精品视频久久久久 | 加勒比色久综合在线 | 免费一级a毛片在线播 | 国产精品日韩欧美在线 | 91精品手机国产在线能 | 成年女人毛片免费视频永久vip | 亚洲国产欧美在线成人aaaa | a黄毛片| 欧美大片aaaa一级毛片 | 亚洲精品一区专区 | chinese情侣真实自拍 | a毛片a毛片a视频 | 扒开双腿猛进入喷水免费视频 | 亚洲美女综合 | 亚洲精品高清在线 | 色播亚洲视频在线观看 | 国产午夜精品理论片久久影视 | 台湾三级香港三级在线理论 | 欧洲成人全免费视频网站 | jul-179在线中文字幕 | 色爽爽爽爽爽爽爽爽 | 色综合加勒比 | 狠狠色综合久久婷婷 | 国产黄网 | 亚洲欧美一级视频 | 国产高清一级视频在线观看 | 亚洲天堂网在线观看视频 | 午夜无遮挡怕怕怕免费视频 | 特级毛片全部免费播放器 | 亚洲欧美日韩在线一区二区三区 |