North American Special - Trenchless International

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SPECIAL FEATURE April 2009 - Trenchless International Made in China by Kate Pemberton The global HDD market is a dynamic and expanding area. A new innovative market emerging from the east is set to challenge the dominance of the traditional manufacturers. The prolonged and extensive period of construction growth in China has enabled the country’s huge cities to modernise utilities such as water, wastewater, and telecommunications. Above ground construction has been achieved so rapidly that in many of China’s populous cities no-dig construction is the only practical method to install and repair the necessary supporting infrastructure. The use of HDD has been a factor in the development of a growing export market. Despite the slow down in China’s growth rates, the trenchless industry continues to gain momentum domestically. Chinese companies are finding success exporting machinery such as HDD rigs to the rest of the world. The HDD market In the past Chinese ‘knock-offs’ have been dismissed as unreliable, based on quality concerns. However, international partnerships, increased technological capability and lower costs are combining to create a market for the Chinese product. HDD Broker General Manager Bob Martin spoke to Trenchless International regarding the international HDD market. Mr Martin said that historically the North American market has been unwilling to accept Chinese manufactured equipment. Mr Martin said “Even the Chinese do not readily accept their own equipment, acknowledging the quality shortcomings and instead opt for the much more expensive US-manufactured drills.” However, this situation is changing. The impact of the global financial crisis is reverberating around the world. Project managers are looking for ways to cut costs while still maintaining the high standards expected in the industry. The economic downturn is not the sole reason for the increase of exports of Chinese manufactured drills. Mr Martin said there has been a marked increase in the quality of the Chinese product. “Demand for cheaper, simpler machines is increasing at a very fast pace as the demand for work remains constant but the money available to purchase decreases,” he explained. Chinese rig manufacturers exhibiting at the Mosow International No-Dig 2008. East meets west HDD rigs have been manufactured in China for over a decade. The Chinese domestic market has grown as people discover the benefits of trenchless solutions. Professional relationships between non- Chinese and Chinese companies have also encouraged an improvement in the quality and production capabilities of Chinese machinery manufacturers. Hanlyma, founded in 2003, is one of China’s leading manufacturers of HDD rigs. Hanlyma spokesperson Jerry Liang said that rapid growth and strong branding has culminated in the company supplying 30 per cent of the domestic market. The first American HDD rig was imported into China in 1988. Ten years later the first Chinese rig was created. Mr Liang said that prior to 2003, 90 per cent of the HDD market was shared between prominent international companies including Vermeer, Ditch Witch and Case. Mr Liang said that over the last five years Chinese rigs have come to dominate the Chinese domestic market, accounting for almost 95 per cent of market share. There are currently more than 200 contractors engaged in trenchless construction in China, using more than 2,000 HDD rigs, approximately 700 of which were introduced in 2007 with the biggest HDD rig in the world now in China. As the quality of the rigs available has improved, Chinese companies have begun to find success on the global stage. Mr Liang said that Chinese HDD machines are well priced to compete in the international market with high quality technological capabilities. In 2008, Hanlyma exported 112 rigs, or approximately 44 per cent of their product. Another concern levelled at Chinese HDD manufacturers in the past is a lack of after sales service. Hanylama is currently focused on increasing the quality of after sales service. To facilitate expansion and service capabilities, the company has sales and service centres in countries including Australia, Russia, India, Malaysia and Turkey. The feedback from international customers had been positive. Mr Liang said that customers were satisfied by the good performance and quality of the Chinese built machines and the level of service available. In addition, Chinese companies are now endeavouring to increase their international presence through attending Trenchless conferences such as the Moscow No-Dig Conference 2008 and the Trenchless Australasia Conference September 2009. International perspectives and relationships We asked Mr Martin how he thinks people perceive the quality of Chinese rigs, “Not surprisingly, there are two qualities that seem to pervade the perception of Chinese equipment, those being ‘cheap’ and ‘low quality’. “Interestingly, from my own research and experience with newer Chinese manufactured rigs, I would only partially agree with those statements,” he said. Mr Martin concurred with Mr Liang’s opinion on the technological advancements Chinese rig manufacturers have achieved. “The more successful Chinese companies have made great advances in quality control, going so far as to source the major components for the HDD drills from North America.” Mr Martin listed motors, hydraulic components, pups and gearboxes as the parts most likely to be sourced from outside of China. “The resulting machines are more expensive than their purebred Chinese counterparts; however they offer much of the reliability of North American machines while still being significantly cheaper.” Mr Martin concluded from his research that these Chinese rigs are, on average, 50 per cent less expensive than a US-manufactured drill with comparable pullback capacity. Mr Martin did acknowledge though, that Chinese drills will be slower and offer fewer options than the major manufacturers. The Chinese machines are still in a process of building a solid reputation. Some Chinese companies, recognising the advantages of expertise and longevity, have sought to forge partnerships with established international companies. American companies are taking advantage of the increasing technical capability and lower manufacturing costs of the Chinese HDD manufacturers. In May 2008, Charles Machine Works (CMW), manufacturer of underground construction equipment Ditch Witch, signed a joint venture agreement with Tu Xing Sun No-Dig Tech of Beijing, China. CMW said that Tu Xing Sun is considered to be a leader in the manufacture and distribution of HDD systems in China. CMW CEO Tiffany Sewell-Howard said “This venture allows us to strengthen our position in China and other emerging markets.” The Shanghai Gudeng Construction Machinery manufacturing company, specialising in HDD, exports to Russia, Ukraine, Pakistan, India, Malaysia and Singapore. Their HDD technology recently received first place in the construction machinery branch of the China Quality Association’s awards. In order to expand the business, the company is establishing a joint venture in Malaysia to be called Jiangsu Gudeng Construction Machinery Assembly Group. The factory will have a production capacity of 300 HDD machines and 100 static pulling machines per annum. Developing the industry The development of the industry is also being assisted by the development of professional organisations. The China Hong Kong Society for Trenchless Technology or CHKSTT was established in 1999 and is one of the societies affiliated with the ISTT. Other societies in the Greater China region include those in Shanghai (SSTT), Beijing (BJSTT), Guangdong (GDSTT), and Taipei (CTSTT). Chinese HDD companies are beginning to produce reliable, cost effective machinery for both the domestic and international markets. Companies such as Hanlyma are focusing on after sales customer service and forging mutually beneficial international partnerships. The export of Chinese manufactured HDD rigs is set to continue as companies build their brands through improved quality for the less complex and less expensive machines. SPECIAL FEATURE April 2009 - Trenchless International 18 19
projects April 2009 - Trenchless International Reconstructing pipes in Wajima City By Masatoshi Kasukawa, Komatsu. Translated by Kyoko Kondo In Wajima City, Noto Island Japan, an earthquake caused the destruction of more than 16 km of sewer and agricultural pipes. To restore the pipes, a new trenchless technique was applied – the IM-Rebirth method can crush and remove existing reinforced concrete pipes and install new pipes along the same trajectory. The IM-Rebirth solution successfully overcame some unexpected difficulties to reconstruct approximately 1.2 km of sewer pipeline, the first pipeeating project of this scale to be carried out in Japan. The entrance of the Wajima city building. The flag says “Hang in there!” following the earthquake. The sewers to be reconstructed were located at the end of the downstream, immediately before the Monzenmachi wastewater management center. The pipeline was buried below National Route 249 at a depth of 4.2 metres down to 6.3 metres. The Hakkagawa River runs along the road and there were many cracks observed at the river wall. It was predicted that the whole area was affected from the ground deformation due to the earthquake. Many existing manholes had been dislocated due to the water pressure. The type of soil was water-bearing stratum, which seemed to have increased the warping of the ground. Even from above ground, it was clear that the sewers had suffered displacements. Outline of damaged pipes sagging. Choosing the right technology After considering the level of sagging and displacements, CIPP was deemed an inappropriate method to restore the sewers, therefore the choice was made to reconstruct the whole pipe. There were two options for reconstruction; open cut and trenchless. Open cut was rejected as the pipeline was too deep to excavate. Moreover, taking into account the ground water level and economic efficiency, the trenchless method was selected as the optimum solution. An alternative was to install a pipeline next to the damaged pipe using the standard microtunnelling method. However, microtunnelling needs disposal treatment of the existing sewers including removing manholes up to the 1.5 metre level. Considering all of these factors the pipe eating method was selected. The types of existing sewers were; 1. Humes pipe for open cut construction 2. Humes pipe for microtunnelling construction – including stainless steel collar 3. A Humes pipe as a casing pipe – PVC pipe of 200 mm diameter was placed inside. Pipe eating method A, from the current reconstruction method listed in the guideline issued by Japan Microtunnelling Association, was chosen to crush and remove the existing damaged pipeline (pictured). Reconstruction method The IM-Rebirth method The IM-Rebirth method is based on traditional machines, such as Slim-Ark TA50 and the Iron Mole series, which can excavate hard cobbles and rocks. The difference between these machines and the IM-Rebirth method is the cutting head with a special cutter, spiral or gear type, which can crush the existing reinforced concrete pipes and reinforcing steels bars. This method not only crushes the existing pipe but also removes the pieces. This results in a newly installed pipe. The cutter head can also crush railroad ties and stainless collar used between the pipes. The jacking head torque is high enough to crush the hard cobbles and rocks located around the pipes. The starting shaft can be very small. For pipe diameters of 250 mm up to 300 mm only a 2 metre shaft is required, and for pipe diameters of 350 mm up to 500 mm a 2.5 metre shaft is required. A cutting head after the excavation test. Reconstruction methods from the Japan Microtunnelling Association Static crushing and jacking method Dynamic crushing and jacking method Rotating/ crushing and jacking method A type B type Pull-out and jacking method Scope of application Existing pipe diameter: up to 1000 mm Diameter of new pipe: 250 – 1,000 mm Total length: 150 metres – depending on condition Existing pipe type: hume pipe, (for open-cut , jacking pipe with SUS collar), clay, PVC, PE, FRP Ground conditions: standard soil, sand gravel, base rock layer Applications: same diameter to same diameter, reducing diameter, enlarging diameter, adjusting trajectory. Crashed pieces at the test excavation. The IM-Rebirth method was selected because of the cutter head's ability to crush reinforced pipes and SUS (stainless) collars. However, as the project progressed, it was revealed that a spacer of 5 mm thickness was used inside of the casing pipe for placing VU 200 mm. To negotiate this problem, an excavation test was carried out before the actual construction commenced. The test showed that although the jacking speed had slowed down greatly and the cutting face was abraded a little from the excavation, the machine can drive forward despite the presence of the spacer. Some parts of sewer were completely out of service and temporary bypassing was carried out. Several drives were progressing at the same time; therefore a well-planned bypassing was necessary. Bypassing of the current live sewers was carried out by using the proven technique for long-distance sewers called Mr. Autobypass. The Mr. Auto-bypass has working records of 17.5 km and out of this record, 3 – 5 km were bypassed simultaneously while constructing several, mainly opencut drives. Shaft construction The existing manholes were damaged from liquefaction and needed to be replaced. Therefore, the spaces for replacing manholes were used as departing and arrival shafts. In 300 mm diameter pipes, a shaft diameter of 2 metres was used and for 350 – 400 mm pipes a shaft diameter of 2.5 metres was used, which contributed to reduced construction costs. Infilling existing pipes The existing pipes suffered displacement, sagging as well as some infiltration of waters and surrounding soils. It was anticipated that the area around the machine excavation could be a void and cave-ins might occur after the construction. To avoid this problem, infilling of existing pipes was carried out in order to prevent cave-ins. The filling material was a cement-mortar. Removal of pit-head The waterproofing equipment and sheet piles used for the first installation, buried in place, needed to be removed. The open-face jacking of 1,000 mm diameter was used to remove this equipment at the beginning of the drive and then removed manually. The cutter head The cutting head, equipped with the special cutter to crush reinforced pipes, progressed smoothly along the planned paths. At the peak, seven jacking machines were driving simultaneously. The crushed pipes, taken in by the jacking machine, consisted of materials such as reinforced steel bars, SUS collars, waterproofing rubbers and PVC pieces. Railway ties placed below the pipes were also found in small pieces. The most difficult section of excavating the 400 mm casing Humes pipe and 200 mm VU pipe plus spacers was carried out successfully, although the driving speed did not reach the planned rate. The discharged soil was treated as industrial waste since it contained steel pieces, concrete, VU and others. In total, 21 drives were carried out and there were no serious problems requiring the driving be halted. The special cutter equipped at the cutting face had some ablation from cutting spacers, but was able to continue the drive. The pipe eating [and jacking] method is normally used to replace aged pipes with new pipes. However, this construction was carried out to replace existing pipes damaged greatly from the earthquake. Many of the damaged pipes had suffered displacements and sagging and some sewers had lost function completely. Komatsu’s first pipe-replacing technology was achieved in 1995, the time of Great Hanshin-Awaji earthquake, proving that this method could be used for replacing pipes that have experienced large displacements. Smooth bypassing had also contributed a great deal in making the whole reconstruction successful. Above: Excavation test. Left: A spacer. projects April 2009 - Trenchless International 20 21
Page 1 and 2: In this issue | Canada | USA | Japa
Page 3 and 4: Dec Downey Istt Chairman Trenchless
Page 5 and 6: EXECUTIVE DIRECTOR'S REPORT John He
Page 7 and 8: Pipes & People Prime Horizontal pip
Page 9 and 10: Trenchless in Toronto The 2009 Inte
Page 11: Events ISTT International No Dig 20
Page 15 and 16: Insertion of the liner takes about
Page 17 and 18: Alleviating flooding in Ashbourne S
Page 19 and 20: obotics April 2009 - Trenchless Int
Page 21 and 22: Risky business by Roderick Lovely a
Page 23 and 24: Deterioration Factors Distress Indi
Page 25 and 26: environment Supplying the community
Page 27 and 28: Record SWP down under Interflow, an
Page 29 and 30: north america April 2009 - Trenchle
Page 31 and 32: north america is a biaxial stress,
Page 33 and 34: disc cutter heads to work through t
Page 35 and 36: “We had a very tight window to ge
Page 37 and 38: Undersea HDD rescue in Saudi Arabia
Page 39 and 40: ADVERTISERS INDEX SUBSCRIPTION FORM

North American Special - Trenchless International

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