Under the Contract (No.: 7/WSD/02), InnoPipe has to replace and rehabilitate the fresh and salt watermains of about 5,000 m in length and of diameters ranging from 80 mm to 750 mm within 18 months in the Sham Shui Po area. As the existing water mains are located beneath busy streets, such as Apliu Street, Kweilin Street and Pei Ho Street in Sham Shui Po, a trenchless method, together with the conventional cut-and-cover method, is employed for the work to minimise excavation in the busy streets and thus reduces disturbance to the shops nearby and the neighbourhood.

InnoPipe uses an innovative technique, known as Paltem-HL Method that is developed by Ashimori Industry Co., Ltd., to rehabilitate the watermains. The Paltem-HL is a patented cure-in-place pipe lining method that requires little or no excavation for rehabilitating pressure and gravity pipelines including portable water, gas and sewer. Only two pits are required to be excavated at two ends of the watermain to be rehabilitated. After pipe cutting and cleaning, the PAL-Liner coated with adhesive is inserted into the existing pipe by inversion (turning inside out) using air pressure. The PAL-Liner is bonded to the host pipe to form a close-fit pipe after hardening of the adhesive. End rings are finally used at the pipe ends to ensure that the PAL-Liner is firmly connected with the host pipe. Training is provided beforehand by Ashimori to transfer the technical knowledge on the installation process and the operation of machinery to InnoPipe staff .

The project commenced on 15 January 2003 and its brief sequence is as follows:

1. Investigating on existing pipe alignment
2. TTA implementation and pit excavation
3. Installing temporary by pass, if necessary
4. Pipeline suspension
5. Pre-cleaning CCTV inspection and pipe cleaning
6. Post-cleaning CCTV inspection
7. Pipeline rehabilitation by Paltem-HL Method
8. Post-lining CCTV inspection
9. Pipeline testing
10. Re-connection

In the project, a high pressure jetting machine and various tools are used for pipe cleaning while inversion equipment and a resin mixer are employed for the rehabilitation work. The major constraints governing the execution of the project include the interface with other Drainage Services Department?s (DSD) projects in Sham Shui Po, a congested working area and a tight construction programme. Due to several DSD's and other projects progressing concurrently with the rehabilitation work, InnoPipe has to maintain close liaison with other contractors, and compromise with them in some cases to keep disturbance to the community to a minimum.

Besides, it is well-known that Apliu Street, Kweilin Street and Pei Ho Street are popular tourist streets in Sham Shui Po crowded with a lot of hawkers and passer-by. InnoPipe has to coordinate with relevant government departments to facilitate the progress of the works. For example, InnoPipe sought assistance from the Food and Environmental Hygiene Department in temporarily relocating some hawker stalls to facilitate the excavation of the pits. Also, due to a large number of passer-by at day time, InnoPipe obtained a noise permit from the Environmental Protection Department to conduct the works at night, if necessary.

Time constraint is another difficulty encountered by InnoPipe. The congested working area and various restrictions imposed by local authorities resulted in InnoPipe taking about three months to apply for the necessary construction permits. Hence, only 15 months are left for the construction works. Together with the interface with other DSD?s projects, InnoPipe has to carry out the works around-the-clock to catch up with the working schedule.

Up to mid February 2004, about 40% of the works is completed. The project is now at its peak with about 20 workers working on the site and it is anticipated to complete on schedule in July 2004.

采用崭新
Paltem-HL方法
修复深水�那�的水管

新维通有限公司（下称新维通）于二零零三年一月十五日取得和兴建筑有限公司一份价值一千七百八十万港元的工程合约，负责更换及修复深水�那�的食水及咸水管道。

根据合约（合约编号：7/WSD/02）规定，新维通需要在十八个月内更换及修复深水�囊淮�的食水及咸水管道，管道的总长度约五千米，直径由八十毫米至七百五十毫米不等。由于现存的水管位于深水�牡姆泵�街道下，如鸭寮街、桂林街及北河街，新维通弃用传统的明挖随填方法，采用了崭新的非开挖技术施工，避免在繁忙街道上进行开挖，减低工程对邻近商户和社区的影响。

新维通应用的创新技术名为「Paltem-HL」，由日本Ashimori Industry Co., Ltd.研发而成，并已取得专利，主要用于修复受压及重力水管，如食水管、气体管道及污水道。其好处是毋须进行挖掘工作。此技术只需在修复管道的两端各自开挖竖井，然后切除竖井底部的一截水管，再以气压推动回转机器，把涂上胶粘剂的补垫推入受损的水管内。待胶粘剂硬化后，补垫便会和修复的管道紧贴在一起。重新接合的管口会套上尾环，以确保修复后的管道与原有管道能紧密接合。施工前期，所有施工的工程人员须预先接受严格技术转移训练，以掌握安装程序和操作机械的技巧。

工程在二零零三年一月十五日展开，其施工程序为：

1. 勘测现时水管的位置
2. 临时交通改道及开挖竖坑
3. 铺设临时输水管
4. 切断水源
5. 清洗水管前的闭路电视探测及清洗水管
6. 清洗水管后的闭路电视探测
7. 采用Paltem-HL方法修复水管
8. 修复水管后的闭路电视探测
9. 水管测试
10. 重新接驳水管

新维通采用了高压喷射泵和各种工具清洗管道的管嘴，并且使用了专用的回转设备和树脂搅拌机进行修复工作。

整體來說，工程考驗主要來自三方面，包括與渠務署的工程範圍重�铡⑹┕きh境狹窄及工程緊迫。

由於渠務署有多項工程同時在深水�膮^進行，而且有部份工程與管道修復工程的施工範圍重�眨�新維通需不時與各個承建商保持緊密聯繫，並且在有需要時與他們互相協調，以減輕工程對鄰近社區造成的影響。

另外，鴨寮街、桂林街和北河街是深水�挠忻�的繁忙街道，常常擠滿各式各樣的小販和途人。新維通需要與有關的政府部門合作，務求工程進展暢順。例如新維通需得到食物環境衛生署協助臨時遷移部份小販攤擋，才能開挖豎井。另外，由於日間街道有許多途人，為免工程對途人進成不便，新維通需要取得環境保護署發出的噪音許可證，才可在晚間施工。

時間緊迫是另一個新維通需處理的問題。由於施工環境狹窄，新維通花了三個月取得各種施工許可證書，剩餘的施工時間只有十五個月；加上修復工程與渠務署的工程範圍重�眨�工期更見緊迫。新維通為了按時完成整項工程，有需要時安排二十四小時施工。

截至二零零四年二月中，新維通已完成約百分之四十的工程。現時正是建造的高峰期，有二十多名工人在工地施工。整項工程可望在二零零四年七月按時完工。