New standards: jacking corrosion-resistant pipes in Singapore

The island state of Singapore accomplished the rise to a modern industrial nation in the ASEAN area (Association of Southeast Asian Nations) within a few decades. Today, approximately 5.5 million inhabitants live in densely populated Singapore, the majority in the capital, which bears the same name as the country. Strategic drinking and waste water management has been given high priority for a long time. The construction and expansion of a comprehensive sewer system had already begun in the 1950s as part of an ambitious infrastructure programme. Today, this Southeast Asian city state is also an international pioneer in the processing of waste water into drinking water. The slogan “use every drop of water more than once” is not only publicized in Singapore, but also rigorously implemented - already, more than one third of the wastewater is processed. Of course, very high demands are made for pipeline and sewer system quality. For example, only corrosion resistant pipes may be used for waste water disposal. The Bilcon Industries Company, based in Singapore and an established manufacturer of concrete pipes and structural precast components, takes the trend into account with the commissioning of an advanced Perfect Pipe production plant for lined concrete-HDPE composite pipes.

Robust and corrosion-resistant

Since November of last year, wet cast concrete pipes with consistent corrosion protection have been manufactured in various nominal diameters with the Perfect Pipe production system developed by Schlüsselbauer Technology for use in pipe jacking. Bilcon sets new standards in micro tunneling in the Southeast Asian civil engineering market, especially in terms of economical efficiency and sustainability of the pipe systems.

For Bilcon, the critical arguments for the selection of the Perfect Pipe system were firstly, the numerous product advantages of pipes manufactured from flowing concrete with consistent HDPE lining. In particular, they excel due to outstanding robustness and corrosion resistance. On the other hand, it was also due to the overwhelmingly positive experiences during the first reference project in Singapore in 2015, when Perfect Pipe was used. In the process, pipes in DN 300 nominal diameter from KTC Civil Engineering were installed in Tuas South Avenue using the pipe jacking process under a contract from the JTC Corporation. The result was so impressive for all participants that Bilcon immediately decided to start planning its own Perfect Pipe production plant in collaboration with Schlüsselbauer Technology. Implementation of this ambitious project required passing through all anticipated, local, product-specific tests and obtaining approval for installation of the new concrete-HDPE composite pipes. The strict testing procedure, which tested both individual Perfect Pipe pipes and the overall pipe system, was successfully completed in the summer of 2015. After that, nothing more stood in the way of making a start. Within a few months, Bilcon and Schlüsselbauer Technology built a state-of-the-art production plant at the headquarters in Singapore.

Bilcon Industries – technology pioneer

Bilcon Industries, the concrete pipe and precast component manufacturer, can look back on a long history of success. The company, founded in 1963 by Tan Leong Teck, has manufactured products for strategic drinking water supply and waste water disposal for over 50 years and has always been a pioneer in terms of technology and innovation. Lining conventional concrete pipes with synthetic materials to improve corrosion protection and the service life of waste water systems in general had already begun in the 1980s. While relatively brittle ceramic pipes were frequently used in the past, the trend is now clearly toward robust concrete-HDPE composite pipes, which are also distinguished by high resistance to all forms of chemical attacks.

With the selection of the Perfect Pipe production system, Bilcon took a significant step toward further modernization of its pipe production. In addition to the efficient production method, Perfect Pipe pipes are distinguished by an expected service life of over 100 years. On the one hand, this is secured by the internal corrosion-resistant Perfect Liner which is firmly anchored into a solid concrete shell. On the other hand, the consistent protection is guaranteed by the Perfect Connector made from resistant polypropylene which is also characteristic for the Perfect Pipe system. The pre-installed dual tilting lip gasket of the connector ensures maximum watertightness. Thanks to the Perfect Connector, the connection of pipes can be produced more quickly and therefore more economically than by welding synthetic pipes on the construction site. This leads to a significant increase in the installation rate in the range of no-men-entry nominal widths starting from DN300, while at the same time resulting in a reduction in installation costs.

Capacity increase due to innovative technology

Currently, Perfect Pipe jacking pipes are manufactured in the Singapore facility in nominal diameters DN 300, DN 400, DN 600 and DN 800 with lengths from 1 m and 2 m using vertical construction. Thanks to the production technology optimized by Schlüsselbauer, Bilcon is in a position to fill the forms several times each day, thus multiplying the output of finished pipes.

At the beginning of Perfect Pipe production, the HDPE film with a thickness of 2.5 mm is trimmed in accordance with the desired nominal diameter and length of the pipe and automatically welded into a watertight cylinder. The liner cylinder is then placed on a supporting core and the ends undergo an automatic thermoplastic transformation. Later, the Perfect Connector will be inserted into the expanded pipe ends that are formed in this way, without any reduction of the pipe’s cross-section.

The final outer contour of the pipes manufactured at Bilcon is formed by filling the vertically positioned  steel molds with self-compacting concrete. To ensure the dimensional stability of the corrosion protection, the liner is first fixed on a steel core. After concreting and a hardening process of approximately 12 h in the steel mold, the completed pipes are demolded. They are immediately ready for further use.

Maximum water tightness

The robust Perfect Pipe pipes manufactured from flowing concrete are outstandingly suitable for pipe jacking and have a decisive advantage for the trenchless method: The higher jacking speed due to quick and simple fixing of the tight pipe connection by using the Perfect Connector in the starting pit. The Connector is already assembled in the end of the pipe before a pipe is lowered into the manhole. Upon reaching the target shaft, the combination of Perfect Liner and Connector provides an enduring, corrosion resistant, ready-for-use, and above all, watertight pipe system without further work steps. Construction progress is not delayed by welding work on-site, together with its pre- and post-preparation times.

The Perfect Pipe pipes are delivered by Bilcon ready for installation, lowered into the starting pit, and result in a finished pipeline upon completion of each single jacking cycle. This increases efficiency in the production of enduring lines with the micro-tunneling proc-ess and the cost-effectiveness of driving methods.

Ambitious goals

In the medium-term, Bilcon Industries is pursuing the ambitious goal of achieving a leading position in product quality and manufacturing costs in the pipe jacking sector in Singapore and Malaysia. Initially, an expansion of available pipe geometries and further nominal diameters is planned to ensure this undertaking. In addition to the headquarters in Singapore, locations are being planned.

“Schlüsselbauer Technology’s manufacturing system allows us to make high-quality jacking pipes with different nominal diameters and continuous corrosion protection in a very short time”, says Tan Leong Teck, founder and CEO of Bilcon Industries. “In addition to the long service life, the integrated connectors for easy, safe pipe installation on the construction site speak particularly for Perfect Pipe. Paired with our manufacturing expertise, this results in an unbeatable combination of advantages that clearly lifts our system above competing products in the Southeast Asian market.”