Barwon Water utilises kwik-ZIP spacers

kwik-ZIP product range is widely utilised around Australia. In the past few months, it has supplied products to McConnell Dowell and Barwon Water on a couple of major infrastructure projects.

kwik-ZIP product range is widely utilised around Australia. In the past few months, it has supplied products to McConnell Dowell and Barwon Water on a couple of major infrastructure projects.

Barwon Water replaces up to 20 kilometres of old and damaged pipes every year at an annual cost of around $4 million. This ongoing maintenance program minimises repairs, reduces supply interruptions and ensures continued water quality. Their service area is centred on the city of Geelong and the surrounding areas.

Where possible, pipes are replaced using trenchless technology, reducing the impact on residents and the local environment. Barwon Water selects one of two models for trenchless technology. One involves pipe bursting, where new pipes are pulled through the existing pipe system. This process sees the new pipes expand and crack the old pipes. The other option is directional drilling. A computer-controlled drill bores horizontally underground before pulling new pipes through the bore. It is the preferred method when a new alignment is needed.

Barwon Water reached out to McConnell Dowell, who have been utilising kwik-ZIP spacers on the projects to achieve this goal. McConnell Dowell used some of the HDX/HDXT casing spacers.

HDX/HDXT casing spacers

The HDX and HDXT casing spacers are flexible in their use. They can be used on many pipe materials, including steel, ductile iron pipes (DICL), high-density polyethylene (HDPE), concrete and mild steel cement lining (MSCL) carrier pipes. The casing spacers are designed for pipes ranging in outside diameter (OD) from 100mm to 1600mm and beyond. They can also handle a range of different annular clearances, given the range of runner heights available across the range.

The casing spacers help position the pipe properly within the casing or host pipe, ensuring centring and restraining or simply providing protection during installation. They are designed to be installed quickly and easily to support the carrier pipe, offering a low coefficient of friction wear pads. The pads resist abrasion from the casing or host pipe surface, assisting with installation. The anti-slip rubber pads also prevent spacer dislodgement during installation.

The load-sharing runner system maximises the spacer weight-bearing capacity while reducing point loading. At the same time, it minimises damaging vibration and movement transfer from the outer casing to the carrier pipe via suspension and the dampening effect.

The plastic spacer materials resist chemicals and oils, even when the spacers are immersed for long periods. Similarly, there are no metal parts to promote corrosion, and the lack of lead content makes them compatible with every potable water application.

The HDX/HDXT series casing spacer stations the pipe to promote even grout cover.  If the pipe is not to be grouted, the HDX/HDXT will support and isolate the carrier pipe plus its contents for the life of the installation.

Marshall DN560 HDPE Relocation Project

On a recent water main relocation project, McConnell Dowell utilised Kwik-ZIP HDXT-58W spacers to facilitate the slip-lining of a 560mm HDPE carrier pipe over a 260-metre run. This project also used a 1026mm ID RC Jacking pipe.

While not used on this project, Kwik-ZIP HDXT-58W spacers can accommodate its kwik-ROLLER wheels. These clip-on wheels are suitable for longer runs to minimise wear and reduce the friction coefficient.

Kwik-ZIP HDXT-58W spacers were installed as per Melbourne Water Retailer Agencies (MRWA) standards.  As the pipes would not be fully grouted after installation, the spacers are required to support the pipe and water for the life of the installation (Pipe weight – 83kg/m (empty) and 246kg/m (full)).

“Kwik-ZIP spacers were simple and quick to install, and the sales team promptly answered any queries,” said Paul Pomfret, Senior Project Engineer at McConnell Dowell.

South Geelong Station water main relocation project

On a similar water main relocation project, McConnell Dowell utilised Kwik-ZIP HDXT-58W spacers. It was to facilitate the slip-lining of a 660mm OD MSCL Steel Mains Sintakote carrier pipe over a 54-metre run. The project also used 800mm ID RCP casings.

“With limited room and unable to utilise our pipe rollers, we had some concerns about pushing the MSCL pipe. The 54m pipe would have been a challenge, but the Kwik-ZIP spacers allowed us to easily install using a 14T Excavator,” said Pomfret.

About kwik-ZIP spacers and centralisers

Kwik-ZIP’s spacer series caters to a range of carrier/casing pipe size combinations and provides flexibility to deal with project alterations. Kwik-ZIP spacers have no metal parts and are made from Kwik-ZIP’s engineered thermoplastic blend that is flexible, tough and has a low coefficient of friction.

Kwik-ZIP’s HDXT & HDX Series spacers have been appraised by the Water Services Association of Australia (WSAA). The WSA PS-324 product specification prescribes casings spacer requirements for correctly protecting carrier pipes when installed inside casings.

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