How a Polybutene pipe System made the grade during a recent refurbishment at the main campus at Ulster University.
PHAM Oct. 2003
The University of Ulster at Coleraine, Northern Ireland, is home to over 4,500 students, with nearly 400 actually living on the main campus. It has a full range of facilities including a large Sports centre, Student union and 13 separate accommodation buildings.
For such a large campus, an efficient heating System was top of the agenda during the recent development work that took place at the Coleraine site.Generally, campus type developments such as Ulster University use district heating with a central boiler plant delivering both heating and hot water via a pipe network to the separate campus buildings. This proves to be far more economical than having individual boilers in each building.
Historically, however, there have been many problems with so-called district heating. During the 1980s, for example, corrosion of the steel pipe network caused problems in outlying buildings which relied on the central boiler plant to provide both heat and hot water. The development of plastics, such as Polybutene- 1 (PB-1), has now made it far easier for installers to use and develop the technology behind district heating, resulting in a far more efficient and effective System.
The consultant engineer working on the Ulster University project was given a brief to specify a versatile material for the system that would not corrode and which did not require mechanical jointing. PB-1 proved to be ideally suited to the project,
offering many advantages over competitive and more traditional materials.
Going the distance
Firstly, PB-1 combines inherent flexibility with excellent creep and burst pressure resistance, ensuring long-life and ease of installation. This inherent flexibility means that pipes made from PB-1 are easy for installers to transport and fit over large distances and can be bent to a tighter radius without the need for preliminary tempering or additional jointing. This was a key consideration for the University as the installation needed to be as quick and straight forward as possible to avoid causing any disruption to the students. The installation was also made easier by the fact that the PB-1 pipes could be jointed using fusion welded Systems, a technique that most installers are now familiar with. Using fusion welding also results in a homogenous joint which cannot pull apart over time, making the original pipe even stronger and increasing its lifetime expectancy.
This was important for the university as they specifically wanted a material that would provide minimum maintenance requirements to ensure that there would be as little further disruption at the campus as possible.
Using PB-1 resulted in significant cost savings for the University. Fusion welding is by far the quickest and most effective way to joint district heating installations. PB-1 has also proved to be cost effective in terms of running costs given the fact that it is far more efficient against heat loss than steel, providing savings in excess of 40%.
The smooth bore characteristics of PB-1 also resulted in further cost savings as smaller pipe sizes could be used compared with the equivalent steel pipe size. The initial main pipe running from the boiler house was sized at 125mm and all the remaining distribution mains were in sizes of 110 mm and smaller. "There are many advantages associated with PB-1, including pipe flexibility, ease and speed of installation and the operational lifetime," explains Christian Engel, from The Polybutene Piping Systems Association (PBPSA), an association formed to underline manufacturers' confidence in PB-1.
"The University of Ulster had specific requirements for their district heating System and PB-1 proved to be ideally suited to the project, offering many cost savings to both the installer and end user. This case study is an excellent example of the benefits of PB-1 and shows how it can satisfy even the most demanding design criteria."
The PBPSA The Polybutene Piping Systems Association (PBPSE) is made up of market leaders from across Europe.