Lifetime performance assurance

There are over 2 million miles (3.5 million km) of pipelines used around the world to transport fluids across vast distances and even over mountainous regions. Designing and maintaining the pumps that are integral to these systems to run at optimum efficiency keeps running costs to a minimum and can also help to improve the operator’s sustainability credentials. Pumps that operate at peak performance have improved reliability and less downtime for maintenance: the key is implementing the best design for the application.

Current projections for the next five years forecast significant pipeline extensions in Asia to meet ever-increasing demand for oil, gas and petroleum products. At the same time, further additions to the existing pipeline network are expected in North America, Africa and the Former Soviet Union to meet both export and domestic demands.

Counting the cost

At the heart of every pipeline pumping station are the pumps, which need to be expertly specified, designed and installed to ensure that operations run as efficiently as possible. For any new-build pipeline, the efficiency and energy demand of the pumps will dictate the size and cost of the electrical infrastructure that needs to be installed to support the system.

Once a pipeline has been built and commissioned, the running costs are predominantly made up of the energy bills for operating the pumps. Therefore, finding the most efficient pump design for each station is essential to minimising the costs throughout the service life of the equipment which could extend up to thirty years or longer. At the same time, the financial value of the fluids and the sheer volumes being transported, mean that any unexpected downtime can have a very significant cost in lost revenues.

More recently, the global focus on greenhouse gases has led to the implementation of carbon taxes, which also affect pipelines directly – the greater the energy usage, the higher the carbon tax. This change in policy is causing more renewable sources to be used to power pipelines where possible, making them more cost-effective both financially and ecologically.

To keep operating costs to a minimum, the pumps need to perform as close to their best efficiency point (BEP) as possible. For those running in the megawatt range, the consequences of working outside the preferred operating range (POR) can be very significant. The fluid is no longer in equilibrium and the flow becomes disturbed; prolonged operation can lead to reduced reliability and a shortened mean time between failure (MTBF).

Design from the ground up

The first step in the journey to optimum efficiency is calculating the most effective layout in terms of location for the pumping stations, and how many need to be constructed to deliver the required performance. Involving the pump designer at the earliest possible stage is important in achieving the most cost-effective solution. Optimal efficiency not only delivers the lowest running costs for the operator, it also offers the lowest carbon footprint, which should be considered by all businesses today.

In an application where a 1% improvement in efficiency can save over US$1 million/yr in running costs, an optimised design is crucial to achieving the best overall solution. For this reason, bespoke pump designs should be considered for each station. The annual savings over a ‘standard’ pump far outweigh the additional investment in the optimal design and manufacturing of a custom pump.

Building to a plan

For new-build projects, understanding the energy requirement for each pumping station has a direct effect on the cost of the power infrastructure that needs to be installed. Each station is equipped with pumps of sufficient size to transport the fluids to the next station. Pump design is central to the number of pumps required as well as the total power consumption. The total number of stations, pumps in each station, and the size of the equipment all affect the overall plan. With a design life in excess of 30 years, optimising running costs should be the prime objective, and this includes taking account of future operating conditions. For example…

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Read the article online at: https://www.worldpipelines.com/special-reports/05102023/lifetime-performance-assurance/