Extremely compact, maintenance-free: innovative flow control technology

By Michael Rogers

Field trial for the world’s first diaphragm-free gas distribution pressure regulator
Field trial for the world’s first diaphragm-free gas distribution pressure regulator (photo: Oxford Flow)

As an innovative developer of pressure and flow control equipment, Oxford Flow can trace its engineering roots to jet turbine research, when the company’s CTO, Professor Tom Povey worked to develop a pressure regulator that could meet his needs.

Neil Poxon, Oxford Flow CEO
Neil Poxon, Oxford Flow CEO

Energy Northern Perspective spoke with Neil Poxon, Oxford Flow’s CEO, who described how the Professor’s insights have been applied, first to fit the needs of public water distribution facilities, and now to demanding industries including oil and gas.

Less is more
Flow control valves from Oxford Flow are nearly maintenance free, Poxon says, “One of the core innovations around our products – in fact the innovation the professor originally came up with – was to do away with the diaphragm completely. All the complexity around the diaphragm, 10 to 20 moving parts, is replaced with one, single moving part – an actuator piston.”

“There’s multiple advantages to replacing the diaphragm and conventional technology with a single moving part, which means the design is truly 100% axial flow,” he continues. “And this flow dynamic means that there’s no zones of high velocity around any of the seals, so it’s protecting the seals from erosion as well.”

This innovation was driven by dependability, Poxon stresses, “By taking the conventional 20 moving parts down to one, it promotes reliability, and we essentially market our products as maintenance-free valves for that reason. First, there’s no need to replace the diaphragm, and apart from the cost of the diaphragm itself, there’s the cost for the maintenance, labour, and everything else that goes with it.”

Reduced maintenance requirements lead to savings for spares, Poxon explains. “Some of the conventional technologies in this area require that every four years the whole valve is removed from oil and gas and is serviced at the manufacturer’s facility and put back in place. And that means the operator has to have stand-by valves to be able to replace these with when they are out for service.”

“Because our design eliminates those requirements, OPEX-wise there’s a unit cost saving which is quite dramatic,” he says. “Due to reduced maintenance and better reliability, we see this in the water sector as around an 80%-plus OPEX savings using our valves versus the incumbent. And we see no reason why it couldn’t be at least as good for oil and gas as well.”

In addition to cost savings, size and weight are an advantage as well. “Our products are typically 10 times or more lighter than the conventional technology,” Poxon says. “And that has a huge impact on civil works and offshore facilities, in particular minimising size and weight requirements.”

Innovation evolution
“The initial traction was established in the water sector, primarily utility water, with a novel version of our innovation, which is the world’s first 100% polymer valve,” Poxon continues.

Oxford Flow’s core innovation, a pressure reducing value (PRV) with a direct sensing piston actuator instead of a diaphragm, was, at first, launched to water networks (photo: Oxford Flow)
Oxford Flow’s core innovation, a pressure reducing value (PRV) with a direct sensing piston actuator instead of a diaphragm, was, at first, launched to water networks (photo: Oxford Flow)

“Transitioning to a steel valve for gas to oil and gas has been quite challenging, meeting standards and requirements. Also, oil companies have told us that more than 50% of the reasons why these valves fail is because of the stem, which is also a fugitive emission risk. So, the biggest challenge for us was designing a valve with no external mechanical moving parts – stem or actuator – and in doing so, we removed the fugitive emission risk at the same time,” he adds.

The evolution of Oxford Flow’s technology has continued, applying these innovations to the design of a stemless and actuator free multiphase flow control valve. Poxon explains that the added benefit is a dramatic savings in cost: “This multiphase axial flow valve – that meets all of the oil and gas specifications – looks like a conventional control valve without the actuator on the top. And then consider that the actuator is typically as big as the valve as well – and as expensive as the valve itself. So, by doing away with that actuator, we can provide a valve that is half the size, all told, and we are targeting half of the cost.”

In the field
Last January, Oxford Flow began a field trial for its steel diaphragm-free gas distribution pressure regulator valve, funded by the Network Innovation Allowance (NIA), the UK National Grid programme that promotes technological innovation.

“We have almost completed a big NIA project, where SGN – Scotia Gas Networks – is the industrial sponsor,” says Poxon. “And that project basically culminates in the field trials of the steel gas valve. We’ve completed one field trial and almost completed the second. The whole project should be wrapped up by February, and so we are now in a position where we will soon formally launch that that product for gas. And it’s not just for gas distribution, it’s for any gas type of application.”

Oxford Flow’s new IM gas regulator valve set to increase reliability and reduce costs for operators in the gas distribution, power generation, industrial gases and oil and gas sectors (photo: Oxford Flow)
Oxford Flow’s new IM gas regulator valve set to increase reliability and reduce costs for operators in the gas distribution, power generation, industrial gases and oil and gas sectors (photo: Oxford Flow)

The valve’s size and weight savings were evident during the trials, says Poxon. “At the beginning of the trial as they were commissioning our valves, they were removing the conventional valve using a crane assembly and a jig. They actually used a crane – this is a 4-inch valve, and it has this huge stem on top of it. And then they were installing our product into the line by hand.”

“That’s the scale of the difference in size and weight for just a 4-inch valve, so you can imagine the impact considering the bigger valve sizes,” he adds.

Full package
“I always like the idea that we’re just touching on the fact that Oxford Flow is not only a valve company,” Poxon responds when asked about what the future holds. “Although most of our products are flow control valves, we do have ancillary products too. We’re working in particular around intelligent systems, smart valves, and cyclonic separators, for example, that separate black powder from gas streams, which is a notorious challenge for the industry.”

“And then we have the intelligent add-ons to these products – automated control and data transmission. On all of these valves we have the capability to fully automate and tie in with the SCADA packages by various different mechanisms, such that the valve can be completely autonomously operated from a control room or from a Web browser – including dataflow, pressure, temperature, water quality, position sensing – that data can flow back to the control rooms so the operator can have enough information available to control the process,” he continues.

“We have systems to generate power remotely, so we can take a gas stream with a very low pressure drop across a valve, and using a new, innovative and patented process, we can generate power at site to allow for valve control, if a valve’s automated, and data logging.”

“So, the future of the company is to maintain and grow its momentum on the utility sectors and industrial process, particularly the utility markets. And at the same time, we will very proactively continue to develop the oil and gas market because that’s where the true high-value and value creation for the company will come from, especially given what we’ve achieved.”