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Expert: Pipeline collapse proves urgent need for air valves

The catastrophic collapse of a pipeline at a $10 million (€8.8m) project in Central America is clear proof that current procurement of air valves needs to be urgently reviewed, according to IVL Flow Control.

Craig Stanners, director of IVL Flow Control, part of Ham Baker Group, said: “This latest incident was actually caused by not having any air valves at all, which was a disastrous oversight by the consultant.

“In an increasing number of cases it is not the end-user or the contractor at fault. It’s a lack of understanding from consultants who don’t seem to understand that when you are putting water into a pipeline or draining out due to a burst, air must be let in – and let out,” Stanners said.

According Stanners, the vacuum created by negative pressure in a system, caused by no air valves or the wrong type of air valves, is enough not just to destroy plastic pipelines, but tough metallic materials too.

He said that the “ludicrous recommendation” by the consultants for the unfortunate Central American project to make do without air valves probably initially “saved” around £7,000 (€8,906), to which he commented: “What an oversight.”

Unfit products

“In the UK, there is a plague of cheap plastic air valves in the ground. These valves are a single, air-out only function, costing around £70. Instead, two-way valves (for air-in and air-out) should be installed, but because they’re closer to £170, procurement departments or consultants think they’re doing a great job with savings,” Stanners lamented.

“Perhaps they could explain then why in the US alone there is now $346 billion worth of failing assets in the ground. I don’t call that much of a saving.”

Stanners said he was horrified to be quoting on one recent project when the asset manager had to admit that although the municipal company knew they had air valves, they did not know exactly where – only that the contractor had used “a load” left over from a previous job.

Subsequent failures with poor tap pressures was already producing numerous complaints from consumers, dragging down the concerned water company’s reputation.

“In an age where anyone could use Google to get an idea of topography it seems unforgiveable that some consultants aren’t even specifying air valves to be installed every 500m on just a straight length of pipe,” Stanners concluded.

“And it’s madness too for those who do specify to then cut corners with cheap or unsuitable air valves.  It is time to install the right, long-lasting product and stop adding to the stockpile of failed assets buried in the ground.”