Question: Do we need instrumentation-grade steel for an air intake valve?

kgradow1 is asking a question about general
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by kgradow1 | June 09, 2020 18:49 | #23805


I am trying to source parts to do a build test for the bucket monitor.

The original parts list calls for instrumentation-grade Swagelok parts:

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Does anyone know if I can swap these out for Home Depot parts?

It looks like I can get 3/8" compression couplings that are designed for air tubing for around $3 each, which would be a HUGE savings.

That said, I don't know if it would react differently or invalidate the air sample.



3 Comments

Hi! Tagging in a couple people who might have ideas: @guolivar @danbeavers @DavidMack

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You could probably use HD parts. It just depends on what you are sampling (corrosivity) and the threshold levels of your analysis. Ideally all "wetted" parts (anything that touches the sample) are stainless or teflon. However, brass or plain steel is going to work fine short term but can corrode long term and cause cross contamination.

Generally you wouldn't expect ambient air to corrode steel or brass but there certainly are places on earth that will happen due to local pollution.

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Ha! @kgradow1 so Check your community members' HVAC system. if the brass or other metal couplings have corroded, ask how often the resident has to replace the fittings.

I have seen people bring their corroded HVAC parts to public meetings to comment on Air Pollution permits. I think it was in Bogalusa, for the paper mill. As you know, air conditioning is an essential service on the Gulf Coast. Residents here pay a lot of mind to our HVAC bill, will probably remember the service fees for replacing the couplings on the unit outside their home.

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