Most anyone who has spent a day inside an industrial facility has seen a “Chicago Coupling” or as some may call it, a “crows-foot”, although they may have never heard the phrase that describes this device…
Photo Source: chicagocoupling.com
Having been raised as a safety engineer in the petrochem industry I learned early on that this was a [low-pressure] “water hose” of industrial-grade – NOTHING MORE. A few companies allowed this fitting to be used on LOW-pressure airlines (e.g. <150psi), but when used for low-pressure air it had to be PINNED and EQUIPPED with a “whip check”…
Photo Source: capitalrubber.com
So let’s discuss why this fitting is to NEVER EVER be used on a process containing a HHC/EHS – even for draining or venting!
First and foremost…
(NOTE: this is not a “Haywood” rule, this is using our First Line of RAGAGEP – manufacturer’s instructions; which I share all my sources directly from the manufacturer to make the case that we MUST STOP using this connector for work within our PSM/RMP processes)
In my 16 years in the chemical industry I crossed paths with VERY FEW safety and engineering professionals who suggested this fitting could be used with any chemical and even fewer who wanted to use the fitting on a Highly Hazardous Chemical or Extremely Hazardous Substance; but that was then and this is now and somewhere along that journey we flew of the track of basic chemical safety! Over the past several years I have seen this fitting used for every HHC/EHS you can think of and when I jump up and down screaming NO NO NO… the looks of disbelief are concerning!
The manufacturer states their MAWP on the fitting is only 150 psi. This is REGARDLESS of what the hose is rated for; the fitting and its attachment means is rated for ONLY 150 psi. This means that this connector can not be utilized on a process that has a pipe design of greater than 150 psi. This MAY allow this type connector to be used on some LOW VAPOR PRESSURE materials such as Caustic and some acids, but would never be permitted on an HHC/EHS due to their higher VPs.
These fittings are available ONLY in malleable iron, brass, and (316) stainless steel, so we MUST ENSURE the fitting is chemically compatible with the materials that will come into contact with the fitting. This does NOT include the compatibility concerns around the “gasket” that comes with the fitting.
BOTTOM LINE… this fitting is for LOW-PRESSURE water and air hoses – PERIOD! The company manufacturers these fittings for these two services ONLY. They offer no “Chemical Compatibility” information because they do NOT manufacturer this fitting for the use in any chemical applications.
And for the record… when I said these fittings were for “water hoses” this is NOT the kind of “water hose” I was referring to. With 27,000 members you know there has to be one smart_ss in the crowd and that he would be from the fire service! LOL
