Pressure transducer: nervous


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I bought a pressure transducer which measures up to 6000psi. The plan is (was?) to fit this to my bottle jack which I reckoned produced about 6000psi at its working limit.

I have since (coincidentally) seen a post on Reddit that led me down the rabbit hole of hydraulic fluid injuries. These are caused by very high-pressure fluid jets from failures of hydraulically-powered machinery. They cause incisions, in the first instance, and cell necrosis afterwards as the oil blocks up all the blood vessels and gangrene ensues.

I am not going to post photos here: they are gross. Google hydraulic fluid injuries or look at this report from the UK Health & Safety Executive. The report’s upper limit is 100bar (1450psi). The results are not at all pretty.

The AGAINST argument:

  1. I am inevitably going to try and test my jack to its upper working limit, and (given my welding abilities) there is inevitably going to be a pinhole resulting in a 6000psi death-jet.
  2. I recently sliced a tendon in my hand with a chisel and I am now wondering if frivolous ‘playing around’ with 6000 psi might not be such a great idea.

The FOR argument:

  1. Its a 6-tonne bottle jack. Where on earth am I realistically going to find 6 tonnes to lift? The heaviest things I have are my car and my house. My car is 1.5T at a push – you would only put half that into the jack.
  2. Manually cranking load into bottle jack is a slow process so ‘failure’ would be gradual (maybe???). And as soon as a failure occurs the pressure drops off (quickly???)

Well. It’s 2-2. I am going to think about it.

Afterthought

I once cut the tip off my big toe with a water blaster. It was like a hot knife through butter. The residential electric water blasters seem to max out at 2000-3000psi.

Don’t water blast in bare feet people!

That’s 3-2 against.