Pressure gauge which is removable - connect in line, only when needed
- when doing something which does need a measurement - a test or a tensioning activity. Has hydraulic couplings and can be there in-line, or can be absent.
Question - would one pump and one cylinder, a 50Tonne 50mm stroke single-acting, be enough for now? Strategy completed by --- get two pressure gauges, one to 700+Bar, one to say 100Bar, so can accurately read off the pressure for both high-force and low-force tests?
Can you think of a solution to a problem of recording the maximum pressure at which the sample broke?
When I built custom industrial test stations I used a Greenlee hydraulic knockout set to punch holes in steel boxes for controls and conduit. The combination of a heavy cylinder and hand pump on opposite ends of a stiff springy hose is impossible to fully control with only two hands, and the free end hits hard when it falls. Even when working on the floor the pump or cylinder tended to flip over hard enough to damage an attached gauge.
I'd say that the pump, cylinder and gauge are enough to get started, and the modular Porta-Power system is easy to expand later as needed. In my steel scrap collection is a press-like rectangular frame someone made from 1.250" hydraulic piston rod joining two drilled steel bars. Do you have a thread-cutting lathe and milling machine to make similar fixturing? Messing with hydraulics quickly took me beyond what a bandsaw, drill press and welder could do, although I bought all the high pressure fittings.
I had to machine a retainer for the low profile hydraulic cylinder of the
10,000 Lb force gauge I added to my sawmill, and repair the pressure gauge on a tire inflater that a springy hose pulled off the sawmill when I was away.
I assembled a cheap and simple data logger for slowly changing signals from an old laptop and meters like this:
my solar power application the optical isolation between channels is vital. If you acquire a pressure sensor with an analog voltage or current output the meter's .CSV data file can be read into a spreadsheet and easily converted to match your calibration measurement.
There are inexpensive DRO (distance) scales available to retrofit machine tools but I've never tried to connect one to a computer.
As first a chemist and later an electronic test tech I learned how to make measurements to 0.01%, and also that there's no point trying to greatly exceed the accuracy of your worst instrument or the inherent randomness of your subject. In non-critical mechanical testing 5% accuracy is good enough, which might be 20% of the full gauge scale although higher than half scale is preferable.