MadModder

Gallery, Projects and General => Neat Stuff => Topic started by: bry1975 on January 10, 2011, 03:22:57 AM

Title: 5,000psi or around 3,400metres pressure chamber
Post by: bry1975 on January 10, 2011, 03:22:57 AM
Hi chaps,

Just thought I would show my 5,000psi rated pressure chamber that I use for
pressure testing wristwatches down to below 3,000metres.

I'm sure some of you guys have seen or used Hydraulic calibrators/hand pumps at work.



Dimensions for chamber are O.D. 125mm, Bore 60mm, height 100mm. M14 grade 12.9 bolts
used when testing to 3,000metres.

(http://www.villagephotos.com/utils/image.aspx?u=2006-8\1202869\chamber1500.jpg)

(http://img.villagephotos.com/p/2006-8/1202869/Tunacan2.jpg)
Title: Re: 5,000psi or around 3,400metres pressure chamber
Post by: DavidA on January 10, 2011, 07:57:54 AM
bry1975,

I was trying to envisage the person who would be using a wristwatch at a depth of three Kilometer.

Just can't get my head around it though.

Dave. :scratch:
Title: Re: 5,000psi or around 3,400metres pressure chamber
Post by: bry1975 on January 10, 2011, 09:04:55 AM
Hi there,

It's purely for show and to satisfy watch collectors.

Bry
Title: Re: 5,000psi or around 3,400metres pressure chamber
Post by: Jonny on January 10, 2011, 04:51:31 PM
Some serious pressure there and nice work by the way.
Have you pressure tested the pressure tester? :lol:

Just wondering what you pump in, water or oil.
Usually fill cylinders with water and pump oil in from a modded 10000psi grease gun with clock or enerpack.

That looks a tasty guage.

Tell us more.
Title: Re: 5,000psi or around 3,400metres pressure chamber
Post by: bry1975 on January 10, 2011, 05:06:38 PM
Thanks,

The actual machining was contracted out as I didn't have a suitable lathe to turn the 127mm/5inch raw diameter, or the 60mm bore etc etc.

I've pressure tested the pressure chamber with the hydraulic calibrator shown the gasket finally gave away at 3,370metres probably due to the grade 12.9 bolts lengthening.  LOL and yes when the gasket blew it sounded like a gun shot.

I use plain tap water as it's a safe hydraulic media certainly wouldn't want to use hydraulic oil.

The pressure calibrator and gauge were bought from the US firm below at the time the US currency was close to $2 a £1 so some cracking deals could be had.

I generally test with kg/cm2 pressure units which is easy for depth conversion simply times x10 and you have metres in depth.

http://www.ptsinstruments.com/




Some serious pressure there and nice work by the way.
Have you pressure tested the pressure tester?

Just wondering what you pump in, water or oil.
Usually fill cylinders with water and pump oil in from a modded 10000psi grease gun with clock or enerpack.

That looks a tasty guage.

Tell us more.
Title: Re: 5,000psi or around 3,400metres pressure chamber
Post by: Jonny on January 11, 2011, 04:03:10 PM
Probably was the bolts lenghening and quite surprising how these things can stretch under pressure.

Have seen a few mishaps and very bad workmanship over the years, worst one was brass 1/4"BSP stud with a drilled and tapped 1/8" BSP up the inside with a 2Lb cylinder hangng off intended for 232bar. It blew at 70bar, moments before i was handling and looking down it. Some people just dont know what they are doing, glad you do.

Sir, do you want your watch testing for leaks :clap:
Title: Re: 5,000psi or around 3,400metres pressure chamber
Post by: bry1975 on January 11, 2011, 04:51:36 PM
 :jaw:

"Have seen a few mishaps and very bad workmanship over the years, worst one was brass 1/4"BSP stud with a drilled and tapped 1/8" BSP up the inside with a 2Lb cylinder hangng off intended for 232bar. It blew at 70bar, moments before i was handling and looking down it. Some people just dont know what they are doing, glad you do"



Thanks I spent quite sometime working out the possible pressure that could be generated so made sure the chamber walls and top plate was over built, chamber walls are around 32.5mm (1.28inches) and top plate 20mm (0.78inches).

(http://img.villagephotos.com/p/2006-8/1202869/Tunacan2.jpg)