SAFETY FIRST: HYDRAULIC CYLINDER TEST TO FAIL 1

[BEMPE16524]

I just want to share with all how safety is very important.
We were instructed to service an old hydraulic cylinder from one Client XXX. The working pressure is 250 Bar and test to 1.5 times.
During extend, at around 320-350 Bar, BANG!!!
The gland pop out. The thread were sheared off. Luckily no incident.

Now, for the next test after re-pair, need to add more safety features. Thinking of covering the perimeter with solid counter weight.

 

[chicopee]

The hydraulic cylinder would have two ports, right? one port for extension and the second for retraction, am I correct so far? If the fluid on the retraction side of the piston was blocked from let's say a closed valve to the pump as you extended the piston, could that have caused your problem?
The pumps that I used to be involved were Enerpac and these pumps would develop pressures up to 10,000psig and I remember one particular case about 20 years ago when ironworkers did not follow the double acting pump set up diagram properly by omitting the hose connection to the retraction port of the cylinder causing the ball check valve to shoot out and severely injured one of the ironworkers. So yes, you are very fortunate that no one was injured during your test.

 

[BEMPE16524]

Yea... am thinking to use manual hand pump enerpac too. but not sure if can build up the pressure to 375 Bar as the counter balance is set to 250 Bar. Maybe need to pump a bit faster.
We shall see by this week.

 

[chicopee]

Contact Enerpac for a suitable pump. In my opinion, an electric hydraulic pump would be more suitable.