INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Jobs

Seal leaks prematurely at High Pressure but holds at Low pressure

Seal leaks prematurely at High Pressure but holds at Low pressure

(OP)
Hi,

I would like to ask for some opinions. I had a double-seal that was leaked at high pressure, however, it holds (didn't leaks) at low pressure. The seal runs with plan 53B (barrier system), and the inboard seal-face materials are SiC-SiC:

1. When i perform hydrotest, whereas the seal barrier area was pressurized at 30barg, whereas the product side is 0 barg , it didn't show any leakages.
2. However, when i do dynamic test, i pressurize the seal at 18 barg (product side), and pressurize the barrier area at 20 barg (which make the differential pressure of 2 barg), the seal leaks at the inboard.
3. Then i lower down the product pressure to 5 barg, and then reduce the pressure at barrier area to 7barg, then the seal didn't show any leakages at the inboard.

Anyone has any idea on why this situations occured? Does the concave/convex seal faces has anything to do with this?

Thank you for your time

RE: Seal leaks prematurely at High Pressure but holds at Low pressure

It should have an air test from the vendor, and it should be used during performance testing of the pump. It is not typical to hydrotest mechanical seals.

What is a "dynamic test", is the seal rotating?

RE: Seal leaks prematurely at High Pressure but holds at Low pressure

Need more data about the seals. Your statement about the high pressure leaking and low pressure not leaking is confusing at first. I read this as the high pressure has a low pressure difference between the two sides and the low pressure has a high pressure between the two sides. If this is the case then one reason is that the pressure difference is deforming the seals and resulting in a better seal. This is not unusual.

RE: Seal leaks prematurely at High Pressure but holds at Low pressure

What is the seal face config? concave or convex or dead flat?

RE: Seal leaks prematurely at High Pressure but holds at Low pressure

check flatness of seals.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close