how many points would you suggest are done - 2.5?

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

I don't understand what you are referring to. If you don't give more details, you are unlikely to get any useful response.

Johnny Pellin

there are some say that if only one side of mech seal is replaced, there is no need to do 5 points check on that side. It means, when installing a new one, no need to do 5 points checking, install it right away. Is it true? or it is compulsory to do 5 points check for installing mech seal whether is on one side or both sides?

I don't know what you mean by a five point check. But, I will assume. If you replace only one seal on a double-ended pump, is it acceptable to leave the other seal in place and not do bore and face run-out checks to verify that the shaft is centered in the seal chambers. This is my take. If I have no reason to believe I have a problem with the other seal, I will probably not disturb it. If I check the seal chamber of the seal I am replacing and I find out-of-spec conditions for face or bore run-out, then I would pull the other seal and check it. If everything checks out good on the seal that failed, I will probably not touch the other seal.

Johnny Pellin

Conversely if this is one seal and you're talking about just replacing one half of it? What type of seal is it?

My mind jumped to 5 data points to establish performance and/or check the pump to the curve - no flow (deadhead), min rated flow, design point or some mid-point/max eff., max rated or just shy, and runout off the end of the curve

those 5 points check are:

1.) Radial deflection (0.005mm)
2.) Axial play/ Shaft End (0.1mm)
3.) Shaft run-out (0.05mm)
4.) Concentricity of bore (0.125mm)
5.) Squareness of face(0.125mm)

All checks must below those numbers (for axial play, its depend on type of bearings)

Let say outboard(O/B) or NDE side of seal is fail. So, we take out the seal and replace with new one. But, before installation, we normally do these 5 checks. So, back to my question, is it compulsory to do these checks if only 1 side of seal being install??

Thank for replying my question.. really appreciate it