SUBJECT : The problem with pump standards 2-4

A quick check of existing pump standards will reveal that there are a variety of them. The list includes:

There are at least two problems with these standards:

Unfortunately standardizing the length of pumps ,prevented manufacturers from designing short shafts that were not prone to the bending problems associated with low cost A.N.S.I. and I.S.O. design pumps, operating off of their best efficiency point (B.E.P).

Here is a list of some of the modifications you should make to your standard A.N.S.I. or I.S.O. pump, if you want to get good mechanical seal and bearing life. Unless you are prepared to upgrade the pump, seal and bearing life will always be less than desirable

WHAT TO MODIFY

In addition to these modifications, here are some recommendations that will help to insure good seal and bearing life.

Pumps equipped with a "repeller" and some sort of static seal can usually be converted to a good mechanical seal. The problem with the repeller design is that in most of the configurations, the seal faces are designed to open when the pump is running and then close on any solids as the pump stops. The rule with mechanical seals is a simple one, "keep the seal faces together." Don't open them on purpose.

® E I Dupont Dow elastomer

For information about my CD with over 600 Seal & Pump Subjects explained, click here  

Link to Mc Nally home page