Process Management Renewal Rings

Tech Tip: Process Management Renewal Rings – When is the Question

Acceptable Part

Unacceptable Build Up

Renewal rings or build up welds are sometimes the necessary evil of our business. In a perfect world every converter core we receive would be a nearly perfect factory specimen. Of course perfection is what we strive for and not always the reality. We have all had the “critical core” that the new cut open operator took just a bit too far. Now what? Or maybe the better question is when. Do you look at the parts with one eye closed and hope there is enough overlap and let the core work through the process only to find out at the welder that it won’t fly, or do you build it up just because experience tells you it’s pretty close? If you are a one man operation you probably know when to make the call. Add a couple of employees and you will have a couple of different opinions and potentially a couple of different results. With an initial investment of less than $100.00 and a notebook or a simple spreadsheet you can create a database that will take the guess work out of “when” and provide the consistency to eliminate this question. Take the hundred dollars and purchase a low cost Dial Height Gage. Durability is probably a little more valuable than accuracy here. With a notebook or spreadsheet create a table with the following headings:


Part Number
Minimum Height Maximum Height
 1234  2.900  
 234  2.720  2.910
 3456  1.740  1.900

As you produce your product, list your part numbers. Over time, measure the Impeller or cover to establish the minimum acceptable heights for your parts and note it next to the appropriate part number. Once those heights are established simply set your height gage and you can quickly measure each part (see photos) as it comes by to determine its direction in the rebuild process. Next you will notice a column for maximum height. You may be wondering why that’s an issue. Well there are a couple of scenarios that are important here. One potentially negative scenario is if you are building up or putting rings on covers and bonding frictions in those covers there is little room for error. It is easy to bottom out on the ring and not get adequate pressure on the friction therefore creating a subpar bond. A positive scenario is if you are using CNC machines or considering using them these numbers are invaluable when it comes to programming. Either way, once you have your parameters set you can work with both eyes open.

Jeff Stuck
Certified Transmission