I’m excited to bring you our first guest post by Tim Fabian. Tim is a renowned waterjet expert, well versed in everything from machine design to daily operation. It is my pleasure to have him as our guest blogger for this week. Without further ado…. Tim Fabian.
I’ve had such fun reading these posts that I decided to contribute one myself.
Some of us waterjet users have been here. A critical job for big customer #1 is getting picked up in the morning and your pump just lost pressure. You quickly tear into the pump and see the problem, a damaged o-ring. Easy, you think, “all I need to do is replace this inexpensive part and I’ll be up and running right away!” It’s natural for all of us to think this. After all, who can argue the logic behind getting up and running as fast as you can and saving a few bucks while doing it? Pause here. While the temptation to selectively change specific parts as they fail may seem like the right thing to do on the surface, the numbers don’t lie. The impact to your productivity and profitability will indeed be significant….just not in the direction you might think.
Take the example above, but this time replacing all the wear components.
You have already invested the time to tear down the pump, the tools are already in your hands, and the machine is already off line and not making any money. But this time you choose to install the entire seal rebuild kit and added a pair of check valve kits for good measure. Now you stand a very good chance of seeing 500 to 1200 hours (depending on pump type and other factors) of maintenance-free pump operation for just a few minutes of additional labor and downtime. On the flip side, by just changing that simple o-ring, you have spent less than $5 in parts. You’re coming out ahead, right? While that may be true for now, take into consideration the likelihood of an additional failure within 100 hours. In a 60k Intensifier, there are four seals packings, two back up rings, and two check valve kits (somewhat different for a HyperPressure pump or a direct drive rotary pump, but the idea is the same). If you constantly repeat the same process of replacing only the component that failed, you will reduce the cost for each repair, but drastically increase the frequency of repair. So, let’s use some conservative numbers. Over the same 500 hour period we compare rebuilding an intensifier pump with a full kit, or selectively replacing individual components every 100 hours. This example is on a 60,000 psi intensifier:
|Proactive Replacement||Selective Parts Replacement|
|Labor||$120 (1 repair x 3 hours@ $40/hr.)||$500 (5 repairs x 2.5 hours@ $40/hr.)|
|Lost Up-time||$450 ($150/hr. rate x 3 hours)||$1875 ($150/hr. rate x 12.5 hours)|
|Intangibles||1 headache, better machine reliability and on-time delivery to your customers||5 headaches, machine reliability and product delivery to customers suffers|
|Total $ Impact||$1,064||$2,575|
You can clearly see that once we apply some realistic numbers to these two maintenance methods, we are far better off by proactively replacing even those parts that are seemingly still working fine.
While more money to the bottom line is really great news, particularly if you’re the business owner, maybe the most notable part of this equation is the fact that you’ll enjoy many more hours of reliable and consistent operation. That’s less breakdowns at 4:00pm the day before you go on a family vacation, and less time trying to figure out how you are going to meet that big morning delivery for Customer #1. I think that’s something that all of us can celebrate.
Thanks for reading.