We outsourced our pump manufacturing to China, due to our inability to find a manufacture in the US that could provide us the pumps at a price we could make a profit with. It’s not such an easy process. Good communications are critical, and so if you have to deal with a very small Chinese manufacturer you need a good go-between person who is fluent in both English and Chinese.
We were having a problem with a seal, well not us, the Chinese manufacturer. We were life testing the seals for the pump, as was the manufacturer. His seals consistently failed after a short time. Using the same parts and test procedures, (we thought), our tests were working out just fine.
I finally after weeks of going back and forth trying to find out the details I asked him to send me one of the “failed” seals.
It turns out that the manufacturer meant “leaked” when he said the seal “failed”. We wasted over a month trying to figure out what was making the seal fail before we found out it wasn’t a seal failure after all. It was another part that was failing and causing the leak, not the seal. It turned out they were testing with a slightly higher pressure than we were, which caused a plastic part to fail.
Good translation is obviously important when you are dealing with a manufacturer on the other side of the globe.
Injection Mold Tooling Problems
We have found the tooling for our plastic injection molded parts are somewhat sloppy. The parting lines are all obvious and slightly out of place, the ejector pins don’t all land on the surface they are intended to, everything is done kind of half-assed if you ask me.
Keep in mind, this was a very low budget, and with our limited funds we didn’t really have a lot of choices. The tooling works and produces parts that work, but they aren’t very pretty.
Getting code approvals in China
Working with ETL testing labs in China was just as difficult. I had to argue constantly with the Chinese engineers who worked at the ETL facility in China. Thank god for the Internet! I always won the arguments, but it took a lot of work researching and supplying documentation to the Chinese engineers.
I remember one disturbing argument; the Chinese engineer was telling me the fuse I was using for the motor was too small and needed to be bigger.
What? Bigger? How is a bigger fuse safer? It was a very surreal experience. Fuses take time to burn out. If a fuse is rated for 2.5 amps, and you run 2.6 amps through it, it may take several hours to blow. If you run 3 amps through it, it may take 30 minutes to blow. If you run 10 amps through it, it will blow in a second or two etc.
Our fuse was to protect against “locked rotor” conditions in the motor. Locked rotor is where the motor shaft is held and not allowed to rotate. Our locked rotor current would blow the fuse we were using in about 2 seconds, well before anything got hot enough to cause a fire. The fuse they were specifying would have taken several minutes to blow and danger of fire would be very real.
They finally relented and allowed us to use a fuse smaller than what they wanted but still larger than we would have liked. The one we use blows in less than 10 seconds at locked rotor conditions, but I would rather it blow in less than a second.
I’ll have more Chinese outsourcing stories in the future… some good, some bad, and some just plain funny.
More about our outsourcing experience
