Tesla engineer: 40% of parts on Model 3 conveyor require rework



A few weeks ago, CNBC's American business news channel, citing “numerous” anonymous sources from “current and former Tesla employees,” spoke about problems at Gigafactory 1 in Nevada. They said that assembly on the conveyor is partially carried out by the old-fashioned methods - manually, practically without the use of robots. For example, manually assemble the battery modules.

Representatives of Tesla explained in a commentary to CNBC that manual assembly is not a revelation, but is planned from the very beginning: “Until we reach full production, by definition some elements of the production process will occur using manual assembly. This is what Elon Musk and technical director Jeffrey Strobel spoke in detail at a teleconference following the results of the third quarter, and this does not affect the quality or safety of the batteries we manufacture. ”

But workers argued that because of manual assembly without proper quality control, unsafe battery modules were leaving the assembly line, where "the elements are in contact with each other."

Tesla shares fell, although the company again denied: “The suggestion that Tesla will ever release a car with a dangerous battery is completely inaccurate, contrary to all evidence and divorced from reality. Each battery in a Tesla car has thousands of cells, the vast majority of which have the same voltage potential as neighboring cells. Hypothetically, even if two cells with the same voltage potential are in contact, this will not lead to anything dangerous - it’s like the contact of two neutral pieces of metal. ”

Tesla representatives noted that despite the absence of danger, all cell positions of Model 3 battery modules are measured twice in production to verify process control and the quality of outgoing parts. If at some point in the production process cells with different potentials come into contact, then they cannot be interconnected. Three different tests take place on the conveyor to verify that the correct number of cells are electrically connected in the Model 3 battery.
Tesla assured the public of the complete safety of the assembly process and the absolute impossibility of releasing defective models for sale. But now, CNBC has released another report on the same topic, but from a different angle.

Tesla employees are again talking about quality control. Only now the main thesis is not in the release of dangerous products for sale, but in a large percentage of rejection of parts. So, one anonymous engineer from the Tesla factory in Fremont says that 40% of parts produced or received at the factory require rework. According to him, the need for additional verification of parts coming off the assembly line is one of the reasons for the delay with the release of Model 3.
Another anonymous worker at the same factory said that the reject rate is so high that it will be very difficult to meet the planned deadlines and reach the required production volumes . Failure to comply with release plans, in turn, negatively impacts employee morale, he said.

CNBC quotes two employee recruitment announcements ( 1 , 2 ) for which unusual job responsibilities are indicated: the first has the obligation to “analyze new failure modes” for parts that are off the assembly line, and the processing head is hired for daily “large volume” operations repair and restoration of electric vehicles. "

Tesla responded to these allegations. According to a company spokesperson, CNBC has confused the concepts of factory overhaul or remanufacturing and rework. “Re-production is a process that literally every carmaker in the world does,” said a Tesla spokesman. - CNBC grabbed a couple of lines from two job descriptions posted on the Internet and made rude assumptions about the inaccurate job functions of these employees. Our re-production team is very small, accounting for only 0.1% (40 people) of nearly 40,000 employees. Any “expert” who claims something unusual in our process of re-production or insufficient quality of cars that go off the assembly line either confuses something very much or is completely mistaken. In fact, like other automakers, Tesla reassembles the parts because less material and energy is wasted in this way than when creating a new part from scratch. “It’s a good thing that ultimately benefits the environment and, if the part is correctly made, it is equally good for the client.”

According to the original plan, Tesla was going to produce 20,000 Model 3 cars monthly since December 2017. Then the deadlines were postponed. It is now said that by the end of this month the conveyor will be released for 2500 cars per week, and by the end of June - for 5000 cars per week.