A company received an order from a user, and the diameter was 69.5, but it was scrapped. The customer said that the diameter was reduced by half. If Party A is in a hurry for this kind of workpiece, once it is reworked, it is likely to affect the processing progress of Party A's company, and if it goes wrong, it will pay millions of dollars in violations.
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After receiving this news, other people in the company immediately began to calculate, and there were various results. The scene at that time was really ants on the hot pot. Fortunately, one of the colleagues saw it and said that the marking method was wrong. Generally, symmetrical workpieces should be marked with taper, so this drawing is not very standardized. 1 Calculate the angle.
Let's first take a look at the difference and calculation method of these two labels
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From Baidu
After reading this post, I remembered that when I first entered the factory, the master always asked me to mark the angle when drawing the paper, because most of the time I was used to marking the length and two diameters and it was over. Every time this happened, the master taught me not to mark the angle. When I saw this post today, I suddenly felt that the master was really well-intentioned, but if the drawing was marked with an angle, there would be no such big loss.
In fact, workers in many factories just do their work, and there is nothing wrong with the labeling in this picture. It’s just that the workers don’t have a thorough understanding of the uncommon symbols. In the absence of angles, the workers follow the common understanding to do the work. Even I thought the drawing was from the SIN value at first glance, but it turned out to be the TAN value, so I must not be careless when looking at the picture! careless! careless!
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In addition, the company's design is not rigorous, and the drawing review personnel for machining are also not rigorous. If this kind of work requires turning taper, the standard size and angle should be detailed. Those factories in the workshop do not have computers available, and the processing personnel in their workshop sometimes don't bother to calculate the size of the chamfer by themselves.
I remember that a friend once did a lot of work, converting foreign blueprints into something everyone can understand, and the numbers don’t matter, just × 25.4. But there is a roughness, because the drawing is dirty and not very clear, there is a standard of 125, they defaulted to 12.5, the result was done according to 12.5, and the customer came to pay the full fee, 125 corresponds to the national standard 3.2.
This kind of heavy work is a trivial matter. If Party A seriously delays the delivery date and has to pay a huge amount of illegal money, it may lose customers and easily form a bad evaluation in the circle. It can be said that it is not worth the loss.
So those who work in our mechanical industry should really be cautious at ordinary times! cautious! Be more cautious! Losing money is a small matter because of mistakes made in design and drawing, and being sentenced to prison is really not worth the gain. Don’t think it’s just talk!
As a designer, you must be rigorous: try to strictly follow the drawing standards, think more about it for the workshop processing personnel, try to be clear and concise, and send more 3D drawings to Party B, so as to avoid the probability of errors as much as possible.
As a related person: you must not be sloppy when looking at the pictures, and you must ask when you are not sure, and you must not be too troublesome. Under the premise of not being able to figure out the markings on the drawings, blind processing is not allowed, and batch scrapping will occur. Don’t start work if you don’t confirm the good specifications, don’t be lazy even if it’s troublesome in the early stage, even if you start work, you must have samples, and don’t finish a batch of work confidently without samples.
