Often we hear about "value engineering","value assessment" etc., as applied in the industry environment. Can someone clarify on what is meant by these terms and how these are useful in the industry?
Well, there is a balance between being overdesigned and underdesigned or properly designed in all things.
Often extra safety it built into a thing by overdesign, say in an elevator cable that will only ever see 2000 pounds, for safety you build to 4000 pounds and you have a safety factor, as well as an extra cost. Obviously a cable made for 2001 pounds would have an inadequate safety factor and would fail at 2002 pounds(humor me).
So value engineering usually means a design that takes into account all aspects of the material and it's uses and safety factor, and makes it meet those requirements. This will be the lowest acceptable cost.
You can make it three times as strong at extra costs and you will have wasted money as that strength will never be needed.
Endurance of an engine. Ever wonder why a Cummins diesel will run for millions of miles, yet your car gas engine reaches end of life at 200,000 miles or so?
The diesel has pre-pressurised oil galleries, so when you start the oil pressurises the bearings and jornals for a few seconds and then it is is started. That costs more $$.
A car engine starts with zero lubrication and for the first few turns it is metal on metal, and then the oli pressure rises. Why is that? It is cheaper and it also ensures that cars do not last for a million miles. Keep a car running 24/7 and it will go a million miles...see taxis.
So another aspect is value engineering is planned obsolescence. In theory if you can very good designers they can make a car that runs for the 100,000 mile warranty and fails at 101,000 miles. They cannot quite do this, but they would love to.
Value engineering means reducing the gap between what features a product has, versus what is actually used, and improving those features that are used, as permitted by the removal of the unused features and/or price point. In other words, give me what I want, not what I don't, and make it work better for the same or less money.
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You can have it good, fast or cheap. Pick two.
All very good responses so far but none have touched the fact that value enginering is not only what you make (and the features it includes) but also how its made. For example, removal of any parts that could be made incorrectly i.e. if a part can be fitted more than 1 way then the chances are it will be; and if 1 of those ways doesn't work then the design is wrong. So make parts that will either obviously only fit 1 way round or it doesn't matter which way round its fitted. For this reason also, the number of different types of screws should be kept to a minimum i.e. if 1 type of scew (length, width etc) will fix everything then use only 1 type of screw). CAr manufacturers often use common parts across the range of cars produced. Even across companies (i.e. Renault & Citroen use the same doors on some models). Getting back to screws.. why use screws at all if you can just press it altogether? Look at how PC cases and pretty much defunct CRT monitor cases are put together. Hardly a screw insight!
Yes, saving assembly time and reducing parts count is a valid way to value engineering.
As for snap together, there is some of that in cars now, and computer cases and printers etc.
Common parts throughout the industry even to the point of making laws that tell car makers to use the same standard nuts for the same task. There is no valid reason why this cannot be done.
The maidn reason it has not been done is car makers feed off their parts chain. Each part you buy from a car maker costs 4-5 times as much as a comparable part from a competitive market.
Some parts are made by others to fit brakes etc, and the car makers start "genuine ford parts" marketing campaigns to make you think you and you family will die a horrible death if you fail to buy those Ford parts.
Moving slightly off the track here but I tend to agree with buying geniune parts. I have already fallen foul of what might happen if genuine parts are not used. In this instance it was clutch bolts that were not up to the correct standard (although they were marked to be so) and 4 out of 6 sheared off when tightened to the original manufacturer's torque figures. It was only a clutch assembly in this instance and the failure occurred during re-asembly. However, I could easily have been less fortunate had such a failure occurred, say to the braking system under stress (like when you actually need to use the brakes) and I may not be here to discuss this issue now.
Here the case is slightly different in that the supply of these parts was not from a value engineered item from the original manufacturer but from a low cost alternative. However, the issue is not so far away from the original topic...it simply means that value engineering, is about finding 'optimum' costs, not just cheaper costs and not by compromising reliability or safety by using sub-standard parts or materials. At the end of the day the product has to fulfil the performance requirements under all expected conditions. If materials are replaced (with presumably cheaper ones) or for whatever reason, not just cost saving, then the product design has to be re-analysed to ensure all original criteria are still met.
Yes, Walmart buys cheap parts. You can buy parts from the parts shops as they have to make sure their parts meet OEM needs since garages buy from them and word would soon spread if the parts were bad.
NAPA is an association that deals with this stuff.
All are good examples of Value Engineering. Another clarification. Value Engineering is usually conducted in a meeting like forum with all the major players participating (like a "Brainstroming Session"). As an example, I recently was involved with one that dealt with the design of a new office building. Attendees included the project manager, project engineers, architects, designers and most importantly the customer. One particular value engineering topic dealt with the issue of getting electrical power to the building. Immediately we thought, we must get it from the power source (nearest sub-station) of course. Another words, we need to run a new line to the nearest sub-station. Further dialogue raised the question "Do we go overhead, above ground, or do we go underground?". This lead us into discussing our routing options. We discussed how other buildings near our building site routed their power. Then v'iola an interesting question came to the table. "Is there an existing conduit already going to a nearby building that is of sufficient size, that we could run our power line in it?" Research identified that one of the nearby buildings had laid additional conduits which we were able to negociate and utilize. This saved bucco dinero. Thus another example of how value engineering can identify money saving options.
Value Engineering
Re: Value Engineering
