When all factors are put together and the calculation correctly done, even a very tiny increase in yield will result in important cost savings. Wave solder defects are very, very expensive. Anything that will reduce the number of defects will show a cost savings. The problem is not only with "poor quality" wave soldering, but also with wave solder results that are generally considered "satisfactory" and even "excellent." Since a defect rate of 0.5% is considered good, the overall cost of "acceptable" wave soldering in the electronics industry is nothing short of astronomical. A major problem is that normal accounting procedures usually put field failures into a separate budget from that of the factory, and so the true costs are never articulated. Your own data will provide compelling evidence that new steps are not only necessary but also extremely cost effective even when only a part of the overall figures are considered. Improved Process = Fast Results In company after company, the prevailing defect rate now considered "acceptable" causes annual costs many, many times more than the implementation of sound procedures. Even worse, it can result in a field failure rate that can only damage the reputation of the product and eventually confidence in the assembly plant.

This is so completely unacceptable in this era of contract manufacturing, so damaging to the competitive posture and profitability of the assembly facility, it astonishes that the vast

Inspection and Rework are Futile

Regarding inspection, at normal levels of solder joint inspection the inspector is at best sampling the quality of the joints on each board and, from the external appearance of the joints, assessing the chances that a satisfactory result has been achieved on all of them. This assessment of each and every joint is obviously ridiculous. The responsibility for high quality PCBs lies with the process, not with the inspector. Likewise for rework. There is general agreement that rework of defects results in joints with shorter lives than those successfully made in the wave solder environment.

Conclusion

The real solution is to ensure that the wave solder optimizer process produces the highest portion of joints possible that are correctly soldered from the start. Direct data on board-wave interaction - parallelism, dwell time and immersion depth - are essential for the achievement of real repeatability and true optimization. Fortunately, this is now easily attainable.

Wave solder defects are the most expensive process deficiencies in the electronics packaging industry. When the cost of wave soldering is considered, the evaluation must stretch further than the actual wave soldering itself. The cost of assuring reliable PCBs - the cost of inspection, touches up and rework - and, of course, the ultimate expenditure of making right field failures, must be included in the final figure. More than any other cost element, the cost of wave solder defects is misunderstood.

This site www.swpc.co.il provides full study of lead-free wave soldering. It facilitates manufacturers to save their money by upgrading their present wave soldering machines.

Article Source: http://www.therealarticles.com

Please Rate The Above Article From The Hardware Category

5 out of 54 out of 53 out of 52 out of 51 out of 5 

Not yet Rated

Click the XML Icon Above to Receive Hardware Articles Via RSS!