sitated a slightly diff erent acceptance criterion than the prior example— ASTM A609 method A level 2. T e 7,000-lb. casting was inspected and found to be acceptable. T e costs were covered by the customer. Following the casting damage


due to fork truck driver error, the customer requested that the met- alcasting supplier sign off on the casting being acceptable for use. A letter was drafted with generic (not part-specific) considerations. The letter placed all responsibilities to perform additional inspections and determinations for use in the customer’s hands.


Problem 4: Confl icting Inspectors


On a very large steel casting (11,300 lbs.), the casting supplier and customer spent considerable time on machine stock, draft and other cast- ability issues prior to pattern construc- tion. However, a defect on a machined surface was reported on half the castings in the fi eld. T e customer was working from two construction sites; one inspector rejected the castings, while another site inspector reported no problems.


Repercussions In this instance, the machine shop


performed a clean-up cut on what was designed to be a cast surface. T is resulted in little to no material being removed from a 20 x 80-in. area. Without participation from the casting supplier, the customer was able to submit the castings to ultrasonic inspection and use the parts after they passed the test.


Problem 5: Drawings for Sub-Structures


A customer submitted drawings not of individual castings but of


@


ONLINE RESOURCE


For succesful buying strategies, go to www.metalcastingdesign.com.


Jan/Feb 2012 | METAL CASTING DESIGN & PURCHASING | 43


When the proper specifi cations are in place, casting imperfections can sometimes be ground away prior to the component leaving the steel casting facility.


small sections of an entire structure.


Repercussions Each of the parts had to be dis- sected and recreated by the purchaser’s engineers and the casting supplier. T e new plans failed to show ma- chine stock, draft or tolerances. T e metalcaster’s pattern engineer and the


customer then spent numerous hours discussing the dimensional alterations necessary to make the parts cast- able. T ese eff orts still failed to catch unforeseen problems. 


This article was adapted from a presentation given at the 2011 Steel Founders’ Society of America National Technical and Operating Conference.


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64