Suggested Specifications for Construction Castings

General:  This specification is applicable for gray and ductile iron castings.  All castings shall be manufactured in the United States of America.  All manufacturers shall be approved suppliers and be able to demonstrate that there is an acceptable quality control program at the producing foundry, prior to supplying castings.
 
Materials:  Gray iron castings shall be manufactured from iron conforming to ASTM A48, Class 35B, as noted in section 3.1 of AASHTO M306.  Ductile iron castings shall conform to ASTM A536.  The iron material used in products provided shall have a minimum recycled material content of 75%.  The recycled materials shall consist of post-consumer material.
 
Manufacture:  Castings shall be of uniform quality, free from sand holes, gas holes, shrinkage, cracks and other surface defects.  Castings shall be ground smooth and well cleaned by shot blasting.  For traffic service castings, bearing surfaces between manhole rings and covers or grates and frames shall be cast or machined with such precision to prevent rocking.  As-cast dimensions may vary within accepted foundry tolerances as outlined in the Iron Castings Handbook published by the American Foundry Society, Inc.  Nominally, casting dimensional tolerances shall be +/- 1/16” per foot.  All published casting weights are average and approximate values and shall vary +/- 5%.  Castings shall be furnished painted or unpainted as specified by the purchaser.
 
Proof Load Testing: Traffic service castings shall have a first article proof load test conducted and the results of that proof load shall be made available to the purchaser upon request.  The proof load shall be conducted in accordance with the method and procedure that is outlined in AASHTO M306, Section 7.0, Proof Load Testing.  The casting shall be tested on a suitable and calibrated load testing machine and the casting shall hold a 40,000 pound proof load for one minute without experiencing any cracks or detrimental permanent deformation.
 
Inspection:  Inspections shall be in accordance with 9.1.1 (refer to above-Proof Load Testing) or 9.1.2 of AASHTO M306.  Results of these tests shall be furnished to the purchaser upon request.  The heat or production date and product numbers, as cast on the casting shall be the basis of trace-ability and recording of the tests.
 
Certification:  A foundry certification shall be furnished to the purchaser stating that samples representing each lot have been tested, inspected, and are in accordance with this specification.
 
Marking: Each casting shall be identifiable and show, at a minimum, the following: name of the producing foundry, country of manufacture (such as “Made in USA”), ASTM material designation, recycle symbol, individual part number, cast or heat date.  Castings shall include all lettering as shown on the specification drawings.
 
Sampling:  Random checks on the castings may be conducted by the purchaser.  These random checks shall be conducted in accordance with AASHTO M306, Section 6.0 guidelines.
 
Records:  Test results for each lot of castings shall be maintained by the foundry for a minimum of seven years and shall be made available to the purchaser upon request.