Grey Iron castings shall conform to the requirements of AASHTO M 105 Class 35 B or ASTM A 48 Class 35 B, unless otherwise specified.

Castings shall be manufactured true to pattern and component parts shall fit together in a satisfactory manner. They shall be smooth and well cleaned by shotblasting. Circular manhole rings, covers and grates shall be furnished with machined horizontal bearing surfaces unless otherwise specified. All square and rectangular units shall be furnished with an as-cast bearing surface.

As cast dimensions may vary by plus or minus 1/16 inch per foot in critical areas relating to fit, load bearing capacity and drainage openings. Non-critical dimensions may be modified slightly to facilitate proper casting techniques, without notice. Notwithstanding these tolerances, all rings, covers, frames, grates, and curb hoods of the same nominal size are interchangeable.

Casting weights are accurate, and shall be within plus or minus 5% of the specified weight.

Castings are supplied unpainted, unless specified. For special paint applications, contact our customer service department.

U.S. Foundry steel frame, cover and grate products are manufactured with ASTM A36 or  A-572 structural steel. Riveted grates are manufactured with ASTM A36 structural steel and/or A569 commercial quality sheet and strip.

Our steel products are manufactured by highly skilled craftsmen using state of the art equipment and AWS welding procedures.

The tolerance for steel riveted grates is plus or minus 3/16 inch. When the width of a riveted grate is over 5 feet-0 inches, the width tolerance is plus or minus 1/4 inch. All other steel fabricated products are to industry standards of plus or minus 1/16 inch, whichever is more stringent.

Steel product weights are approximate and shall be within plus or minus 5% of the catalog published weight.

Steel frames, cover and grates can be finished to meet your special requirement. Our standard finish is one coat of water based black paint. The most common optional finish is hot-dipped galvanized. (Note: unless otherwise specified, galvanized finishes are standard for airport products and direct traffic & parking lot access hatches.)