Frames & Grates

2026-11-03

The purpose of this bid invitation is to establish a contract for grates and frames to be ordered by the City of Manchester , New Hampshire as needed , during the term of the contract , in accordance with the requirements of this bid invitation and any resulting contract . Section 604 : Catch Basins , Drop Inlets and Drain Manholes 1 . All castings furnished must be of minimum class 30 - 30 , 000 lb . iron . 2 . All grates , frames , manhole covers , etc . are to be manufactured in the United States of America . 3 . Quality of finish and workmanship will be governed by AASHTO M 105 unless otherwise specified . Prefabricated metal adjustment rings for catch basins , drop inlets and manholes shall conform to AASHTO M 105 also . 4 . The word “ DRAIN ” or “ SEWER ” in 3 ” letters shall be plainly cast in the center of each cover . 5 . Type “ C ” top shall be as per NH Department of Transportation Standard Specification . 6 . Shop drawings for any frames , grates and covers shall be submitted along with bid for approval . 7 . The City reserves the right to test castings at random . 8 . Test costs will be borne by the City if castings tested meet the specifications of this proposal . 9 . Should any castings fail , the costs of the test will be borne by the Contractor . 10 . All castings from the heat of a casting that fail to meet the minimum class 30 strength requirements will immediately be returned to the vendor without penalty . 11 . Castings shall be gray iron confirming to AASHTO M 105 and AASHTO M 306 . Castings shall be proof load tested . 12 . The City reserves the right to demand immediate replacement of any component purchased from this contract that does not meet specifications . 13 . Polyethylene catch basin liners shall be used in catch basins and drop inlets and serve to protect the adjustment brick . Polyethylene liner material shall conform to the requirements of AASHTO M 294 , section 6 . 0 , but not have a wall thickness less than ¼ inch . Polyethylene liner shall consist of polyethylene sheet and downspout sections . All fabrication to be done in shop . a . Sheet Section : Shall be of sufficient size to provide minimum of 4 inches of material beyond the flange of a catch basin single frame casting . For most castings , this is approximately a 37 inch square sheet . The material shall be able to be trimmed in the field to fit conditions found . b . Downspout Section : Shall be a 12 inch tall cylinder , 20 inches in outside diameter and be extrusion fillet welded to sheet section .

New Hampshire

2026-04-28