1976-11-22 Regular Meeting - Laserfiche WebLink

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Bid specifications co~nued Page 2 The screed shall be constructed of a basic frame work designed to allow the screed plate to be bolted to its bottom surface. The screed plate shall be 3/16 of an inch thick and made of a material having a Brinnel hardness range from 360 to 400. The • screed plate shall have studs affixed in a symmetrical design which allows the leading and trailing edges to be reversed. The studs shall be fastened to the screed plate in such a manner that they do not cause deflection due to manufacturing processes. The screed plate shall not have had holes drilled through it in order to fasten the studs to its surface. The paver shall be equipped with a hydralically-operated screed hoist mechanism powered from the cental hydralic systen which affords eight tons of lifting force. This system shall be operated by a high quality hydralic cylinder. The lever arm of the hoist shall pivot away from the hopper back affording clearance of the hopper back and lift chain. The paver shall be equipped. with hydraulically-operated hook-up arms that insert into the truck wheels. These arms shall have rim rollers that insert into the truck wheels and side rollers that run on the side of the tires. These rollers shall ve mounted on bronze bushings. The hitch arms shall be manufactured in such a nanner that the arm can be disassembled for the replacement of these bushings as required. The hitch arms shall be operated from a central hydraulic pump at the left screed operator's position. It is the intention of this specification to purchase a paving machine that will attach to any truck without the paving operator having to walk in the newly-laid material. The hitch arm arrangement shall be operated remotely by a hydraulic pump. All hydraulic functions of this paver shall be either gravity-or spring-return to • their opened position. The paver shall be equipped with a hydraulic hand pump of a three-piston design that allows each of the hydraulic functions (screed hoist mechanism, shut-off gate, and hitch arms) to work independently of each other. The pump shall be of such a design that a normal mechanic can rebuild the unit in the field without the use of special tools. The suction and discharge check valves shall be manufactured in such a fashion that they are replaceable. They shall be cartridge-mounted in order that they can be removed and cleaned in the event that this is required. The hand pump shall have individual shut-off and release valves for each of the three pistons of the hand pump. These shut-off valves shall be equipped with their own handles permanently attached in such fashion that they cannot be lost during the paving cycle. This pump shall be of'a high quality with premium hydraulic seals through- out. The pump shall be mounted on the left side of the paver in such a position that it affords a cover being palced in a hinged method over the pump, thereby alleviating the posibility of asphalt or other foreign objects being spilled upon it. The intention of this specification is to get a high quality hand pump that is field repairable by those people who would normally be associated with the use of this machine. The hydraulic hand pump must be manufactured by the paver manu- facutureer. ELECTRIC - POWERED HYDRAULIC SYSTEM ( with battery )_ Includes 3-position selector valve plus position locking valves for hitch arm, shut- off gate, and screed hoist. The hand pump remains on the paver as a second system. • The complete unit bolts on to the rear wall of the hopper. The components are enclosed in locking control boxes. A removable center hopper section is included.