A06_210512_Disc_Mulcher_Specs_2022_BLM_Final.pdf

SPECIFICATIONS

GR-MFG G-REX 60” DISC MULCHER FOR 99 – 110 HORSEPOWER

COMPACT TRACK LOADERS WITH 36 - 44 GPM HYDRAULIC OIL FLOW

Scope

The intent of this specification is to define a disc mulcher for use in wooded areas for mulching up woody materials. It must be purpose built for continuous use for mulching hardwood and softwood trees. Parts and service must be readily available throughout the state of Wyoming.

The unit must be new, unused and be prepared for service when delivered to the specified location.

Deck

The deck’s upper surfaces must be smooth, no pockets, so collection of twigs and stems are minimized and easily cleaned. It must have a fixed mounted push-bar (minimum 2.5” x 2.5” x

0.25” wall tubing) that extends above the top of the deck 26” to 28”. The push bar must have a serrated edge in front to help hold stems in place when cutting and felling. A screen (minimum of 25” thick, perforated plate with hexagon hole pattern) must be mounted to the push bar structure to help keep stems off of the deck and to protect the hydraulic motor and hoses. The push bar must be supported at the top, outer corners with arched tubes (minimum 2.5” x 2.5” x

0.25”) extending down both sides of the deck. The tubes extending down the sides of the deck offers protection to the hydraulic motor and hydraulic lines. The working surfaces

(bottom/inside) of the deck must be ASTM A-514, heat treated, wear-resistant, high-strength steel. It must be designed with a helical processing chamber and have four fixed teeth holder assemblies welded inside the deck for finer processing of materials.

Disc

The disc must be made from 1.25 inch thick, heat treated, wear-resistant, high-strength steel, machined across all surfaces and have a cut width of 60” when assembled. Machined surfaces provide for a secure/positive connection to the bearing box and for the teeth holders. The teeth holders must be bolt on design with hardened, bushing inserts. Note: No weld-on teeth holders allowed. There must be a minimum of 18 teeth on the bottom, minimum of 12 teeth on the top and a minimum of 12 teeth on the perimeter of the disc. The teeth are to be shank less and held in positon with ¾” bolts. All of the teeth are to be hardened “beaver teeth style”. The disc must have a minimum diameter bolt hole pattern of 10.5” with a minimum of twelve ¾” NF, GR8 bolts securing the disc to the bearing box.

Bearing Box

The bearing box must be heavy duty with a flange output shaft. The output shaft diameter must be a minimum of 3.94” to support the heavy loads that can be transmitted through it when mulching. The flange’s mounting surface must have a smooth machine surface and a 10.5” bolt hole circle with twelve ¾” NF threaded holes to secure the disc. The top surface for the hydraulic motor must be a SAE D. A steel stainless steel shield must be included on the bearing box lower shaft area to protect the lower shaft seal from wire and vines.

Hydraulic Motor

It must be a fixed displacement, radial piston motor for efficiency. The displacement of the hydraulic motor must be 150cc with a working pressure up to 5000 psi. The case drain system must have a low pressure relief valve to protect the hydraulic motor shaft seal from blowing if the case drain line gets blocked.

Hydraulic Lines and Connections

Must include hoses with quick couplers for pressure, return and drain lines. Hoses should be adequately secured to the deck to prevent hose damage while in operation and the correct lengths for connecting them to the tractor. Hose and fittings should have standard O-ring face seals connections for best performance.

Other Items

The total assembled weight to be minimum of 2,650 lbs. and a maximum of 2,800 lbs.

A minimum of four hours of operator training is required. It must cover safety, maintenance and operating technique.