Caterpillar Forest Products announces the new Prentice SC-57 center post saw to be paired with wheel feller bunchers for felling trees up to 22 in. diameter. The SC-57 also bunches medium and small stems, making it a versatile saw for thinning through final harvesting.
Designed from the ground up to meet customer expectations for durability, performance and serviceability, the saw is built to withstand heavy loads. The large box-section gathering arms are designed to support loads that can twist or bend the arms of less rigid saws. The mounting structure for the gathering arms and bunching finger further supports severe loads. Large pivot pins reduce stress and increase bushing life. The location of the lift arm pin points positions the center of gravity of the SC-57 in close to the front axle, increasing the machine’s stability, particularly when handling large stems in rough or hilly terrain.
The large surface area of the gathering arms grip and tightly hold large stems, while the “horns” of the 119 in. tall tower keep large single stems and multiple smaller stem bunches straight for better control. The positioning of the gathering arms and bunching fingers creates a large grab area optimizing control. The gathering arms and bunching fingers use a single cylinder and a link to control both the left and right sides simultaneously, improving speed and holding power.
The patented Prentice shaft and bearing design, field proven since 1999, features sealed upper and lower bearing chambers, which maximize shaft and bearing life by ensuring the top bearing is always lubricated. The shaft is tapered from 3.5 in. to 5.25 in. diameter reducing stress in the shaft during high impact.
The SC-57 carry plate is designed to minimize the risk of stress concentrations by allowing it to flex just enough to relieve some of the stress transferred through the welds.
The discharge chute allows chips and other abrasive material to be discharged from the saw housing reducing wear and enhancing disc recovery time to improve fuel efficiency. The chute is incorporated into the structure allowing thinning to both sides of the carrier.
Hoses are routed directly into the back of the head maximizing visibility. The cut-out section of the tilt link also helps with visibility. This design for hose placement and the tilt link were reviewed extensively with prototype operators to ensure the most visibility.
Hydraulic hoses are encased in heavy-duty rubber tubing, so that none are exposed to direct impact. A two-piece guard clamps around the protective tubing entering the rear of the SC-57 to provide additional protection. This guard can be removed easily to replace a hose if necessary.
The SC-57 has been designed to minimize down time for greasing, motor adjustments or maintenance. With the head tilted forward and gathering arms and bunching fingers open, all grease zerks are accessible from the ground level. There are no grease zerks located below the saw disc housing eliminating the need to grease from the bottom of the head. Two large panels allow access to the saw motor from both sides. The saw disc is easy to remove, because the housing is totally open — the skids do not need to be removed to access the disc.
The SC-57 completes the wheel feller buncher attachment line, which includes the SH-50 and SH-56 high capacity bunching saws, the SS-56 felling saw and the RH-54 high capacity shear.