Additional Counterweight For 236 And 246 Skid Steer Loaders Caterpillar

Additional Counterweight For 236 And 246 Skid Steer Loaders

Usage:

SKID STEER LOADERS236 (4YZ),
246 (5SZ) SKID STEER LOADERS

Problem:

Adding counterweight for specific machine configurations and operating conditions.

DISCUSSION:

Understanding customer requirements, available machine configurations and using proper machine operating techniques for the CAT SSL product lineup are critically important as we strive to satisfy the needs of the machine users. Caterpillar offers a wide variety of Worktools to accommodate these needs. Selection and application of the Worktools can significantly affect the machine operation and dynamics. Rated Operating Capacity (ROC), calculated as 1/2 of the static tipping load of a SSL, is a common parameter when evaluating which machine configuration will provide optimal machine performance for a specific application. An example table highlighting the effects is shown:

For a Caterpillar 246 SKid Steer Loader:

As shown, Worktool selection has considerable impact on the ROC of the machine. The Cat Bucket & Fork specification book AEHQ5360 recommends the 66" versions of the buckets as providing the "optimal system performance" for the 236 & 246. The 60'/72' versions are available to give customers flexibility, working in different conditions with different materials. Knowing the customers' applications and properly matching Cat SSL's/Worktools is critical to meeting customers' expectations.

Solution:

In an effort to respond to field requests for enhanced machine performance; for customers that understand their machine application, configuration, and rated operating capacity; the SSL Product Development Team is recommending an optional attachment counterweight group for the 236 & 246 skid steer loaders. This counterweight package will provide an additional 100 lbs of Rated Operating Capacity (ROC) improving the machine's dynamic performance when using heavier Worktools or when loading high density material with wider buckets.

Following are parameters for the counterweight (CTW) package:

1. Performance Requirements:

- the added weight to the rear of the machine should not exceed 75 lbs(34kg) per side or 150 lbs(68kg) total.

2. Optimal Location (low and to the rear of the machine):

- the CTW should be attached to the base of the rear tower

- the CTW should NOT extend above the height of the bumper

- the CTW should NOT affect the rear departure angle of the machine

- the CTW should NOT affect the rear turning radius by extending beyond the outside of the wheel arrangement and the bumper

3. Counterbalance (CB)Weight - To maintain acceptable front to rear machine axle weight distribution WHEN NO WORK TOOL IS ATTACHED, weight should be added at the for/aft axis of the front axle of the machine, at a ratio of 0.58:1 to the CTW added to the rear tower.

Example: 150 lbs added to the rear tower of the machine would require 87 lbs to be added at the for/aft axis of the front axle.

- the CBweight must be secured to the floor of the lower frame

- the CBweight must be equally distributed left-to-right

- the CBweight must be along the for/aft axis of the front axle

- the CBweight must NOT interfere with the electrical harnesses, hydraulic lines, or the function of the governor/throttle controls

- it is recommended, but not required, that two CBweights, fitting an envelope of: 80mm high x 200mm wide x 175mm, be located in the front corners of the lower frame, flush with the side and front plates.

FURTHER INFORMATION:

For dealers requiring additional details on counterweight design and installation, a fabricated counterweight can be made from the [attached] field installation drawings, and consultation from the SSL Product Customer Support Team in Sanford. This counterweight meets all of the criteria specified above. An integrated counterweight package with the above design features will be offered as an optional factory attachment for Cat SSL's early next year.

The left and right counterweight are mirror parts. See Illustration 1 for the left rear counterweight. See Illustration 2 for the right rear counterweight. See Table 1 for the dimensions. Fabricate two front counterweights using Illustration 3 and Table 2. Install the counterweights using Illustation 4 and 5.

SUMMARY:

This counterweight package is designed to increase the operating capacity of a 236 or 246 machine for applications that use wider buckets, heavier work tools, and/or handle relatively dense material. Adding this counterweight can compromise machine performance in some operating conditions. The power-to-weight ratio is reduced and increased tire wear may be experienced. As stated above, understanding customer requirements and machine configurations for the CAT SSL product family is key to maximizing machine performance.

Table 1. Illustration 1.