 | |
| Illustration 1 | g03425573 |
(1) Port - "G" (grapple close) (2) Port - "GO" (grapple open) (3) Hydraulic cylinder (4) Piston (5) Rod | |
 | |
| Illustration 2 | g03425596 |
(6) Head end (7) Rod end | |
Hydraulic cylinder (3) is a double acting cylinder. The Grapple uses two hydraulic cylinders in order to operate the shells.
When oil is supplied through port (1) to head end (6) of the cylinder, the oil forces piston (4) to move to the right. Since piston (4) and rod (5) are connected, the rod is forced out of the cylinder housing. This action closes the shells of the work tool. When oil is supplied through port (2) to rod end (7) of the cylinder, the oil forces piston (4) to move to the left. As a result, the rod retracts into the cylinder housing. This action causes the shells of the work tool to open.
The maximum operating pressure for the cylinder is 35000 kPa (5100 psi).