Hydraulic Circuit
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| Illustration 1 | g03422885 |
Hydraulic schematic for CTV30 Clam Shell Grapple (1) Rotation motor (2) Crossover relief valve (3) Check valve (4) Orifice (5) Orifice (6) Check valve (7) Auxiliary control valve (8) Pump (9) Hydraulic oil tank (10) Pump (11) Auxiliary control valve (12) Swivel (13) Hydraulic cylinders | |
The hydraulic system for the Clam Shell Grapple is divided into two separate circuits. One circuit is used to rotate the work tool and the other circuit is used to operate the shell assemblies.
- The hydraulic circuit for the operation of the shell assemblies.
The main components of the clam shell grapple circuit consist of the swivel (12) and cylinders (13) .
- The hydraulic circuit for the rotation of the work tool.
The main components of the rotate circuit consist of the following components: rotation motor (1), crossover relief valve (2), check valve (3), orifice (4), orifice (5) and check valve (6) .
Shell Circuit
Swivel (12) is the center of the rotator assembly. The swivel provides the necessary transfer of hydraulic oil to the hydraulic cylinders in the Clam Shell Grapple. This transfer of oil allows the Clam Shell Grapple to rotate 360 degrees without damaging the hoses to the cylinders.
Double acting cylinders (13) provide the necessary force in order to operate the shells of the work tool effectively. The hydraulic circuit for the cylinders is independent from the circuit for rotation.
Close the Shell
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| Illustration 2 | g03423145 |
Clam shell hydraulic circuit (9) Hydraulic oil tank (10) Pump (11) Auxiliary control valve (12) Swivel (13) Hydraulic cylinders | |
Illustration 2 demonstrates the operation of the work tool when the shells are closing.
When auxiliary control valve (11) is shifted left, oil flows from the host machine pump (10) through swivel (12). The oil then flows to the head end of cylinders (13). The oil pressure that is felt at the piston in the cylinder causes the cylinder to extend. This action closes the shells.
Oil from the rod end of the cylinders returns to hydraulic oil tank (9) through swivel (12) and auxiliary control valve (11) .
Open the Shell
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| Illustration 3 | g03423163 |
Clam shell hydraulic circuit (9) Hydraulic oil tank (10) Pump (11) Auxiliary control valve (12) Swivel (13) Hydraulic cylinders | |
Illustration 3 demonstrates the operation of the work tool when the shells are opening.
When auxiliary control valve (11) is shifted right, oil flows from the host machine pump (10) through swivel (12). The oil then flows to the rod end of cylinders (13). The oil pressure that is felt at the piston in the cylinder causes the cylinder to retract. This action opens the shells.
Oil from the head end of the cylinders returns to hydraulic oil tank (9) through swivel (12) and auxiliary control valve (11) .
Rotate Circuit for Clockwise Rotation
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| Illustration 4 | g03423170 |
(1) Rotation motor (2) Crossover relief valve (3) Check valve (4) Orifice (5) Orifice (6) Check valve (7) Auxiliary control valve (8) Pump (9) Hydraulic oil tank (10) Pump (11) Auxiliary control valve (12) Swivel (13) Hydraulic cylinders | |
When a rotate function is desired, auxiliary control valve (7) shifts. The direction auxiliary control valve (7) shifts will determine the direction that rotation motor (1) turns by diverting supply oil to either side of the rotation motor.
Hydraulic oil is supplied by host machine pump (8) and flows through auxiliary control valve (7). Hydraulic oil flow for the rotate circuit is restricted by check valve (3) with orifice (4), and orifice (5) with check valve (6). Return oil is sent back to hydraulic oil tank (9) .
Crossover relief valve (2) prevent cavitation in the grapple rotate motor. The relief valve will also prevent a shock load when the grapple rotate motor stops.