TECH 343 Servo and Nonservo Hydraulics

Lab #7: Rapid Advance & Feed Circuit

Equipment

1. Vickers hydraulic training bench

2. Cylinder, horizontal

3. Directional valve

4. Flow control valve

5. Decel valve

6. PC w/Labview program

Objectives

1. To design and operate a rapid advance and feed circuit.

2. To design and operate a rapid advance and variable feed circuit.

3. To determine the effects of speed control on the rapid advance and feed circuit.

Procedure

1. Using all the items except the flow control valve design and construct a rapid advance, feed, and rapid return circuit.

2. Operate the system and record the pressure and velocity for extension, feed, and retraction.

3. Add the flow control valve to vary the feed rate.

4. Repeat step 2 for at least three different settings for the flow control valve.

5. Tabulate the data.

Questions

1. Was it possible to control the feed rate only without effecting the rapid advance?

2. Is it possible to obtain rapid advance equal to the retraction speed and still have variable feed?

3. Can the same amount of force be exerted by the cylinder during the feed stroke at different velocities?