Page 184 - CITS - Fitter Trade Practical - Volume -2

FITTER - CITS

Re-assembly

• Install a new O-ring to the speed adjusting screw on the front end cap. Replace the spacer and jam nut.
• If equipped with speed adjusting screws on the rear end cap; install new O-rings. Replace the spacers and
jam nuts.
• Install a new packing ring and O-ring and attach the piston rod plate to the front end cap with lock washers and
screws.
• Be sure the piston rod is free of nicks and burrs. Slide the front end cap onto the rod and install the E-ring.
• Assemble the new U-seal and O-ring on the piston, then mount the piston and O-ring on the piston rod and
secure with a new lock nut. See Fig 3.
• Mount ‘E’ ring, washer, piston, washer seal, washer and lock washer on the piston rod. The rubber face of the
piston should face towards the rod and bearing. (Fig 4)
• Apply a light coat of grease to the cylinder tube I.D., completely around the U-seal, (if double-acting, apply
around piston edge), the front end cap gasket, and working length of the piston rod.
• Install new cylinder gaskets on the end caps.
• Assemble the cylinder tube, rear end cap and front end cap assembly. Install the tie rods, tie rod nuts and
lock washers. Finger tighten the nuts. Then cross tighen the nuts equally and then tightened to a final torque.
(Fig 2)

Before tightening the nuts, be sure the tie rods are parallel to the long axis of the cylinder. Tie rods
must be positioned properly to obtain a good seal at both end caps.
• Re-attach accessory items and aiir lines to the cylinder.

• Re-install the cylinder in the machine and connect air and electrical lines.
• Verify proper operation of the cylinder.
Testing the cylinder
• Apply air to the inlet port on the front end cap. Use a brush with a soap and water solution to check for leaks.
Do not submerge the cylinder.
• With air applied to the speed fitting and the piston rod fully extended, open the air passage in the speed fitting
and observe that the piston moves to the rear cap. Check for leakage at the front cap adjustment screw; at the
front cap ppiston rod seal; at the rear cap adjustment screw and adjacent ports (if equipped); from the piping
between the speed fitting and the front end cap; from both ends of the cylinder at the cap gaskets; and from
the speed fitting exhaust port. Repair any leaks and recheck.
Construct a circuit for the direction & speed control of a

small bore single acting (s/a) pneumatic cylinder

Objectives: At the end of this exercise you shall be able to
• select the components, to operate Single Acting Cylinder using 3/2 way valve
• draw circuit diagram on paper
• assemble circuit on the trainer board
• check function of the circuit.
Requirements

Tool / Instrument / Equipment / Machines Material / Component

• Trainer board - 1 No. • P U Tube - as reqd.
• Pneumatic source - 1 No. • Paper - as reqd.
• Pencil - as reqd.
• Single Acting Cylinder - 1 No.
• 3/2 way valve - 1 No.
• FRL - 1 No.

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CITS : C G & M - Fitter - Exercise 89