Coupling Operations

1
Objective
Coupling Operations
At the completion of this lesson you, the student
will be able to demonstrate the skills and
knowledge required to couple and uncouple a truck
tractor to/ from a semitrailer without error,
damage to equipment or injury to personnel.
88M12C02/1
2
Coupling operations
Safety Briefing
Engage parking brake and chock wheels Make a 360
degree walk-around inspection Use three points of
contact when mounting and dismounting Wear
hearing protection when equipment is
running Clear personnel before starting
engine Use of ground guides and hand and arm
signals Emphasis on air pressure gauge Seat belts
must be worn at all times when vehicle is being
operated Remove ice from top of semitrailer
(winter months)
88M12C02/2
3
Coupling operations
Environmental Considerations
Watch for any equipment fluid leaks Avoid damage
to vegetation or contamination to soil Keep
idling time to a minimum Do not discharge water,
oil, or antifreeze onto the ground, into street,
or storm drain system.
88M12C02/3
4
Coupling operations
Coupling

• Place chock blocks
• Check equipment
• Fifth wheel cracked, damaged, or missing parts.
• Fifth wheel mounting bolts for tightness.
• All moving parts on top of fifth wheel for
• proper operation.
• Lock guard for proper operation. Make sure both
• primary lock release pull ring and secondary
• lock release handle are pulled out and guard
  lock
• guard is open to accept the trailer kingpin.

88M12C02/4
5
Coupling operations
Coupling (continued)

• Fifth wheel ramps are down level with or
  slightly
• below the angle of the pickup ramps
• Adjust trailer height so the fifth wheel picks
  up the
• trailer.
• Be sure fifth wheel air slide control is set to
  the lock
• position.
• Align tractor.
• Slowly back tractor.
• Ensure the semitrailer and fifth wheel ramp make
  contact.

88M12C02/5
6
Coupling operations
Coupling (continued)

• Connect air hoses.
• Push in tractor and trailer air supply knobs and
  set trailer
• brake hand control lever.
• Back up slowly until fifth wheel locks. With
  trailer brake
• hand control lever set, pull forward to ensure
  a secure
• coupling.
• Return trailer brake hand control lever to Up
  position and
• set (pull out) tractor and trailer brakes.

88M12C02/6
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Coupling operations
Coupling (continued)

• Verify lock release handles are in.
• Check to ensure kings pins are in the locks
• Ensure kingpin is not hooked over the front of
  the fifth
• wheel.
• Connect electrical cable and check lights,
  brakes, and
• all tires.
• Lift and secure the semitrailer landing gear and
  stow
• the crank handle. Stow chock blocks.
• Make sure the air supply is adequate before you
  start
• moving vehicles.

88M12C02/7
8
Coupling operations
Uncoupling

• Shift range selector to neutral (N).
• Pull out the trailer air supply valve.
• Place chock blocks
• When parking uphill, place chock behind the rear
• wheels on both sides of the semitrailer.
• When parking downhill, place chocks in front of
• the rear wheels on both sides of the
  semitrailer.
• When parking on level ground, place chock
• firmly in front of a wheel on one of the axles
• and firmly behind one wheel on the other side.

88M12C02/8
9
Coupling operations
Uncoupling continued

• Remove the float pads from brackets and place
  them
• under the landing support legs.
• Lower landing gear.
• Disconnect and secure air hoses and electrical
  cable.
• Unlock fifth wheel.
• Slowly pull tractor forward.
• Ensure semitrailer is supported by landing gear
• Make sure the kingpin will clear the rear frame
  cross-
• member.
• Pull forward totally clear of the semitrailer.

88M12C02/9
10
Summary
Key Points

• Safety Briefing
• Environmental Briefing
• Coupling Operations
• Uncoupling Operations

88M12C02/10