• The equipment used for this process area hydraulic jack of retracting – extending typeset of nut bolts, and a fixture
extending approximately 10 cm.
• The winch cover plate is provided with a small hole
• The fixture piece (balled bracket) with the help of nut bolts is attached to the winch body at the hole
• The hydraulic jack and ram assembly is placed vertically below the fixture plate facing
face to face horizontally • The hydraulic jack applies force on the fixture which in turn applies the torque on the winch cover plate and tries to rotate it against the action of the winch brakes
183. l Marine Insight It is of utmost importance to ensure that the fixture is exactly perpendicular to the hydraulic jack and also parallel to the deck plating and hole in the winch cover plate Cargo Operations for Tanker I 184. Break Test Arrangement
The brake holding capacity of the winch is determined with regards to the hydraulic pressure. The winch brake is then fully applied. The hydraulic jack is manually pressurized up to the calculated pressure using the lever. Upon
applying the required pressure, hold it for sometime, say approximately 5 – 6 minutes.
Real Life Incident “There have been numerous incidents in the past when the symmetry between fixtures, jack and deck plating was not as required and due to the enormous force applied by the jack the fixture broke loose from the cover plate and went flying, causing severe head and face injuries to the crew members 185. l Marine Insight Observe the winch for any movement.
If no movement is observed, it implies that the winch brake has countered the calculated force rendered by the ram on the fixture. Thus, the brake is holding efficiently as per its marked holding capacity. Slowly depressurise the ram and jack assembly. As the pressure reduces to zero, open the nut bolts of the fixture, remove the fixture and open the brakes of the winch to normal position. Cargo Operations for Tanker I 186.