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Motor Hydraulic Bulk Grab

2015-03-05 15:31
1. Rules of operating
(1) This grab can be attached on the ship’s deck-crane’s hook for coal. These grabs are not able to attached on the port-crane and other similar mechanism.
(2) Grab electric control system should protect grab form over loading, power-off overtime and burning.
(3) In order to protect grabs from high temperature, Electro motors should not work continuously beyond 1 minute when grabs are closed and opened.
(4) Grab hydraulic system should not be protect overtime.
   In order to protect equipments against damage.
(5) Don’t rapidly collide with materials.
(6) In order to load materials up to the maximum, grab should be operated on the horizontal line.
(7) In order to easily close, grabs should lift a little when grab closes
(8) At anytime, cable can not haul electric-plug.
(9) Stop operating immediately when cables can not be winded up.Pay attention to cables because of electricity.
(10) Either in manual operation mode or automatic operation mode, the cable-winding drum and speed ballast can only rewind the cable and steel rope. The cable or steel rope can be unwound by weight over 150 Kg.
(11) The control circuit integrates a phase sequence relay. Keep the phase sequence correct in replacing the motor or cable of the cable drum or speed ballast.
(12) Timely close the door of switch box after box operation and fasten its handle.
(13) The open and close delay of grab bucket can be adjusted by resetting their time relay.
2. Operating instruction
2.1. First time to start-up
—Check existing voltage with those of the grab required.
—Check the hydraulic oil level
     Refill oil which may have been lost during transportation
—At temperatures below -10°C, either preheat the hydraulic oil or operate the closed grab(locked against opening)until the oil has warmed up to 0°C
-Check the SWL of the crane.
-Remove the protective caps from plug and socket outlets
-Connect the electric plug in device of grab and cable. If the motor rotates into the wrong direction, interchange terminal leads. Should the grab be supplied without assembled electrical device connect an adequate device according to the wiring-diagram.
-Fit cable tension release, keep care that rubber hose does not stress the electrical plug in device.
-After approx.50 operational hours clear hydraulic oil filter.
2.2. Daily start-up
-Check oil level
-At temperatures below -10°C, either preheat the hydraulic oil or operate the closed grab (locked against opening) until the oil has warmed up to 0°C
-Check plug in device and cable tension release to proper fit.
-Check whether bolted connections, hoses, lifting cylinders, plug-in device or cable lead-throng are tight.
  The grab is can’t be used underwater.
3.1. Hydraulic-oil change
First oil changes after 500 working hours. Further oil changes after every 1000 working hours, or at latest one year.
Oil types see sheet 3.8 Oil recommendation
1.Set the grab in open position
  2.Open ventilation (by removing oil level indicator)
  3.Remove and clean oil filter and refit
  4.Drain oil
  5.Clean or change oil filter and refit
  6. Connect oil drain
  7.Fill tank
  8. Close grab
  9.Check Hydraulic-oil level
3.2. Lubrication
  See Illustration
  Creasing point G daily
  Creasing point H daily
  Creasing point I every 6 months
  Creasing point K every week
3.3.Oil filter
  Oil filter must be cleaned after 50 hours, 100 hours and thereafter every 200 working hours or after repairs or check of hydraulic unit, hoisting cylinders.
3.4. Motor
    Please inquire ABB about maintenance
3.5. Daily checks
3.5.1. Oil level check
-Oil level is to be checked when grab is closed and piston rods are retracted.
-Grab must be in correct vertical position.
-Check oil level indicator for max. Or min. oil level.
-Too much oil will lead to an excessive pressure in the tank.
-Insufficient oil can cause overheating in the hydraulic system and could damage the pump.
-Top up with oil previously used c.f. Oil recommendation.
3.5.2. Oil pressure check and adjustment
  Oil pressure should be checked at the following points:
  With cover being mounted opening pressure on hoist cylinder measuring point MB<=130bar and closing pressure on hoist cylinder MA<=200bar.
  With cover not being mounted opening pressure on control block measuring point MB and closing pressure on control block point MA. The cover must be removed to adjust the oil pressure. Adjusting the pressure limit valve DV2 regulates opening oil pressure. Adjusting the pressure limit valve DV1.After adjustment the cover should be replaced regulates closing oil pressure.
3.6. Other checks
-Check high pressure hoses for damage.
-Check tightness of screw joints and hoist cylinders.
-Check screwed connections.
-Check bearings for wear.
-Check electric cable connection and cable release.
3.7. Repair
  When repairing the grab notice the following:
  Make grab current less. After every dismounting res. Repair check the oil pressure according to the max. oil pressure shown on the type plate. Adequate test manometers will be used.
3.8. Table of recommended hydraulic fluids
  For normal operation, a hydraulic fluid of viscosity class ISO VG46 is recommended (containing a wear-inhibiting additive)