Replacing Hydraulic Hose Lines

Interval

4 Years(s) Real time

Component

All hydraulic hose lines

According to the Main Association of Industrial Associations of Germany, hydraulic hose lines must not be used for more than six years, including a maximum two-year storage period.

Hydraulic hose lines are marked with the following information:

  • Manufacturer's code
  • Date of manufacture (month and year)
  • Maximum dynamic operating pressure

We recommend that all hose lines are replaced every four years.

Combine the changing of the hose lines with the oil change. Proceed as follows:

  • Empty and clean hydraulic reservoir.t
  • Replace hose lines.
  • Top up oil in the hydraulic reservoir.
  • Running in and vent the oil consumers.

Consumable

Hydraulic oil HLP 46 to DIN 51524, Part 2 (ISO-L-HM 46 to ISO 6743, Part 4) Purity class ISO 4406-18/16/13

Disimilar lubricants can contain various additives that might not be compatible. To rule out incompatibility between the lubricants, disimilar lubricants must not be mixed. If you have any questions, please contact your lubricant supplier.

For hose lines with ordering data, see the media diagram (MP).

Used oil and oily hose line should be regarded as hazardous waste. Dispose of these materials and components according to the locally applicable regulations.

15 litre container

Making hose lines accessible

Please observe chapter 4.2 "Special safety measures" when entering or leaving the machine. Danger to life within the traversing range of the gantry loader. Before climbing onto the machine, always move the portal loader to its parking position, switch off and secure to prevent it being switched on again. Do not remove gantry loader padlock before end of work or before removing the ladder.

Step 1:

There should be no tool in the tool spindle.

Step 2:

Machining unit traversed into support position.

Step 3:

Z-axis (rotary table) moved away from the machining unit.

Step 4:

Work area safety door open and secured to prevent closing.

Step 5:

Loading hatch closed.

Step 6:

Machine switched off at main switch and secured against being switched on again.

Step 7:

Compressed air shut-off valve closed and secured to prevent opening.

Step 8:

Maintenance area safety door opened and secured to prevent closing.

Step 9:

Machining unit protected from falling by supports.

Step 10:

Maintenance opening B open.

Step 11:

Gantry loader in parking position, switched off and secured against being switched on again.

Step 12:

Unscrew Z-concertina cover from rotary table and push onto the XY cover in the direction of the arrow. The connections of the hose lines become accessible.

Replacing Hose lines

When the hydraulic unit is switched off, various levels of pressure remain inside different sections of the line. Do not use the manual trigger of directional control valves to release residual pressure from the line. Do not readjust the directional control valves to ensure that upon restart, pressure is initially applied to the same side of the hydraulic cylinders as before. The cylinder will then be filled without piston movement. Otherwise, the piston will not be cushioned when travelling in the opposite direction against the end stop due to lacking counter-pressure. Lines containing residual pressure may be unscrewed carefully; pressure will be relieved quickly with the first drops escaping from the line. You must only continue to carefully drain the nominal volume of accumulator before completely releasing the hoses if the machine is fitted with an accumulator option. Use the media diagram to check whether this applies to your machine.

Procedure

Per hose line:

  • Remove all fixings.
  • Use a container to collect the oil from the line.
  • Carefully loosen the duct union on the hose line until oil drips from the line. Carefully allow the oil to drain until the hose is relieved.
  • Unscrew hose line, drain the oil.
  • Clean the thread with a lint-free cloth.
  • Screw tight new hose line.
  • Fit all fixings.

Open compressed air shut-off valve.

Running in and venting the oil consumers

After the hose line has been replaced, the system contains air. This will make hydraulic movements jerky. To vent the system, all parts must be moved back and forth several times without a workpiece or tool. As a result, the air is evacuated via the tank line.

Step 1:

Oil in the hydraulic reservoir filled to maximum mark on oil level indicator.

Step 2:

Axial piston pump filled.

Step 3:

Remove support from the machining unit.

Step 4:

Before closing the safety doors and maintenance openings, ensure that nobody is behind the guard panels. Close the work area safety door and the maintenance area safety door. Close maintenance opening B.

Step 5:

Turn on machine on at the main switch.

Step 6:

Switch on motors. The hydraulic unit will run.

Step 7:

Repeatedly enable all hydraulic movements with individual functions backwards and forwards.

Checking for leaks and preparing machine for operation

Step 1:

Make hose lines accessible again:

  • Open work area safety door and secure to prevent closing.
  • Open maintenance area safety door and secure to prevent closing.
  • Switch off machine and secure to prevent restart.
  • Support machining unit.
  • Open maintenance opening B.

Step 2:

Check the duct unions of the hydraulic hose lines for leaks.

Step 3:

Check the oil level inside the hydraulic reservoir on the oil level indicator. Fill with oil up to maximum mark.

Step 4:

Screw Z-axis concertina cover to the rotary table.

Step 5:

Remove support from the machining unit.

Step 6:

Before closing the safety doors and maintenance openings, ensure that nobody is behind the guard panels. Close the work area safety door and the maintenance area safety door. Close maintenance opening B.

Step 7:

Switch the machine on.

Step 8:

Place a tool in the tool spindle to protect the tool spindle from the ingress of dirt.

Step 9:

Switch off motors.

Step 10:

Remove gantry loader padlock.