Hans Jensen Lubricators A/S - 100 years

LCD-regulation

Background

LCD regulation ensures a sufficient lubrication when the engine is exposed to load changes, e.g. during manoeuvring. This means that the crew does not have to perform manual adjustments under these conditions. Furthermore, the LCD handle can be used for common joint quantity regulation if there is a need for increasing the oil inlet on all outflows manually.

Functionality

The LCD system receives signals from a governor or a control box connected to the fuel regulation shaft. When load changes occur, e.g. during manoeuvring or similar, these are registered by the LCD system, which thus provides an extra lubrication.

Flexibility

LCD regulation can be specified on new buildings of lubricators. Engine designers have always recommended increased cylinder lubrication during load changes.
The LCD system is standard on all medium-sized and large diesel engines from MAN B&W, but is not used automatically by all licensees.
Therefore, we recommend that you check your specification related to this field.
 
Please feel free to contact us for further information on LCD regulation.

Purpose

LCD regulation is an automatic intersection regulation which automatically ensures a sufficient lubrication when the engine is exposed to load changes. This means that the crew does not have to perform manual adjustments under these conditions. Furthermore, the LCD handle can be used for common joint quantity regulation if there is a need for increasing the oil inlet on all outflows manually.

System description

Load changes are reflected in the position of the fuel regulation shaft. The pick-up of the LCD system detects such changes through the pressure rod and passes this information on to the control box as an electric signal. Alternatively, the signal can be sent directly from the bridge control.

If the change in the position of the fuel shaft is smaller than the preset value, no extra lubrication is made. The reference is an adjustable parameter and can be adjusted in accordance with the set values for the concerned lubricator/vessel.

If the change in the position is larger than the preset value, the lubrication is increased by the control box which switches on the power to the magnet valve, thus changing the air pressure of the actuator. The air pressure inside the actuator turns an eccentrical axel inside the lubricator, which increases the stroke length of all piston pumps inside the lubricator.

Operation of the LCD actuator

The increase of lube oil is adjusted with the two handles of the LCD actuator. The first handle states the minimum stroke length increase and will always be added to the basis stroke length of the lubricator, independent of load changes. The other handle states the maximum stroke length increase requested during load changes.

Please feel free to contact us for further information on LCD regulation.

 

The actuator should be dismounted every 5 years and lubricated with:
Aeroshell Grease 7
Mil-G 23827B or similar product
Code 70149

The drawings no. 805154 and/or no. 805155 in the LCD appendix in the manual must be scrutinised carefully before dismounting. At remounting it must be ensured that the shaft (pos. 6 on drawing no. 805154 and/or no. 805155) is placed in the same position as before it was dismounted. Do not try to dismount the piston (pos. 6 on drawing no. 805154 and/or no. 805155), as special tools are required to remount it.

Please feel free to contact us for further information on maintenance of LCD regulation.

On this page you can find replies to a number of frequently asked questions on LCD regulation. If you find that the replies are incomplete, you are welcome to contact us with a description of your questions or problems. We will do our best to help you.
  • What is the difference between MEP and LCD regulation?
    • MEP regulation is a way to save lube oil while maintaining a safe operational condition during part load. On all engines with timed lubrication an excess of lube oil is used in part load areas. This occurs due to fact that the engine has a RPM dependent injection and the lube oil consumption if specified as a function: g/BHPh of the engine’s load.

      If you operate in part load areas, the MEP regulation may help to adjust the lube oil consumption to the actual need.

      However, LCD regulation is an automatic joint quantity adjustment increasing the lube oil injection in case of changes in the manoeuvring or loads. This means that the cylinder liner is protected by adding a higher feedrate in short periods when it is needed.

  • Can MEP and LCD regulations be applied together?
    • Yes, MEP and LCD regulations can be used together with great advantage. They serve in their own way to achieve an optimum cylinder lubrication of the engine.

  • FThe lube oil consumption is too high in rough sea. What can I do?
    • The LCD actuator of the lubricator functions based on signals which it receives from a governor or from a control box connected to the fuel regulation shaft. At delivery, the signal is set according to the engine designer’s guidelines.

      However, some engines operate under conditions which are different from the average used as basis for the calculation of these guidelines. Therefore, there is also the possibility that you may adjust the settings of the system yourself. We recommend that you consult the relevant material for the control which is used on your engine. In this way, you may perform an adjustment which meets your need for when an increased lubrication is needed.

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