5576368-5.3 Functional description LDCL [PDF]

Zitiervorschau

MAN Diesel & Turbo Item Name:

Info. No.: Copyright  2013 MAN Diesel & Turbo, branch of MAN Diesel & Turbo SE, Germany registered with the Danish Commerce and Companies Agency under CVR-no. 31611792 (referred to as “MAN Diesel & Turbo”).

375633

Item Id.:

Jacket cooling water system

Size: Product Type:

Scale:

5576368-5 Projection:

A4

Page No.:

LDCL

Date

Des.

Chk.

20130801 20131120 20131129 20140514

JYA DFA DFA KELL

MFA KELL KELL OLS

A.C.

1 (4) Revision Change

Chg. Not.

Z4 Figure 1. updated. Z4 Figure 1 and 2 updated. “Function” section, Figure 1 and 2 updated.

Rev.

00 01 02 03

Load Dependent Cylinder Liner (LDCL) Cooling Water System Purpose Under very low engine load the temperature in the cylinder becomes relatively low and this causes the sulphur from the fuel oil to condensate on the cylinder liner wall which will cause corrosion. The purpose of the LDCL cooling water system is to raise the temperature on the cylinder liner wall to prevent the condensation of the sulphur. Raising the temperature of the cylinder liner wall is done by raising the jacket cooling water temperature at low load. This will cause the cylinder liner wall to have a higher temperature and thus, the condensation of sulphur will be reduced.

This drawing is the property of MAN Diesel & Turbo and is to be treated as confidential by the party to whom it has been submitted by MAN Diesel & Turbo, and may not be disclosed to any third party without the specific prior written permission of MAN Diesel & Turbo.

Function The LDCL cooling water system differs from the normal system by having a circulation circuit of cooling water over the cylinder liners. The circulation is driven by an engine installed circulation pump to ensure a high flow over the liners. This pump is operative during the entire engine load spectrum i.e. 0% → 100% engine load. The circulation circuit is cooled by removing hot water from the circuit and adding cold, corresponding to the heat release of the cylinder liner and the temperature set point in the control system. In case of failure in the system, the circulation pump will stop and the engine installed 3way mixing valve will move to fail safe position which is full open 3(B) – 1(AB). In this position, the full flow of cooling water from the ship is sent through the liners and the cooling water temperature will be controlled by the ships cooling water supply.

MAN Diesel & Turbo Item Name:

Info. No.: Copyright  2013 MAN Diesel & Turbo, branch of MAN Diesel & Turbo SE, Germany registered with the Danish Commerce and Companies Agency under CVR-no. 31611792 (referred to as “MAN Diesel & Turbo”).

375633

Item Id.:

Jacket cooling water system

Size: Product Type:

Scale:

5576368-5 Projection: Page No.:

A4

LDCL

Date

Des.

Chk.

20140514

KELL

OLS

A.C.

2 (4) Revision Change

Chg. Not.

“Function” section, Figure 1 and 2 updated.

Rev.

03

This drawing is the property of MAN Diesel & Turbo and is to be treated as confidential by the party to whom it has been submitted by MAN Diesel & Turbo, and may not be disclosed to any third party without the specific prior written permission of MAN Diesel & Turbo.

Figure 1: Schematic of the LDCL cooling water system

Control The Cooling Water Control Unit (CWCU) measures inlet and outlet temperatures, inlet and outlet pressures for the circulation pump and the actual engine load. Based on these inputs, the 3-way mixing valve is moved to a position where the temperature of the circulating cooling water matches the inlet and outlet temperatures defined by the systems parameters (refer to figure Figure 2: Expected cooling water temperature vs. engine load). In addition, the CWCU will order an inlet temperature from the ships cooling water system, which again is defined by the systems parameters (indicated in Figure 2).

MAN Diesel & Turbo Item Name:

Info. No.: Copyright  2013 MAN Diesel & Turbo, branch of MAN Diesel & Turbo SE, Germany registered with the Danish Commerce and Companies Agency under CVR-no. 31611792 (referred to as “MAN Diesel & Turbo”).

375633

Item Id.:

5576368-5

Jacket cooling water system

Size: Product Type:

Scale:

Projection: Page No.:

A4

LDCL

Date

Des.

Chk.

20140514

KELL

OLS

3 (4)

A.C.

Revision Change

Chg. Not.

“Function” section, Figure 1 and 2 updated.

Rev.

03

LDCL PRINCIPLE Temperatures vs. Engine Load

[deg.C]

130 125 120 115 110 105

Load Dependent Variable Temperature

100 95

Tout TT-8413

90 85

Tldvt (reg. value) TT-8414

80

Tin TT-8407

75 70

This drawing is the property of MAN Diesel & Turbo and is to be treated as confidential by the party to whom it has been submitted by MAN Diesel & Turbo, and may not be disclosed to any third party without the specific prior written permission of MAN Diesel & Turbo.

65 60 0

10

20

30

40

50

60

70

80

90

100 Engine Load [%]

Figure 2: Expected cooling water temperature vs. engine load (principle)

In case of a sensor failure or if the circulation pump starter cabinet is put in Local Control, an alarm will be raised, and the system returns to fail safe state.

MAN Diesel & Turbo Item Name:

Info. No.: Copyright  2013 MAN Diesel & Turbo, branch of MAN Diesel & Turbo SE, Germany registered with the Danish Commerce and Companies Agency under CVR-no. 31611792 (referred to as “MAN Diesel & Turbo”).

375633

Item Id.:

Jacket cooling water system

Size: Product Type:

Scale:

5576368-5 Projection: Page No.:

A4

LDCL

Date

Des.

Chk.

20140514

KELL

OLS

A.C.

4 (4) Revision Change

Chg. Not.

“Function” section, Figure 1 and 2 updated.

Rev.

03

User interface The stand-alone implementation of the CWCU has a single common alarm output for the ships alarm system and a local status indication. The status indication consists of 3 lamps and 2 buttons: Alarm: A red light indicates an active alarm. The circulation pump is stopped and the high temperature circulation is inoperative. Action required to find and correct the problem. Un-acknowledged alarm: An alarm has occurred but the alarm condition is no longer present. Action required to acknowledge the alarm by pressing the blue button to re-activate the system.

This drawing is the property of MAN Diesel & Turbo and is to be treated as confidential by the party to whom it has been submitted by MAN Diesel & Turbo, and may not be disclosed to any third party without the specific prior written permission of MAN Diesel & Turbo.

System OK: No alarms, and the system is operative.

Acknowledge button (on or inside the cabinet): After an alarm condition has been rectified, the button must be pressed to re-activate the system.

Lamp test button

Please note that acknowledging an un-acknowledged alarm will start the circulation pump if no other alarms are active!