JPH08326537A - Cooling water discharging device for water-cooled type internal combustion engine - Google Patents

Abstract

PURPOSE: To improve maintainability and to reduce a working cost by providing a cooling water bleeding valve on the inlet side, a cooling water bleeding valve on the outlet side, and a cooling water branch pipe on-off valve to open and close a cooling water inlet line to each cylinder jacket. CONSTITUTION: During inspection and maintenance of an engine, the cooling water branch pipe on-off valve 21a of a cylinder 50 is opened and the on-off valve 21 of other cylinder is closed. With this state, a cooling water bleeding valve 9 on the outlet side is opened and a cooling water bleeding valve 8 on the inlet side is switched in such a manner to intercommunicate a drain pipe 20 and a cooling water discharge pipe 7. Through the operation, cooling water in a cylinder 50 to perform inspection and maintenance and cooling water in a cooling water common inlet line 1 and an outlet line 2 are outputted to a cooling water discharge pipe 7 through the cooling water bleeding valve 8 on the inlet side and the cooling water bleeding valve 9 on the outlet side. Thus, cooling water in a cylinder jacket 5 not to need inspection and maintenance remains in an engine. This constitution reduces a maintenance cost and a working cost.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-cooled internal combustion engine, and more particularly to a water-cooled large diesel engine, and more particularly to a cooling water discharge device for discharging cooling water to the outside of the machine during inspection and maintenance of the engine.

[0002]

2. Description of the Related Art Large-scale diesel engines for ships, stationary vessels, etc. are equipped with a cylinder jacket and a cooling water discharge device for discharging the cooling water in a cooling water pipe to the outside when the engine is inspected and maintained. ing.

FIG. 2 shows a cooling water system diagram of a large diesel engine equipped with such a cooling water discharge device.

In FIG. 2, 1 is a cooling water inlet common pipe, 2 is a cooling water outlet common pipe, 5 is an engine cylinder jacket, 3
Is a cooling water inlet branch pipe branched from the cooling water inlet common pipe 1 and connected to each cylinder jacket 5. Reference numeral 4 is a cooling water outlet connecting the cooling water outlet of each cylinder jacket and the cooling water outlet common pipe 2. It is a branch pipe.

Reference numeral 6 is an expansion joint provided in the cooling water outlet branch pipe line 4, and reference numeral 18 is a cooling water return pipe branched from the cooling water outlet common pipe 2 and connected to an expansion tank (not shown). Reference numeral 7 denotes a cooling water discharge pipe, which is the common pipe 1 for the cooling water inlet.
It is connected to a drain pipe 20 branched from the above and two drain pipes 10 and 11 branched from the cooling water outlet common pipe 2, respectively.

Reference numeral 9 indicates a common pipe 2 for cooling water outlet and two drain pipes 1.
An outlet side cooling water drain valve for opening and closing between 0 and 11 is provided at a confluence point of the drainage pipe 20 on the cooling water inlet common pipe 1 side and one of the drainage pipes 11 on the cooling water outlet common pipe 2 side. Is provided,
This is a three-way valve type inlet side cooling water drain valve that switches the connection between these two drain pipes and the cooling water discharge pipe.

Reference numeral 12 is a bypass pipe for connecting the cooling water inlet common pipe 1 and the cooling water outlet common pipe 2 by bypassing the cylinder jacket 5, and 13 is a bypass adjusting valve for adjusting the amount of water to the bypass pipe 12. .

In the above conventional water-cooled diesel engine, when the engine is inspected and maintained, the inlet side cooling water drain valve (three-way valve) 8 is connected to the drain pipe 20 and the cooling water discharge pipe 7, The drain pipe 11 side is set to be closed, and the outlet side cooling water drain valve 9 on the cooling water outlet common pipe 2 side is set.
To open.

As a result, all the cooling water in the cylinder jacket 5 of the engine and the cooling water inlet system pipeline and the outlet system pipeline are discharged from the cooling water discharge pipe 7 to the outside.

[0010]

In the conventional water-cooled diesel engine described above, when the engine is inspected and maintained as described above, it is present in the cylinder jacket 5 and the cooling water pipe line of the engine. All cooling water to be discharged is discharged to the outside.

For this reason, the inspection for a specific one cylinder,
Even when performing maintenance, it is necessary to replenish the cooling water for all cylinders when the engine is restarted because all the cooling water is extracted. In particular, since cooling water usually contains a rust preventive agent, it takes a lot of man-hours and cost to replenish the cooling water, which lowers the maintainability of the engine and raises the operating cost.

An object of the present invention is to provide a water-cooled internal combustion engine in which maintainability is improved and operation cost is reduced by reducing man-hours and costs for inspecting and drawing out and replenishing cooling water during maintenance of the engine. It is to be.

[0013]

SUMMARY OF THE INVENTION According to the present invention, a cooling water discharge pipe connected to a cooling water inlet common pipe and a cooling water outlet common pipe, respectively, and between the both common pipes and the discharge pipe, respectively. In addition to having two cooling water drain valves that open and close, each cooling water inlet branch pipe to the cylinder jacket is provided with an opening and closing valve that opens and closes this pipe line, so that only one specific cylinder can be inspected and maintained. Is that the opening / closing valve for the cooling water inlet branch pipe to the cylinder is opened so that the cooling water can be extracted only from this cylinder, and the amount of replacement of the cooling water is reduced.

In this case, preferably, in addition to the above, a cooling water inlet valve for opening and closing the inlet common pipe is provided upstream of a branch portion of the cooling water inlet common pipe to the cylinder jacket to the cooling water inlet branch pipe. Along with the provision of the cooling water outlet valve, it is preferable to provide a cooling water outlet valve for opening and closing the cooling water outlet common pipe.

[0015]

Since the present invention is configured as described above, when inspecting or servicing a particular cylinder, only the cooling water branch pipe on-off valve of that cylinder is opened and the on-off valves of other cylinders are closed. Open the cooling water drain valve and drain the cooling water only from the jacket of the cylinder.

As a result, the cooling water is not discharged from the other cylinders, and the replacement of the cooling water in these cylinders becomes unnecessary, and the amount of replacement of the cooling water is greatly reduced compared to the conventional one. In addition, since it is not necessary to discharge the cooling water from all the cylinders, the valve can be operated easily.

[0017]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 shows a cooling water system diagram of a large water-cooled diesel engine according to an embodiment of the present invention.

In FIG. 1, 1 is a cooling water inlet common pipe connected to a cooling water pump (not shown), and 2 is a cooling water outlet common pipe. The pipe 3 is branched and connected to each cylinder jacket 5. Reference numeral 21 denotes a cooling water branch pipe opening / closing valve which is provided in each of the cooling water inlet branch pipes 3 and opens and closes the same.

Reference numeral 4 denotes a cooling water outlet branch pipe that connects the cooling water outlet of each cylinder jacket and the cooling water outlet common pipe 2, and the cooling water after engine cooling passes through the branch pipe 4 and the cooling water outlet common pipe. It is designed to merge into 2.

Reference numeral 6 is an expansion joint for absorbing thermal deformation provided in the cooling water outlet branch pipe line, and 18 is cooling water branched from the cooling water outlet common pipe 2 and connected to an expansion tank (not shown). The return pipe 16 is an opening / closing valve of the return pipe 18. Reference numeral 12 denotes a bypass pipe that connects the cooling water inlet common pipe 1 and the cooling water outlet common pipe 2 by bypassing the cylinder jacket 5.
Is a bypass adjusting valve for adjusting the amount of water to the bypass pipe 12.

Reference numeral 7 denotes a cooling water discharge pipe, which has a downstream end of a drain pipe 20 branched from the cooling water inlet common pipe 1 and two drain pipes 10 branched from the cooling water outlet common pipe 2.
The downstream ends of 11 are connected to each other.

Reference numeral 9 denotes an outlet side cooling water drain valve which opens and closes between the cooling water outlet common pipe 2 and the pipelines to the two drainage pipes 10 and 11, and 8 denotes drainage on the cooling water inlet common pipe 1 side. A three-way valve type inlet provided at a confluence of the pipe 20 and one of the drain pipes 11 on the common side of the cooling water outlet and switching connection between these two drain pipes 10 and 11 and the cooling water discharge pipe 7. This is the side cooling water drain valve.

A cooling water inlet valve 14 for opening and closing the cooling water inlet common pipe 1 is provided upstream of the cooling water inlet common pipe 1, and cooling water for opening and closing the cooling water outlet common pipe 2 is provided downstream of the cooling water outlet common pipe 2. Outlet valve 1
5 are provided respectively. Reference numeral 17 is an opening / closing valve of the air suction pipe.

During operation of the engine having the cooling system configured as described above, the cooling water inlet valve 14, the cooling water outlet valve 15, the return pipe 18 opening / closing valve 16, and the bypass adjusting valve 13 are provided.
And all the cooling water branch pipe on-off valves 21 of each cylinder are opened,
The outlet side cooling water drain valve 9 is closed, the inlet side cooling water drain valve 8 is closed on the drain pipe 20 side, and the air intake pipe opening / closing valve is also closed.

As a result, the cooling water flows from the cooling water inlet valve 14 to the cooling water inlet common pipe 1 as shown by the broken line in FIG.
Through each cooling water inlet branch pipe 3 and the opening / closing valve 21 thereof to enter each cylinder jacket 5.

The cooling water whose temperature has been raised by cooling the engine merges in the cooling water outlet common pipe 2 through the cooling water outlet branch pipe 4, and is sent to the outside such as a cooling water expansion tank via the cooling water outlet valve 15. To be done.

When inspecting or servicing the engine, for example, when inspecting or servicing the central cylinder 50, the cooling water branch pipe on-off valve 21a of the cylinder is opened and the on-off valves 21 and 22 of the other cylinders are closed. And Further, the cooling water inlet valve 14, the cooling water outlet valve 15, and the return pipe opening / closing valve 16 on the cooling water inlet common pipe 1 side are closed, respectively, and the air intake pipe opening / closing valve 12 is opened.

In this state, the outlet side cooling water drain valve 9 is opened and the inlet side cooling water drain valve (three-way valve) 8 is connected to the drain pipe 2.
0 and the cooling water discharge pipe 7 are switched so as to communicate with each other. By this operation, the cooling water in the cylinder 50 to be inspected and maintained, and the cooling water in the cooling water common inlet pipe line 1 and the outlet pipe line 2 flow as shown by solid arrows in FIG. It is led out to the cooling water discharge pipe 7 through the water drain valve 8 and the outlet side cooling water drain valve 9.

Therefore, the cooling water in the cylinder jackets 5 of other cylinders (cylinders on the left and right of the cylinder 50, etc.) that do not require inspection and maintenance will not be discharged and will remain in the engine. There is no need to refill these cylinders with cooling water on entry. As a result, the number of man-hours for exchanging the cooling water of the engine is reduced, the mixing of the rust preventive agent and the like is minimized, and the maintenance cost and the operation cost are reduced.

[0030]

According to the present invention, the cooling water discharge pipe connected to the cooling water inlet common pipe and the cooling water outlet common pipe, and the common pipe of both of them and the discharge pipe are opened and closed, respectively. Since two cooling water drain valves are provided, and an on-off valve for opening and closing this pipeline is provided in each of the cooling water inlet branch pipes to the cylinder jacket, the cylinder of the engine is inspected during maintenance and maintenance. Only the cooling water of the jacket is extracted, and the cooling water of the other cylinders is no longer required, the amount of cooling water exchange is reduced, the number of man-hours for cooling water exchange is reduced, and the amount of expensive rust inhibitor mixed Minimal.

Further, since it is not necessary to discharge the cooling water from all the cylinders, the operation of the cooling water system valve can be simplified. This improves the maintainability of the engine and reduces operating costs.

[Brief description of drawings]

FIG. 1 is a cooling water system diagram of a large water-cooled diesel engine according to an embodiment of the present invention.

FIG. 2 is a diagram of FIG. 1 of a conventional large water-cooled diesel engine.

[Explanation of symbols]

 1 cooling water inlet common pipe 2 cooling water outlet common pipe 3 cooling water inlet branch pipe 4 cooling water outlet branch pipe 5 cylinder jacket 7 cooling water discharge pipe 8 inlet side cooling water drain valve 9 outlet side cooling water drain valve 14 cooling water inlet Valve 15 Cooling water outlet valve 21,21a Cooling water branch pipe opening / closing valve

Claims (1)

[Claims] 1. Cooling water supplied from a cooling water pump into a cooling water inlet common pipe is introduced into each cylinder jacket through a cooling water inlet branch pipe branched from the same inlet common pipe and connected to each cylinder jacket. In a water-cooled internal combustion engine configured to join the cooling water after cooling each cylinder jacket to a cooling water outlet common pipe through a cooling water outlet branch pipe and to send the cooling water to the outside, A cooling water discharge pipe connected to the common outlet pipe, an inlet side cooling water drain valve for opening and closing between the cooling water inlet common pipe and the cooling water discharge pipe, the cooling water outlet common pipe and the cooling water discharge pipe An outlet side cooling water drain valve for opening and closing the pipe, and a cooling water branch pipe opening / closing valve provided in the cooling water inlet branch pipe to each of the cylinder jackets to open and close the pipe. Water-cooled internal combustion engine Cooling water discharge device.