A casting system for a flywheel of a marine diesel engine

Abstract

The invention discloses a casting system for a marine diesel engine flywheel, comprising a sprue, an entgate, an annular riser, an anti-scouring brick, a slag collecting trough, a cross runner and an annular tie bar, wherein a plurality of cross runners are radially arranged, the inner end of the cross runner is connected to the lower part of the sprue, the outer end of the cross runner is connected to the annular riser, an annular tie bar is arranged at the bottom of the annular riser, and a plurality of entgates are vertically arranged on the cross runner, and the plurality of entgates include an inner entgate and an outer entgate. The application of this casting system has an obvious slag collecting effect on the inclusions in the molten iron, and can effectively prevent impurities from entering the flywheel casting cavity. At the same time, the annular tie bar and the annular riser are arranged at the tooth position, which can effectively prevent the tooth shape from being deformed, ensure the tooth casting accuracy, and also ensure the loose defects on the upper surface of the tooth caused by insufficient shrinkage compensation, thereby improving the flywheel casting quality and reducing the rework rate.

Description

Technical Field

[0001] The invention relates to a casting technology for large ship parts, in particular to a casting system for a flywheel of a marine diesel engine. Background Art

[0002] The flywheel is a key component of a marine diesel engine. It has sufficient moment of inertia to maintain the force balance and inertia of the ship's shaft system. At present, the flywheel material for large marine diesel engines is generally ductile iron, and the weight of the blank is generally above 5t. The tooth shape is required to be a cast tooth (non-machined surface), and the upper and lower end surfaces of the tooth shape are machined surfaces. However, in the actual production process, obvious pits and other defects often appear on the upper surface of the flywheel tooth shape after shot blasting and other processing. After analysis, it is found that the loose defects are caused by insufficient shrinkage compensation; the dimensional accuracy of the cast teeth is not accurately controlled, and some teeth are deformed, resulting in the meshing of the teeth not meeting the standards during the flywheel test run. The quality problems caused by the above defects will affect the appearance of the casting, increase the rework rate of the casting, and even cause the casting to be scrapped, greatly increasing the production and manufacturing costs. Summary of the invention

[0003] In order to overcome the deficiencies of the prior art, the object of the present invention is to provide a casting system for a marine diesel engine flywheel, which can solve the above-mentioned problems.

[0004] The purpose of the present invention is achieved by the following technical solutions:

[0005] A casting system for a marine diesel engine flywheel, the casting system comprising an annular riser, a straight runner located at the center of the annular riser, and a plurality of radially arranged cross runners connecting the annular riser and the straight runner, the inner ends of the plurality of cross runners are connected to the lower part of the straight runner, the outer ends of the cross runners are connected to the annular riser, an annular tie bar is arranged at the bottom of the annular riser, a plurality of ingates are vertically arranged on the cross runner, the plurality of ingates include an outer ingate connected between the outer end of the cross runner and the annular tie bar, and the ingates also include a plurality of inner ingates on the plurality of cross runners connected between the annular riser and the straight runner.

[0006] Preferably, the outer ingrown is arranged between the upper part of the outer end of the cross runner and the lower part of the annular tie bar.

[0007] Preferably, the distances between the plurality of inner ingates and the straight runner are equal, and the upper ports of the inner ingates are connected to the flywheel casting cavity.

[0008] Preferably, a slag collecting trough is provided at the bottom end of the sprue, and an anti-collision brick is provided below the slag collecting trough.

[0009] Preferably, five cross runners are arranged radially with equal angles.

[0010] Preferably, the diameter of the straight runner is larger than the diameter of the inner ingrown runner, and the diameter of the inner ingrown runner is larger than the diameter of the outer ingrown runner.

[0011] Preferably, the length of the straight runner is greater than the length of the inner ingrown runner, and the length of the inner ingrown runner is less than the length of the outer ingrown runner.

[0012] Preferably, the thickness of the annular tie bar is 10 mm to 20 mm, and is adjusted to match the size of the flywheel casting model. The annular coverage of the annular tie bar is 1 / 2 to 2 / 3 of the flywheel tooth surface.

[0013] Preferably, the height of the annular riser is 1 / 3 to 1 / 2 of the thickness of the flywheel tooth, and the contact width a between the annular riser and the annular tie rod is a=20 mm to 40 mm.

[0014] Compared with the prior art, the beneficial effect of the present invention is that the application of the pouring system has an obvious slag collection effect on the inclusions in the molten iron, and can effectively prevent impurities from entering the flywheel casting cavity. At the same time, the tooth position is provided with annular tie bars and annular risers, which can effectively prevent the tooth shape from being deformed, ensure the tooth casting accuracy, and ensure the loose defects on the upper surface of the tooth caused by insufficient shrinkage compensation, thereby improving the flywheel casting quality and reducing the rework rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A schematic diagram of a casting system for a marine diesel engine flywheel according to the present invention;

[0016] Figure 2 It is a schematic diagram of the three-dimensional structure application of the gating system in the flywheel casting;

[0017] Figure 3 It is a top view of the application of the gating system in the flywheel casting;

[0018] Figure 4 for Figure 3 Half section of the gating system at AA in the middle;

[0019] Figure 5 A half-section diagram of the application of the gating system in flywheel castings;

[0020] Figure 6 for Figure 5 A partial enlarged view of the flywheel casting tooth shape at point B in the middle.

[0021] In the figure: 1. straight pouring channel; 3. annular riser; 4. anti-impact brick; 5. slag collecting trough; 6. horizontal pouring channel; 7. annular tie rod; 8. flywheel; 9. teeth; 21. outer ingating channel; 22. inner ingating channel. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] See also Figures 1 to 6 The present application discloses a casting system for a marine diesel engine flywheel, the casting system comprising: a sprue 1, an annular riser 3, an anti-impact brick 4, a slag collecting trough 5, a cross runner 6 and an annular tie rod 7.

[0024] Connection relationship: corresponding to the flywheel 8 and its teeth 9 , the pouring system includes an annular riser 3 , a sprue 1 located at the center of the annular riser 3 , and a plurality of radially arranged cross runners 6 connecting the annular riser 3 and the sprue 1 .

[0025] See also Figure 1 The inner end of the runner 6 is connected to the lower part of the sprue 1 , and the outer end of the runner 6 is connected to the annular riser 3 .

[0026] An annular tie bar 7 is arranged at the bottom of the annular riser 3, and a plurality of ingates are vertically arranged on the cross runner 6. The plurality of ingates include an outer ingates 21 arranged between the outer end of the cross runner 6 and the annular tie bar 7, and the ingates also include a plurality of inner ingates 22 arranged on the plurality of cross runners 6 between the annular riser 3 and the straight runner 1.

[0027] A slag collecting trough 5 is connected to the bottom end of the sprue 1, and an anti-collision brick 4 is connected and arranged below the slag collecting trough 5. The slag collecting trough 5 is a square structure and plays a role in collecting slag; the role of the anti-collision brick 4 is to prevent the molten iron from being eroded by sand due to gravity, thereby causing quality defects such as sand holes.

[0028] The outer ingrate 21 is arranged between the upper part of the outer end of the runner 6 and the lower part of the annular tie bar 7 .

[0029] Furthermore, the distances between the plurality of inner ingates 22 and the sprue 1 are equal, and the upper ends of the inner ingates 22 are connected to the flywheel casting cavity.

[0030] In one embodiment, five cross runners 6 are arranged radially at equal angles and are evenly distributed in a five-equal circular array; the number of the inner ingrowns 22 and the outer ingrowns 21 is the same as that of the cross runners 6, five each, for a total of ten.

[0031] Furthermore, the diameter of the sprue 1 is larger than the diameter of the inner ingrowth 22 , and the diameter of the inner ingrowth 22 is larger than the diameter of the outer ingrowth 21 , so as to adapt to the reasonable flow direction and resistance impact of the molten metal fluid mechanics.

[0032] Furthermore, the length of the sprue 1 is greater than the length of the inner ingrown channel 22 , and the length of the inner ingrown channel 22 is less than the length of the outer ingrown channel 21 .

[0033] The thickness of the annular tie bar 7 is 10mm~20mm, and is adjusted according to the size of the flywheel casting model. The annular coverage area of ​​the annular tie bar 7 is 1 / 2~2 / 3 of the flywheel tooth surface; the height of the annular riser 3 is 1 / 3~1 / 2 of the flywheel tooth thickness, and the contact width a between the annular riser 3 and the annular tie bar 7 is a=20mm~40mm.

[0034] Flow direction and working principle of poured molten metal: After the sand mold of flywheel 8 is completed, during pouring, molten metal enters from sprue 1 until it fills slag collecting trough 5 at the bottom of sprue 1, and then molten metal flows through runner 6 and enters into casting cavity of flywheel 8 through ingrowth; finally, after pouring, annular tie rod 7 at tooth 9 plays the role of preventing tooth 9 from deforming, and annular riser 3 plays the role of compensating the upper surface of tooth shape of tooth 9.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A casting system for a marine diesel engine flywheel, the casting system comprising an annular riser (3), a sprue (1) located at the center of the annular riser (3), and a plurality of radially arranged runners (6) connecting the annular riser (3) and the sprue (1), wherein the inner ends of the plurality of runners (6) are connected to the lower part of the sprue (1), and the outer ends of the runners (6) are connected to the annular riser (3). Features: An annular tie bar (7) is arranged at the bottom of the annular riser (3), and a plurality of ingates are arranged vertically on the runner (6). The plurality of ingates include an outer ingates (21) arranged between the outer end of the runner (6) and the annular tie bar (7), and the ingates also include a plurality of inner ingates (22) arranged on the plurality of runners (6) between the annular riser (3) and the straight runner (1).

2. The pouring system according to claim 1, Features: The outer ingrate (21) is arranged between the upper part of the outer end of the runner (6) and the lower part of the annular tie bar (7).

3. The pouring system according to claim 1, Features: The distances between the plurality of inner ingrows (22) and the straight runner (1) are equal, and the upper ports of the inner ingrows (22) are connected to the flywheel casting cavity.

4. The pouring system according to claim 1, Features: A slag collecting trough (5) is provided in communication with the bottom end of the sprue (1), and an anti-collision brick (4) is provided below the slag collecting trough (5).

5. The pouring system according to claim 1, Features: The cross runners (6) are arranged in five radial directions with equal angles.

6. The pouring system according to claim 1, Features: The diameter of the straight runner (1) is greater than the diameter of the inner ingrown runner (22), and the diameter of the inner ingrown runner (22) is greater than the diameter of the outer ingrown runner (21).

7. The pouring system according to claim 6, Features: The length of the straight runner (1) is greater than the length of the inner ingrown runner (22), and the length of the inner ingrown runner (22) is less than the length of the outer ingrown runner (21).

8. The pouring system according to claim 1, Features: The thickness of the annular tie bar (7) is 10 mm to 20 mm, and is adjusted according to the size of the flywheel casting model. The annular coverage of the annular tie bar (7) is 1 / 2 to 2 / 3 of the flywheel tooth surface.

9. The pouring system according to claim 1, Features: The height of the annular riser (3) is 1 / 3 to 1 / 2 of the thickness of the flywheel tooth, and the contact width a between the annular riser (3) and the annular tie rod (7) is a=20 mm to 40 mm.

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