A method and apparatus for reducing the amount of grease injected into a ship propeller cap

Abstract

The application discloses a method and device for reducing the grease injection amount of a ship propeller cap, which changes the structure of the propeller cap, adds a fixed protrusion integrally formed on the inner wall of the propeller cap, installs a baffle on the fixed protrusion, and fixes a round cover at the tail end of the tail shaft, so that the oil injection space is effectively reduced, the grease usage is reduced, and the cleaning workload of the grease in the propeller cap during the disassembly and maintenance of the propeller cap is greatly reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of shipbuilding, and in particular to a method and a device for reducing the amount of grease injected into a ship propeller cap. Background Art

[0002] Keyless propellers are installed using hydraulic nuts. After installation, the hydraulic nuts are tightened to prevent the propeller from falling off the tail shaft. The propeller cap is then installed on the propeller using bolts, and grease is injected into the cap to prevent seawater from entering. Due to the long design length of the propeller cap, the internal space of the cap is large. In order to maintain the designed clearance between the propeller cap and the rudder, the internal space of the cap cannot be reduced by reducing the design length of the propeller cap. As a result, more grease is injected into the cap. However, the cost of ship grease is high, which increases the construction cost of the ship. In addition, the grease injection speed is slow, which delays the ship's construction period. Summary of the Invention

[0003] In view of this, the present invention provides a method and device for reducing the amount of grease injected into a ship propeller cap, so as to solve the problems existing in the above-mentioned background technology.

[0004] A method for reducing the amount of grease injected into a ship propeller cap comprises the following steps:

[0005] S1, design the size of the dome cover according to the size and position relationship of the tail shaft and propeller cap;

[0006] S2. Design the location of the fixing protrusions to be added to the inner wall of the propeller cap according to the dimensions of the propeller cap and the dome cover;

[0007] S3, when casting the propeller cap, according to the designed position of the fixing protrusion, an annular fixing protrusion is extended from the corresponding position of the inner wall of the propeller cap, and the fixing protrusion is integrally injection-molded with the original structure of the propeller cap;

[0008] S4, making the round cover according to the designed round cover size;

[0009] S5. Install the hydraulic nut on the tail shaft. After the hydraulic nut is installed, fix the round cover on the tail end face of the tail shaft so that the round cover rests against the hydraulic nut.

[0010] S6, fixing the baffle to the fixing protrusion extending from the inner wall of the propeller cap. After the baffle is fixed, install the propeller cap on the propeller. The baffle now divides the internal space of the propeller cap into a first space and a second space.

[0011] S7, checking the air tightness of the second space inside the propeller cap. If the air tightness meets the requirements, inject grease into the second space.

[0012] Preferably, the gap between the baffle and the circular cover is at least 30mm after the propeller cap is installed on the propeller in step S6.

[0013] Preferably, the baffle is fixed on the fixing protrusion by a plurality of first bolts which are uniformly distributed in the circumferential direction.

[0014] Preferably, the circular cover comprises a cover plate and a circular tube, the cover plate is provided with bolt holes for fixing the cover plate on the shaft by the second bolt and the third bolt, the diameter of the cover plate is not less than the outer diameter of the circular tube, the inner diameter of the circular tube is greater than the thread diameter of the shaft part and less than the outer diameter of the hydraulic nut, and the length of the circular tube is greater than the designed distance from the rear end surface of the shaft to the hydraulic nut.

[0015] Preferably, in step S7, when detecting the air tightness of the second space in the propeller cap, the air pressure testing device is connected to the oil injection port of the propeller cap through the air pipe, and then the air pump of the air pressure testing device is opened to pump the second space, the pumping is stopped when the pressure displayed on the pressure gauge of the air pressure testing device reaches the set value, and the pressure value displayed on the pressure gauge after holding the pressure for a certain period of time is used to determine whether the air tightness of the second space is qualified.

[0016] Preferably, the diameter of the baffle is greater than the outer diameter of the hydraulic nut.

[0017] Preferably, step S5 and step S6 can be performed synchronously.

[0018] A device for reducing the amount of grease injected into the propeller cap of a ship, which is installed by using the method, comprises a baffle and a circular cover, the inner wall of the propeller cap extends a ring-shaped fixing protrusion, the baffle is fixed on the fixing protrusion by a plurality of first bolts which are uniformly distributed in the circumferential direction, the circular cover is fixed on the shaft by the second bolt and the third bolt, and the circular cover abuts against the hydraulic nut, and the gap between the baffle and the circular cover is at least 30mm.

[0019] The present application has the following beneficial effects:

[0020] 1. By changing the structure of the propeller cap, the present application adds a fixing protrusion to the inner wall of the propeller cap, installs a baffle on the fixing protrusion, divides the internal space of the propeller cap into two parts by using the baffle, reduces the oil injection space, thereby reducing the amount of grease used, and since only part of the space in the propeller cap is filled with oil, the workload of cleaning the oil in the propeller cap during disassembly and maintenance of the propeller cap is greatly reduced.

[0021] 2、The present application can further reduce the amount of grease by fixing the round cover at the tail end of the tail shaft, and preventing the grease from directly contacting the tail end of the tail shaft, and preventing the hydraulic nut from loosening.

[0022] 3、The gap between the baffle and the round cover should be at least 30mm after the installation of the propeller cap, so as to prevent the second bolt and the third bolt from contacting the baffle and ensure the normal operation of the tail shaft. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. Obviously, the drawings described in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0024] Figure 1 is a structural schematic diagram of the present application.

[0025] Figure 2 is a half sectional view of the round cover.

[0026] Figure 3 is an end face view of the round cover.

[0027] The meanings of the reference numerals in the drawings are as follows:

[0028] 1, fixing protrusion, 2, baffle, 3, first bolt, 4, round cover, 41, cover plate, 42, round pipe, 43, bolt hole, 5, second bolt, 6, third bolt, 7, tail shaft, 8, propeller cap, 9, hydraulic nut, 10, propeller, 11, first space, 12, second space. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the present application more clear and obvious, the following will describe the present application by specific embodiments shown in the drawings. However, it should be understood that these descriptions are only exemplary, and are not intended to limit the scope of the present application. In addition, in the following description, the description of the known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present application.

[0030] The terminology used in the present disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting thereof. As used in this disclosure and the appended claims, the singular forms "a," "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the term "and / or," as used herein, refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0031] It should be understood that, although the terms first, second, third, etc. can be used herein to describe various information, but these information should not be limited to these terms, and cannot be understood as indicating or implying relative importance. These terms are only used to distinguish one type of information from another type of information. For example, without departing from the scope of the present disclosure, the first information can also be referred to as the second information, and similarly, the second information can also be referred to as the first information.

[0032] The present application will be further described in detail below by specific embodiments and in conjunction with the accompanying drawings.

[0033] The present application provides a method for reducing the grease injection amount of a ship propeller cap, which specifically comprises the following steps:

[0034] S1, according to the size and position relationship of the stern shaft 7 and the propeller cap 8, the size of the round cover is designed.

[0035] The round cover 4 comprises a cover plate 41 and a round pipe 42, the diameter of the cover plate 41 is not less than the outer diameter of the round pipe 42, the inner diameter of the round pipe 42 is greater than the thread diameter of the tail of the stern shaft 7 and less than the outer diameter of the hydraulic nut 9, and the length of the round pipe 42 is greater than the designed distance from the rear end surface of the stern shaft 7 to the hydraulic nut 9. The cover plate 41 is provided with bolt holes 43 for fixing it on the stern shaft 7, and the two bolt holes 43 are symmetrically arranged. In this embodiment, the cover plate 41 is a circular plate, and the round pipe 42 is a market product.

[0036] S2, according to the size of the propeller cap 8 and the round cover 4, the position of the fixed protrusion 1 to be newly added on the inner wall of the propeller cap is designed.

[0037] Let the distance from the fixed protrusion 1 to the front end surface of the propeller cap 8 be L, then L=L1+L2+δ+L3, L1 is the length of the hydraulic nut 9, L2 is the length of the round pipe 42, δ is the thickness of the cover plate 41, and L3 is the gap between the baffle 2 and the cover plate 41 after the propeller cap is installed.

[0038] S3, when casting the propeller cap 8, according to the design position of the fixed protrusion 1, an annular fixed protrusion 1 is extended out at the corresponding position on the inner wall of the propeller cap 8, and the fixed protrusion 1 is integrally injection molded with the original structure of the propeller cap 8.

[0039] A plurality of bolt holes are formed in the circumferential direction of the fixed protrusion 1.

[0040] S4, making a round cover 4 according to the designed round cover size.

[0041] S5, install the hydraulic nut 9 on the tail shaft 7. After the hydraulic nut 9 is installed, use the second bolt 5 and the third bolt 6 to fix the round cover 4 on the tail end face of the tail shaft 7 and make the end of the round tube 42 of the round cover 4 rest against the hydraulic nut 9.

[0042] S6, fix the baffle 2 on the fixing protrusion 1 extending from the inner wall of the propeller cap 8. After the baffle 2 is fixed, install the propeller cap 8 on the propeller 10. At this time, the baffle 2 divides the internal space of the propeller cap 8 into a first space 11 and a second space 12.

[0043] After the propeller cap 8 is installed on the propeller 10 , the gap between the baffle 2 and the round cover 4 is at least 30 mm, which can prevent the second bolt 5 and the third bolt 6 from contacting the baffle 2 .

[0044] The baffle 2 is a circular plate with a diameter greater than the outer diameter of the hydraulic nut 9. A plurality of bolt holes are provided along the circumference of the baffle 2. The number and position of the bolt holes on the baffle 2 correspond to the number and position of the bolt holes on the fixing boss 1. The baffle 2 is secured to the fixing boss 1 by first bolts 3, thereby dividing the interior space of the propeller cap 8 into a first space 11 and a second space 12. The tail end of the tail shaft 7 and the hydraulic nut 9 secured thereto are both located within the second space 12.

[0045] In this embodiment, the baffle 2 is a 5 mm thick steel sheet.

[0046] S7 , detecting the air tightness of the second space 12 inside the propeller cap 8 . If the air tightness meets the requirements, injecting grease into the second space 12 .

[0047] Specifically, when testing the air tightness of the second space 12 inside the propeller cap 8, the air pressure testing device is connected to the oil filling port of the propeller cap 8 through the air pipe, and then the air pump of the air pressure testing device is turned on to evacuate the second space 12. When the pressure displayed on the pressure gauge of the air pressure testing device reaches the set value, the air pumping is stopped. After maintaining the pressure for a certain period of time, it is judged whether the air tightness of the second space 12 is qualified according to the pressure value displayed on the pressure gauge.

[0048] Preferably, step S5 and step S6 can be performed simultaneously.

[0049] The application changes the structure of the propeller cap, adds a fixed protrusion integrally on the inner wall of the propeller cap, installs a baffle on the fixed protrusion, divides the internal space of the propeller cap into two parts by the baffle, reduces the oil injection space, thereby reducing the amount of grease used, and since only part of the space inside the propeller cap is injected with oil, the workload of cleaning the grease inside the propeller cap during disassembly and maintenance of the propeller cap is greatly reduced.

[0050] Meanwhile, by fixing the round cover 4 at the tail end of the tail shaft, since the inner diameter of the round pipe 42 of the round cover 4 is larger than the thread diameter of the tail end of the tail shaft 7 and smaller than the outer diameter of the hydraulic nut 9, after the round cover 4 is fixed with the tail shaft, a small part of space is included in the round pipe 42, which can further reduce the amount of grease used, and also prevent the grease from directly contacting the thread of the tail end of the tail shaft 7, and since the end of the round pipe 42 of the round cover 4 abuts against the hydraulic nut 9 after being fixed, it can prevent the hydraulic nut from loosening.

[0051] The application also provides a device for reducing the amount of grease injected into the propeller cap of a ship, which comprises a baffle 2 and a round cover 4, the inner wall of the propeller cap 8 extends a ring-shaped fixed protrusion 1, the baffle 2 is fixed on the fixed protrusion 1 by a plurality of first bolts 3 uniformly distributed in the circumferential direction, the round cover 4 is fixed on the tail shaft 7 by a second bolt 5 and a third bolt 6, and the round cover 4 abuts against the hydraulic nut 9, and a gap of at least 30 mm is maintained between the baffle 2 and the round cover 4.

[0052] The specific structure of the baffle 2 and the round cover 4 is as described above, and will not be described in detail here.

[0053] It should be clear that the described embodiments are only some of the embodiments of the application, not all. Based on the embodiments in the application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the application.

Claims

1. A method for reducing the amount of grease injected into a ship propeller cap, characterized in that: The specific steps include: S1, design the size of the round cover according to the size and position relationship of the tail shaft (7) and the propeller cap (8); S2, designing the position of the fixing protrusion (1) to be added to the inner wall of the propeller cap according to the dimensions of the propeller cap (8) and the round cover (4); S3, when casting the propeller cap (8), according to the design position of the fixing protrusion (1), an annular fixing protrusion (1) is extended from the corresponding position of the inner wall of the propeller cap (8), and the fixing protrusion (1) and the original structure of the propeller cap (8) are integrally injection molded; S4, making a round cover (4) according to the designed round cover size; The circular cover (4) includes a cover plate (41) and a circular tube (42). The cover plate (41) is provided with a bolt hole (43) for fixing the cover plate to the tail shaft (7) through a second bolt (5) and a third bolt (6). The diameter of the cover plate (41) is not less than the outer diameter of the circular tube (42). The inner diameter of the circular tube (42) is greater than the thread diameter of the tail of the tail shaft (7) and smaller than the outer diameter of the hydraulic nut (9). The length of the circular tube (42) is greater than the designed distance from the rear end face of the tail shaft (7) to the hydraulic nut (9). S5, install the hydraulic nut (9) on the tail shaft (7). After the hydraulic nut (9) is installed, fix the round cover (4) on the tail end surface of the tail shaft (7) and make the round cover (4) press against the hydraulic nut (9); S6, fixing the baffle (2) on the fixing protrusion (1) extending from the inner wall of the propeller cap (8), after the baffle (2) is fixed, installing the propeller cap (8) on the propeller (10), at this time, the baffle (2) divides the internal space of the propeller cap (8) into a first space (11) and a second space (12); S7, detecting the air tightness of the second space (12) inside the propeller cap (8), and injecting grease into the second space (12) after the air tightness meets the requirements.

2. The method for reducing the amount of grease injected into a ship propeller cap according to claim 1, characterized in that: After the propeller cap (8) is mounted on the propeller (10) in step S6, the gap between the baffle (2) and the round cover (4) is at least 30 mm.

3. The method for reducing the amount of grease injected into a ship propeller cap according to claim 2, characterized in that: The baffle (2) is fixed to the fixing protrusion (1) by a plurality of first bolts (3) evenly distributed in the circumferential direction.

4. The method for reducing the amount of grease injected into a ship propeller cap according to claim 1, characterized in that: When the air tightness of the second space (12) inside the propeller cap (8) is detected in step S7, the air pressure test device is connected to the oil filling port of the propeller cap (8) through the air pipe, and then the air pump of the air pressure test device is turned on to evacuate the second space (12). When the pressure displayed on the pressure gauge of the air pressure test device reaches the set value, the air pumping is stopped. After the pressure is maintained for a certain period of time, it is judged whether the air tightness of the second space (12) is qualified based on the pressure value displayed on the pressure gauge.

5. The method for reducing the amount of grease injected into a ship propeller cap according to claim 1, characterized in that: The diameter of the baffle (2) is larger than the outer diameter of the hydraulic nut (9).

6. The method for reducing the amount of grease injected into a ship propeller cap according to claim 1, characterized in that: Step S5 and step S6 can be performed simultaneously.

7. A device for reducing the amount of grease injected into a ship propeller cap, installed using the method according to any one of claims 1 to 6, characterized in that: The invention comprises a baffle (2) and a round cover (4), an annular fixing protrusion (1) extending from the inner wall of the propeller cap (8), the baffle (2) being fixed on the fixing protrusion (1) by a plurality of first bolts (3) evenly distributed in the circumferential direction, the round cover (4) being fixed on the tail shaft (7) by a second bolt (5) and a third bolt (6), and the round cover (4) being pressed against the hydraulic nut (9), and a gap of at least 30 mm being maintained between the baffle (2) and the round cover (4).

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