Sleeve core type circulating water cooling tool for inner hole of cylinder sleeve of large marine diesel engine
By installing a circulating water cooling pipe inside the cylinder liner core tube, the problem of low cooling efficiency of the cylinder liner inner bore in marine diesel engines is solved by utilizing circulating water cooling technology, achieving efficient and continuous cooling effect and improved wear resistance.
Patent Information
- Application Number
- CN202520419543.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-11
- Publication Date
- 2026-02-03
- Estimated Expiration
- 2035-03-11
AI Technical Summary
Existing technologies for cooling the inner bore of marine diesel engine cylinder liners suffer from problems such as high labor intensity, insignificant or unsustainable cooling effect, easy stress generation, and complex preliminary preparation work.
A core-type circulating water cooling fixture is adopted. By setting a circulating water cooling pipe inside the cylinder liner core tube, the circulating water continuously removes the heat of the cylinder liner inner hole in the cast state, thereby continuously accelerating the cooling rate and ensuring the fine structure of the inner hole and the surface strength.
It achieves efficient and continuous cooling of the cylinder liner inner bore, reduces the labor intensity of workers, improves the wear resistance and strength of the inner bore, eliminates the need for post-stress relief heat treatment, and significantly improves the surface hardness and strength of the inner bore.
Smart Images
Figure CN223862823U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of marine diesel engine cylinder liner casting technology, and mainly to a large marine diesel engine cylinder liner inner hole core-type circulating water cooling tooling. Background Technology
[0002] Marine low-speed diesel engine cylinder liners are usually made of gray cast iron alloy material. The inner surface of the cylinder liner and its running piston form a complete friction pair. Since the inner surface of the cylinder liner is in direct contact with combustion and explosion, the working environment is harsh. Therefore, high requirements are placed on the wear resistance and strength of the inner surface of the cylinder liner. In particular, the inner surface of the cylinder liner is required to have high strength and fine structure.
[0003] To meet the special requirements of the cylinder liner inner bore, accelerating the cooling rate of the as-cast cylinder liner inner bore during the casting process is crucial. A common approach is to apply chills to the surface of the cylinder liner inner bore to accelerate cooling. However, this method is labor-intensive and relies entirely on manual labor. Furthermore, chills have limited heat storage capacity and are easily saturated, failing to provide sustained cooling, especially for thick-walled cylinder liners. While spray cooling offers significant cooling effects, the reaction is too intense and can easily create stress, requiring subsequent heat treatment to relieve this stress. Additionally, each cylinder liner model requires pre-calculation of its solidification time, followed by core removal before implementing spray cooling. This process involves extensive preparation and is not particularly convenient. Utility Model Content
[0004] To address the aforementioned technical problems, the purpose of this utility model is to provide a circulating water cooling fixture for the inner bore of a large marine diesel engine cylinder liner. This fixture involves inserting a core tube with circulating water inside the cylinder liner core tube. The circulating water continuously removes heat from the inner bore of the cylinder liner in its as-cast state, allowing for continuous heat dissipation and cooling. This achieves the goal of continuously accelerating the cooling rate of the inner bore of the cylinder liner, thereby ensuring a fine internal structure, high inner surface strength, and ultimately improving the wear resistance of the working surface of the inner bore. Furthermore, the fixture is simple and efficient to operate and can continuously accelerate the cooling rate of the inner bore of the diesel engine cylinder liner in its as-cast state.
[0005] To achieve the above-mentioned technical features, the purpose of this utility model is as follows: a circulating water cooling fixture with an inner core for the cylinder liner of a large marine diesel engine, including a circulating water cooling pipe, the bottom end of which is sealed by a base plate, an inner water supply pipe fixed on the inner wall of the circulating water cooling pipe, the top end of which extends out of the circulating water cooling pipe and is bent to form an inlet pipe, the bottom end of which is set at the inner bottom of the circulating water cooling pipe and is bent to form an arc-shaped outlet pipe, an outlet is machined on the upper part of the circulating water cooling pipe, and an outlet pipe is fixed at the location of the outlet.
[0006] Preferably, the circulating water cooling pipe is made of seamless steel pipe, and a waist-shaped hole for hoisting is provided at the upper part of the circulating water cooling pipe.
[0007] Preferably, the base plate is sealed and welded to the bottom end of the circulating water cooling pipe through a base plate weld point.
[0008] Preferably, the internal water supply pipe is welded and fixed to the inner wall of the circulating water cooling pipe through a first weld point and a second weld point.
[0009] Preferably, the outlet of the arc-shaped water outlet pipe faces the top of the circulating water cooling pipe.
[0010] Preferably, the inlet pipe is connected to a water tower and introduces cold water, and the outlet pipe is connected to a water tower or a bathhouse water storage tank.
[0011] Preferably, the entire circulating water cooling pipe is located at the center of the cylinder liner core tube, and core tube molding sand is provided on the outer wall of the cylinder liner core tube. The core tube molding sand is in contact with the inner hole of the cast cylinder liner, and the outer wall of the cast cylinder liner is in contact with the cylinder liner molding sand. The cylinder liner molding sand is located inside the cylinder liner casting sand box.
[0012] Preferably, an external chill is provided between the middle outer wall of the cast cylinder liner and the cylinder liner molding sand.
[0013] The present invention has the following beneficial effects:
[0014] 1. By adopting this utility model, the circulating water can continuously remove the heat from the inner hole of the cylinder liner in the casting state, allowing the inner hole to dissipate heat first, thereby continuously accelerating the cooling speed of the inner hole of the cylinder liner. This ensures the fineness of the inner hole structure and the high strength of the inner surface, thereby improving the wear resistance of the inner hole surface. At the same time, the hot water is led to the bathhouse water tower, which can be used for the casting employees to take a bath, thus realizing part of the heat energy recovery.
[0015] 2. By adopting this utility model, in the production process of a certain type of thick-walled low-speed diesel engine cylinder liner casting, the above-mentioned internal circulating water cooling method not only significantly reduces the labor intensity of workers and allows for continuous and accelerated cooling of the cylinder liner inner bore in the as-cast state, but also minimizes the stress in the cylinder liner inner bore, eliminating the need for subsequent stress-relieving heat treatment. Metallographic testing shows that the microstructure of the cylinder liner inner bore is significantly refined, the strength is increased by 20-40 MPa, and the surface hardness of the inner bore is increased by 30-40 HB, thereby improving the mechanical properties and wear resistance of the inner bore surface of the marine low-speed diesel engine cylinder liner. Attached Figure Description
[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0017] Figure 1 This is a structural diagram of the tooling of this utility model.
[0018] Figure 2 For the present utility model Figure 1 Enlarged view of the location of the central water inlet pipe.
[0019] Figure 3 For the present utility model Figure 1 Enlarged view of the location of the arc-shaped water outlet pipe.
[0020] Figure 4 This is a diagram showing the tooling installation layout for the casting process of this utility model.
[0021] In the diagram: 1. Inlet pipe; 2. First weld point; 3. Inner water supply pipe; 4. Waist-shaped hole; 5. Outlet; 6. Circulating water cooling pipe; 7. Second weld point; 8. Arc-shaped outlet pipe; 9. Base plate; 10. Base plate weld point; 11. Surface of cast cylinder liner inner bore; 12. Cylinder liner casting sand box; 13. Core tube molding sand; 14. Cylinder liner molding sand; 15. Outer chill; 16. Cast cylinder liner; 17. Detailed Implementation
[0022] The embodiments of this utility model will be further described below with reference to the accompanying drawings.
[0023] Example 1:
[0024] See Figure 1-4 A large marine diesel engine cylinder liner inner bore core-type circulating water cooling fixture includes a circulating water cooling pipe 7. The bottom end of the circulating water cooling pipe 7 is sealed by a base plate 10. An inner water supply pipe 3 is fixed on the inner wall of the circulating water cooling pipe 7. The top end of the inner water supply pipe 3 extends out of the circulating water cooling pipe 7 and is bent to form an inlet pipe 1. The bottom end of the inner water supply pipe 3 is set at the inner bottom of the circulating water cooling pipe 7 and is bent to form an arc-shaped outlet pipe 9. An outlet 5 is machined on the upper part of the circulating water cooling pipe 7. An outlet pipe 6 is fixed at the location of the outlet 5. This tooling involves inserting a core tube with circulating water inside the cylinder liner core tube. The circulating water continuously removes heat from the inner bore of the cylinder liner in the as-cast state, allowing the inner bore to continuously dissipate heat and cool down. This achieves the purpose of continuously accelerating the cooling rate of the inner bore of the cylinder liner, thereby ensuring the fineness of the inner bore structure, high strength of the inner surface, and ultimately improving the wear resistance of the working surface of the inner bore of the cylinder liner. In addition, it is simple and efficient to operate and can continuously accelerate the cooling rate of the inner bore of the diesel engine cylinder liner in the as-cast state.
[0025] Furthermore, the circulating water cooling pipe 7 is made of seamless steel pipe, and a waist-shaped hole 4 for hoisting is provided at the upper part of the circulating water cooling pipe 7. The use of seamless steel pipe effectively prevents subsequent leakage problems. The waist-shaped hole 4 facilitates the subsequent hoisting and lowering of the entire circulating water cooling pipe 7, thereby facilitating the installation and arrangement of the entire tooling.
[0026] Furthermore, the base plate 10 is sealed and welded to the bottom end of the circulating water cooling pipe 7 via base plate weld points 11. The base plate 10 described above can be used to reliably seal the circulating water cooling pipe 7.
[0027] Furthermore, the internal water supply pipe 3 is welded and fixed to the inner wall of the circulating water cooling pipe 7 via a first weld point 2 and a second weld point 8. The first weld point 2 and the second weld point 8 described above can be used to reliably fix the internal water supply pipe 3.
[0028] Furthermore, the outlet of the arc-shaped water outlet pipe 9 faces the top of the circulating water cooling pipe 7. The arc-shaped water outlet pipe 9 can be used to guide the cold water entering the circulating water cooling pipe 7, thereby ensuring that the cold water is continuously sprayed upward.
[0029] Furthermore, the inlet pipe 1 is connected to a water tower and introduces cold water, while the outlet pipe 6 is connected to a water tower or a bathhouse water storage tank. The outlet pipe 6 facilitates the removal of heated water, thus achieving the effect of heat energy reuse.
[0030] Furthermore, the entire circulating water cooling pipe 7 is located at the center of the cylinder liner core tube 18. Core tube molding sand 14 is provided on the outer wall of the cylinder liner core tube 18, and the core tube molding sand 14 contacts the inner hole of the cast cylinder liner 17. The outer wall of the cast cylinder liner 17 contacts the cylinder liner molding sand 15, which is located inside the cylinder liner casting sand box 13. Through the above casting structure, effective casting of the inner cylinder liner can be achieved.
[0031] Furthermore, an external chill 16 is provided between the outer wall of the middle portion of the cast cylinder liner 17 and the cylinder liner molding sand 15. The external chill 16 can be used to achieve external cooling of the cast cylinder liner 17 during the casting process.
[0032] Example 2:
[0033] This utility model provides a casting method for a core-type circulating water cooling system for the inner bore of a large marine diesel engine cylinder liner. The casting method is implemented using the core-type circulating water cooling fixture and includes the following steps:
[0034] Step 1, bending and shaping the inner water supply pipe 3:
[0035] Select steel pipes of appropriate size and bend the ends to form inlet pipe 1 and arc-shaped outlet pipe 9 respectively;
[0036] Step 2, Assembly of internal water supply pipe 3:
[0037] Select a circulating water cooling pipe 7 of appropriate size, and fix the bent and shaped inner water supply pipe 3 inside the circulating water cooling pipe 7 by spot welding.
[0038] Step 3, sealing the bottom of the circulating water cooling pipe 7:
[0039] After the internal water supply pipe 3 is fixed, the bottom plate 10 is welded to the bottom end of the circulating water cooling pipe 7 for sealing.
[0040] Step 4, Installation of the core-type circulating water cooling fixture:
[0041] After the cast cylinder liner 17 is cast, the core-type circulating water cooling fixture is fitted inside the cylinder liner core tube 18 by hoisting the core as a whole, and is arranged coaxially.
[0042] Step 5, connecting the core-type circulating water cooling fixture:
[0043] Connect the inlet pipe 1 to the cold water pipe of the water tower to introduce cold water. The cold water is discharged from the arc-shaped outlet pipe 9 and flows into the circulating water cooling pipe 7. The water level inside the circulating water cooling pipe 7 rises to the position of the outlet pipe 6 and flows out from the outlet pipe 6. The outlet pipe 6 is connected to the cooling water tower and the bathhouse water storage tank. Hot water is used for employees to take showers.
[0044] Step 6, circulating cooling of the as-cast cylinder liner 17:
[0045] As the as-cast cylinder liner 17 solidifies and cools down from a liquid to a solid state, a large amount of heat is conducted to the cylinder liner core tube 18 through the core tube molding sand 14 and the cylinder liner molding sand 15, causing the cylinder liner core tube 18 to heat up rapidly until it turns red and reaches saturation. As the heat radiation inside the cylinder liner core tube 18 intensifies, it heats the water inside the circulating water cooling pipe 7. Due to the flow of the circulating water, heat is continuously carried away from the outlet pipe 6 in the form of hot water, thereby achieving a positive temperature gradient for heat conduction from the as-cast cylinder liner 17 to the circulating water. This continuously carries away the heat from the entire inner hole of the as-cast cylinder liner 17, thereby accelerating the cooling of the inner hole of the as-cast cylinder liner 17 and achieving continuous cooling of the inner hole surface of the cylinder liner. This ensures the inner hole strength and the density of the structure, thereby improving the wear resistance of the inner surface of the cylinder liner.
[0046] Step 7, Disassembly of the core-type circulating water cooling fixture:
[0047] After the casting of the as-cast cylinder liner 17 is completed, remove the circulating water cooling pipe 7 for future use.
[0048] Furthermore, by using circulating water cooling to accelerate cooling, the stress in the cylinder liner inner bore is reduced, eliminating the need for subsequent stress-relief heat treatment. Metallographic testing shows that the microstructure of the cylinder liner inner bore is significantly refined, the strength is increased by 20-40 MPa, and the surface hardness of the inner bore is increased by 30-40 HB.
Claims
1. A circulating water-cooling fixture for the inner bore of a large marine diesel engine cylinder liner, characterized in that, The system includes a circulating water cooling pipe (7), the bottom end of which is sealed by a base plate (10). An inner water supply pipe (3) is fixed on the inner wall of the circulating water cooling pipe (7). The top end of the inner water supply pipe (3) extends out of the circulating water cooling pipe (7) and is bent to form an inlet pipe (1). The bottom end of the inner water supply pipe (3) is set at the inner bottom of the circulating water cooling pipe (7) and is bent to form an arc-shaped outlet pipe (9). An outlet (5) is machined on the upper part of the circulating water cooling pipe (7), and an outlet pipe (6) is fixed at the location of the outlet (5).
2. The circulating water cooling fixture for the inner bore of the cylinder liner of a large marine diesel engine according to claim 1, characterized in that: The circulating water cooling pipe (7) is made of seamless steel pipe, and a waist-shaped hole (4) for hoisting is provided on the upper part of the circulating water cooling pipe (7).
3. The circulating water cooling fixture for the inner bore of the cylinder liner of a large marine diesel engine according to claim 1, characterized in that: The base plate (10) is sealed and welded to the bottom end of the circulating water cooling pipe (7) through the base plate welding point (11).
4. The circulating water cooling fixture for the inner bore of the cylinder liner of a large marine diesel engine according to claim 3, characterized in that: The internal water supply pipe (3) is welded and fixed to the inner wall of the circulating water cooling pipe (7) by the first welding point (2) and the second welding point (8).
5. The circulating water cooling fixture for the inner bore of the cylinder liner of a large marine diesel engine according to claim 1, characterized in that: The outlet of the arc-shaped water outlet pipe (9) faces the top of the circulating water cooling pipe (7).
6. The circulating water cooling fixture for the inner bore of the cylinder liner of a large marine diesel engine according to claim 1, characterized in that: The inlet pipe (1) is connected to the water tower and introduces cold water, and the outlet pipe (6) is connected to the water tower or the bathhouse water storage tank.
7. The circulating water cooling fixture for the inner bore of the cylinder liner of a large marine diesel engine according to claim 1, characterized in that: The entire circulating water cooling pipe (7) is located at the center of the cylinder liner core tube (18). Core tube molding sand (14) is provided on the outer wall of the cylinder liner core tube (18). Core tube molding sand (14) is in contact with the inner hole of the cast cylinder liner (17). The outer wall of the cast cylinder liner (17) is in contact with the cylinder liner molding sand (15). The cylinder liner molding sand (15) is located inside the cylinder liner casting sand box (13).
8. The circulating water cooling fixture for the inner bore of the cylinder liner of a large marine diesel engine according to claim 7, characterized in that: An external chill (16) is provided between the middle outer wall of the cast cylinder liner (17) and the cylinder liner molding sand (15).