Cylinder liner centrifugally cast gate ring

Abstract

The utility model discloses a cylinder liner centrifugal casting door circle belongs to internal combustion engine parts manufacturing technical field. The door circle mainly includes hollow stainless steel door circle, heat preservation material, apron and heat preservation coating. Hollow stainless steel door circle one side end face is equipped with annular groove, and the groove is filled with glass fiber felt as heat preservation material, and is sealed by a steel apron welding, forms the heat -insulating cavity. The other side end face on the door circle has the heat preservation coating that sprays with diatomite as the aggregate. The utility model discloses through adopting low heat conductivity's stainless steel material, thinning wall thickness, inside filling heat preservation material and the composite heat -insulating structure that outside sprays heat preservation coating, has reduced the cooling speed of molten iron at the end of mould greatly to guarantee that the cylinder liner blank big head does not produce white structure, cancels the use of disposable heat preservation pad completely simultaneously, effectively reduces production cost.

Description

Technical Field

[0001] This utility model relates to the field of internal combustion engine parts manufacturing technology, and in particular to a cylinder liner centrifugal casting door ring. Background Technology

[0002] Cylinder liners are core components of internal combustion engines. Their blanks are generally produced using a metal mold centrifugal casting process, with alloy cast iron being the most common material. In this process, to prevent harmful white cast iron structures from forming on the large end face of the cylinder liner blank, the traditional method is to place thermal insulation pads at both ends of the centrifugal casting mold. These thermal insulation pads are for single use only, resulting in high consumption and consequently high production costs.

[0003] To reduce production costs, existing technologies employ a process using solid cast iron door liners coated with insulating paint to replace disposable insulation pads. However, due to the high thermal conductivity of ordinary cast iron, its solid, integral structure dissipates heat quickly, resulting in limited insulation. In actual production, it remains difficult to completely prevent white cast iron formation at the large end of the cylinder liner, affecting the stability and consistency of product quality.

[0004] Therefore, there is an urgent need for a new type of centrifugally cast cylinder liner structure that can effectively solve the above problems, eliminating the need for disposable insulation pads while ensuring the quality of cylinder liner blanks. Utility Model Content

[0005] The purpose of this utility model is to provide a cylinder liner centrifugal casting door ring, which aims to improve heat insulation performance, ensure that no white iron structure is generated in the large end of the cylinder liner centrifugal casting blank, thereby eliminating the use of disposable heat insulation pads, achieving the goal of reducing production costs and ensuring product quality.

[0006] This utility model is achieved using the following technical solution: a cylinder liner centrifugally cast door ring, characterized in that it includes a door ring, insulation material, a cover plate, and an insulation coating; one end face of the hollow stainless steel door ring is provided with an annular groove, and the insulation material is filled in the annular groove; the cover plate is sealed and fixedly connected to the end face provided with the annular groove, encapsulating the insulation material in the cavity formed by the door ring and the cover plate; the insulation coating is sprayed on the other end face of the hollow stainless steel door ring.

[0007] Furthermore, the door frame is made of 304 stainless steel.

[0008] Furthermore, the wall thickness of the door ring is 5-8 mm.

[0009] Furthermore, the insulation material is fiberglass felt.

[0010] Furthermore, the cover plate is made of steel plate and is fixedly connected to the door ring by welding.

[0011] Furthermore, the cover plate has a thickness of 3 millimeters.

[0012] Furthermore, the thermal insulation coating is a coating layer with diatomaceous earth as aggregate and a thickness of 200-400μm.

[0013] The beneficial effects of the centrifugally cast cylinder liner gate ring described in this utility model include: By employing a combination of technologies, including using stainless steel with low thermal conductivity, reducing the wall thickness of the cylinder liner, filling with internal insulation materials, and spraying with external insulation coatings, multiple thermal barriers are formed. This greatly slows down the solidification and cooling rate of molten iron at the large end of the cylinder liner, ensuring the full progress of the graphitization process. This effectively avoids the formation of white cast iron structure and guarantees the casting quality of the cylinder liner blank.

[0014] The door ring of this utility model is a reusable permanent mold component, which successfully replaces the disposable insulation pad in the traditional process, and the auxiliary material cost of a single cylinder liner is greatly reduced.

[0015] 304 stainless steel has good high-temperature strength and thermal fatigue resistance. The hollow filling structure enhances the overall stability, enabling it to withstand the high temperature and thermal shock during centrifugal casting. It is durable and has a long service life. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. The drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0017] Figure 1 A schematic diagram of a cylinder liner centrifugally cast valve ring; In the diagram, 1-door frame, 2-cover plate, 3-insulation material, 4-insulation coating. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0019] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention. Example

[0020] like Figure 1 As shown, this embodiment provides a cylinder liner centrifugal casting door ring, which consists of a hollow stainless steel door ring 1, a cover plate 2, a thermal insulation material 3, and a thermal insulation coating 4.

[0021] The hollow stainless steel door ring 1 is made of 304 stainless steel with a wall thickness of 5-8 mm (the specific value is determined according to the size of the cast cylinder liner blank; the larger the cylinder liner blank, the thicker the wall thickness). An annular groove is machined on one end face of the door ring 1, and the groove is tightly filled with insulation material 3, which is made of fiberglass felt. The cover plate 2 is made of ordinary low-carbon steel plate with a thickness of 3 mm. It is continuously welded to the grooved end face of the hollow stainless steel door ring 1 to form a sealed whole, thus completely encapsulating the insulation material 3 within the sealed cavity formed by the door ring 1 and the cover plate 2.

[0022] On the other end face of the door ring 1, a thermal insulation coating 4 with diatomaceous earth as aggregate is sprayed. The spraying process requires that the hollow stainless steel door ring be preheated to 200–300℃, and then the thermal insulation coating is evenly sprayed onto the end face using spraying equipment to form a thermal insulation coating 4 with a thickness of 200–400μm.

[0023] The prepared door ring with the heat-insulating coating 4 on its surface is placed on the end face of the cylinder liner centrifugal casting mold. Then, the centrifugal casting machine is started to pour high-temperature molten iron into the mold cavity. The molten iron fills and solidifies under the action of centrifugal force. Due to the heat insulation effect of the door ring, a cylinder liner blank without white cast iron structure at the large end can be obtained.

[0024] Its working principle is explained in detail below: When molten iron comes into contact with the gate ring 1 after being poured, the heat transfer process is hindered by multiple factors. First, the outermost insulating coating 4 has low thermal conductivity and high thermal resistance, effectively reducing the initial thermal shock. Second, the gate ring 1 body is made of 304 stainless steel, and its wall thickness is significantly reduced to 5-8 mm. This allows the gate ring 1 body to reach thermal saturation more quickly during the casting process, increasing the overall temperature and thus reducing the temperature difference between it and the molten iron, thereby slowing down the cooling rate. Finally, the glass fiber felt insulation material 3 filling the internal cavity further improves the overall thermal insulation performance of the structure, greatly delaying the loss of heat to the mold end.

[0025] Through the synergistic effect of the above-mentioned triple heat preservation mechanism, the solidification and cooling rate of molten iron at the large end of the cylinder liner is significantly reduced, allowing the molten iron in this area to remain under a higher temperature gradient for a longer period of time, thereby avoiding cementite precipitation, ensuring that the graphitization process proceeds fully, and ultimately effectively inhibiting the formation of white iron structure.

[0026] The core innovation of this technical solution lies in the complete elimination of disposable insulation pads through a combination of material replacement, lightweight structure, and thermal insulation design. This significantly reduces production costs while ensuring the quality of cylinder liner blanks, and at the same time improves process stability and product consistency.

[0027] The above embodiments describe the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Modifications and variations made by those skilled in the art without departing from the spirit and scope of this utility model should be protected within the scope of the appended claims.

Claims

1. A cylinder liner centrifugally cast valve ring, characterized in that, It includes a door ring (1), insulation material (3), cover plate (2) and insulation coating (4); one end face of the door ring (1) is provided with an annular groove, and the insulation material (3) is filled in the annular groove; the cover plate (2) is sealed and fixedly connected to the end face provided with the annular groove, and the insulation material (3) is encapsulated in the cavity formed by the door ring (1) and the cover plate (2); the insulation coating (4) is sprayed on the other end face of the door ring (1).

2. The cylinder liner centrifugal casting valve ring according to claim 1, characterized in that, The door ring (1) is made of 304 stainless steel.

3. The cylinder liner centrifugal casting gate ring according to claim 1, characterized in that, The wall thickness of the door ring (1) is 5-8 mm.

4. A cylinder liner centrifugally cast valve ring according to claim 1, characterized in that, The insulation material (3) is fiberglass felt.

5. A cylinder liner centrifugally cast valve ring according to claim 1, characterized in that, The cover plate (2) is a steel plate, which is fixedly connected to the door ring (1) by welding.

6. A cylinder liner centrifugally cast valve ring according to claim 1, characterized in that, The cover plate (2) is 3 mm thick.

7. A cylinder liner centrifugally cast valve ring according to claim 1, characterized in that, The thermal insulation coating (4) is a coating layer with diatomaceous earth as aggregate and a thickness of 200-400μm.

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