Device for chrome plating of oil ring surface

Abstract

The present invention discloses a device for chrome plating on the surface of an oil ring, comprising a core rod, a heat expansion tube which expands due to heat during the chrome plating process is sleeved on the outer circumference of the core rod, and an oil ring is sleeved on the outer circumference of the heat expansion tube. After the heat expansion tube expands due to heat, it is pressed against the inner wall of the oil ring to prevent the plating solution from flowing in the oil hole of the oil ring. The present invention can seal the oil holes on multiple oil rings at one time by sleeved a heat expansion tube on the core rod, thereby blocking the flow of the plating solution in the oil holes. Compared with the prior art in which a rubber ring is arranged in the oil hole of each oil ring, the cost and operation difficulty are greatly reduced. It takes about 10 minutes to install rubber rings on all the oil holes on each oil ring of the prior art, while it only takes about 2 minutes to install the heat expansion tube in the present invention.

Description

Technical Field

[0001] The invention relates to a device for electroplating on a workpiece, in particular to a device for chrome plating on the surface of an oil ring. Background Art

[0002] At present, there are two main types of chrome-plated piston rings, one is cast iron chrome-plated oil rings, and the other is steel chrome-plated oil rings. Whether it is cast iron or steel oil rings, a certain thickness of chrome layer is plated on its surface to increase its wear resistance. At present, the raw material of steel oil rings is purchased profiles, which have oil scraping strips, spring grooves and oil holes, etc., so in the manufacturing process, it is not necessary to reprocess the oil scraping strips, spring grooves and oil holes like cast iron oil rings. However, since the profile itself has oil holes, during electroplating, the plating liquid flows inside and outside the oil holes, resulting in the inability to plate the chrome layer at the oil holes. Therefore, the color of the oil holes is gray-black, and such oil holes are also called "panda eyes". This "panda eyes" seriously affects the appearance quality of the oil rings, especially the foreign trade rings have high requirements for the appearance quality of the rings, and currently the chrome-plated steel oil rings are mainly foreign trade rings.

[0003] The existing solution is to install rubber rings in the oil holes on the oil ring. Although it can prevent the plating solution from entering the oil holes to a certain extent, a rubber ring must be installed in each oil hole on the oil ring, which is cumbersome, inefficient, and costly, and is not conducive to large-scale production. Summary of the invention

[0004] Purpose of the invention: The purpose of the present invention is to provide a low-cost, easy-to-operate device for chrome plating on the surface of an oil ring.

[0005] Technical solution: The device for chrome plating the surface of an oil ring described in the present invention includes a core rod, the outer periphery of which is sleeved with a heat expansion tube that expands due to heat during the chrome plating process, and the oil ring is sleeved on the outer periphery of the heat expansion tube. After the heat expansion tube expands due to heat, it is pressed against the inner wall of the oil ring to prevent the plating solution from flowing in the oil hole of the oil ring.

[0006] Preferably, a gap is left between the outer wall of the thermal expansion cylinder and the inner wall of the oil ring.

[0007] Preferably, the outer diameter of the thermal expansion tube is determined according to the expansion coefficient of the thermal expansion tube and the outer diameter and radial thickness of the oil ring.

[0008] Preferably, the radial expansion amount of the thermal expansion tube is determined according to the outer diameter of the thermal expansion tube, the expansion coefficient of the thermal expansion tube, the plating solution temperature, and the temperature corresponding to the expansion coefficient of the thermal expansion tube.

[0009] Preferably, one or more oil rings are sleeved on the outer circumference of the thermal expansion cylinder.

[0010] The length of the thermal expansion tube is at least the same as the thickness of the oil ring sleeved on the thermal expansion tube.

[0011] Preferably, the material of the heat expansion tube is a thermoplastic resin material; the material of the heat expansion tube is an anti-corrosion material. More preferably, the heat expansion tube is a nylon tube.

[0012] Preferably, the expansion coefficient of the thermal expansion tube is 14-16×10 -5 .

[0013] Beneficial effects: Compared with the prior art, the present invention has achieved the following significant effects: 1. A heat expansion tube is sleeved on the core rod to seal the oil holes on multiple oil rings at one time, blocking the flow of electroplating liquid in the oil holes. Compared with the prior art in which a rubber ring is set in the oil hole of each oil ring, the cost and operation difficulty are greatly reduced; 2. The heat expansion tube is an elastic tube, which has a better blocking effect than a non-elastic tube. 3. The heat expansion tube can be recycled, further reducing costs; 4. It is not subject to strict matching restrictions on the aperture size on the oil ring, and the length of the heat expansion tube only needs to be greater than or equal to the total thickness of the oil ring sleeved on the heat expansion tube. 5. It is only necessary to make the specific size of the heat expansion tube according to the size of the oil ring and the expansion properties of the heat expansion tube, and then sleeve the heat expansion tube on the outer periphery of the core rod, which has high production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the structure of the device of the present invention;

[0015] Figure 2 It is a partial enlarged structural schematic diagram of the oil ring and the thermal expansion tube;

[0016] Figure 3 It is a schematic diagram of the structure of the thermal expansion tube;

[0017] Figure 4 This is a schematic diagram of the structure of the thermal expansion tube after chrome plating;

[0018] Figure 5 Schematic diagram of the structure of the oil ring. DETAILED DESCRIPTION

[0019] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0020] like Figure 1-3As shown, the present invention discloses a device for chrome plating the surface of an oil ring 3, comprising a core rod 1, a heat expansion tube 2 which is thermally expanded during the chrome plating process is sleeved on the outer periphery of the core rod 1, and an oil ring 3 is sleeved on the outer periphery of the heat expansion tube 2. After the heat expansion, the heat expansion tube 2 is pressed against the inner wall of the oil ring 3 to prevent the plating solution from entering the hole on the wall of the oil ring 3. A gap is left between the outer wall of the heat expansion tube 2 and the inner wall of the oil ring 3. The outer diameter of the heat expansion tube 2 is determined according to the expansion coefficient of the heat expansion tube 2, the outer diameter of the oil ring 3, and the radial thickness of the oil ring 3. The radial expansion amount of the heat expansion tube 2 is determined according to the outer diameter of the heat expansion tube 2, the expansion coefficient of the heat expansion tube 2, the plating solution temperature, and the temperature corresponding to the expansion coefficient of the heat expansion tube 2. Multiple oil rings 3 can be sleeved on the outer periphery of the heat expansion tube 2 at the same time. The length of the heat expansion tube 2 is at least the same as the thickness of the oil ring 3 sleeved on the heat expansion tube 2. The heat expansion tube 2 of this embodiment is a nylon tube, and the material of the heat expansion tube 2 can also be other thermoplastic resin materials, and is preferably an anti-corrosion material. The expansion coefficient of the thermal expansion tube 2 is 14-16×10 -5 The upper and lower ends of the core rod 1 are provided with pressure plates 4 for pressing the oil ring 3 , and the upper and lower pressure plates 4 are locked with locking nuts 5 .

[0021] Working process: The method for chrome plating the oil ring using the above device includes the following steps:

[0022] (1) Take the chrome-plated steel oil ring 3 from foreign trade, the cylinder diameter is The radial thickness of the ring is 3.0, and the inner diameter of the oil ring 3 after clamping is: D inner diameter = 139.7-3.0×2 = 133.7;

[0023] The calculation formula of the inner diameter of the oil ring D is: D inner diameter = D outer - 2*T

[0024] like Figure 5 As shown, D is the outer diameter of the oil ring, which is determined by the cylinder diameter of the engine used and is equivalent to the cylinder diameter of the engine, and T is the radial thickness of the oil ring;

[0025] (2) Preparation of nylon tubes, the expansion coefficient of nylon is 14-16×10 -5 , take the middle value as 0.00015. Since the inner diameter of the oil ring 3 is Therefore, the radial expansion of the nylon tube in the 60°C chrome plating solution is: 133.7×0.00015×(60-20)=0.8022, so the actual outer diameter of the nylon tube 2 is designed to be: 133.7-0.8022+0.10=132.99, and the +0.10 in the calculation is to facilitate the nylon tube to expand and fit the inner diameter of the ring to better seal the oil hole;

[0026] The calculation formula of the radial expansion of the nylon tube is: (Douter-2*T)×0.00015×(60-20)

[0027] 60 is the temperature of the chrome plating solution, and 20 is the temperature when the nylon expansion coefficient is 0.00015;

[0028] (3) processing the nylon tube 2 according to the actual outer diameter of the nylon tube 2 calculated in step (2), first mounting the nylon tube 2 on the chrome-plated core rod 1, then mounting the oil ring 3 to be chrome-plated on the outer diameter of the nylon tube 2, and finally closing the oil ring, pressing the oil ring with a pressing plate 4, and locking it with a locking nut 5; placing the chrome-plated core rod 1 with the oil ring 3 mounted thereon into a plating solution at 60°C±2°C for electroplating;

[0029] (4) After the electroplating is completed, the oil ring 3 and the nylon tube 2 are taken out. The surface of the nylon tube 2 is as follows Figure 4 shown.

[0030] from Figure 4 It can be seen that the surface of the nylon tube 2 has traces of contact with the inner surface of the oil ring 3, indicating that the nylon tube 2 seals the oil hole on the oil ring 3, preventing the plating solution from entering the oil hole on the oil ring 3 and preventing the plating solution from flowing through the oil hole of the oil ring 3. This avoids the formation of "panda eyes" on the oil ring. In addition, the cost of using a nylon tube in this embodiment is only about 20 yuan, and the cost of installing a tube ring with an O-type rubber ring is about 500 yuan, which greatly reduces the cost.

Claims

1. A device for chrome plating the surface of an oil ring, comprising a core rod (1), characterized in that: The outer circumference of the core rod (1) is sleeved with a heat expansion tube (2) that expands due to heat during the chrome plating process, and the oil ring (3) is sleeved on the outer circumference of the heat expansion tube (2). After the heat expansion, the heat expansion tube (2) is pressed against the inner wall of the oil ring (3) to prevent the plating solution from flowing in the oil hole of the oil ring (3).

2. The device for chrome plating the surface of an oil ring according to claim 1, characterized in that: A gap is left between the outer wall of the thermal expansion cylinder (2) and the inner wall of the oil ring (3).

3. The device for chrome plating the surface of an oil ring according to claim 1, characterized in that: The outer diameter of the thermal expansion tube (2) is determined according to the expansion coefficient of the thermal expansion tube (2), the outer diameter of the oil ring (3), and the radial thickness of the oil ring (3).

4. The device for chrome plating the surface of an oil ring according to claim 1, characterized in that: The radial expansion amount of the thermal expansion tube (2) is determined according to the outer diameter of the thermal expansion tube (2), the expansion coefficient of the thermal expansion tube (2), the plating solution temperature, and the temperature corresponding to the expansion coefficient of the thermal expansion tube (2).

5. The device for chrome plating the surface of an oil ring according to claim 1, characterized in that: The length of the thermal expansion tube (2) is at least the same as the thickness of the oil ring (3) sleeved on the thermal expansion tube (2).

6. The device for chrome plating the surface of an oil ring according to claim 1, characterized in that: One or more oil rings (3) are sleeved on the outer circumference of the thermal expansion cylinder (2).

7. The device for chrome plating the surface of an oil ring according to claim 1, characterized in that: The material of the thermal expansion cylinder (2) is a thermoplastic resin material.

8. The device for chrome plating the surface of an oil ring according to claim 1, characterized in that: The material of the thermal expansion tube (2) is corrosion-resistant material.

9. The device for chrome plating the surface of an oil ring according to claim 1, characterized in that: The thermal expansion tube (2) is a thermal expansion elastic tube, and the thermal expansion elastic tube is a nylon tube.

10. The device for chrome plating the surface of an oil ring according to claim 1, characterized in that: The expansion coefficient of the thermal expansion tube (2) is 14-16×10 -5 .

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