High-precision accessory case transmission rod and heat treatment process thereof

Abstract

The application discloses a high-precision accessory gearbox transmission rod and a heat treatment process thereof. The accessory gearbox transmission rod comprises a rod body, a through hole is arranged on an axis of the rod body, and the rod body is provided with splines at both ends. The rod body and the splines are an integral structure, the outer diameter of the rod body is larger than that of the splines, the through hole penetrates the rod body and the splines, and the material of the gearbox transmission rod is 60Si2MnA. The heat treatment process of the high-precision accessory gearbox transmission rod comprises the following steps: step 1, clamping, the accessory gearbox is hung on a quenching clamp by using a nickel-chromium wire binding piece; step 2, quenching, a flow particle furnace is heated to 860±10 DEG C and kept for 15 min, then the accessory gearbox is loaded into the flow particle furnace, kept for 7-15 min, and then taken out and oil-cooled; step 3, oil removal, quenching oil stains are removed; and step 4, tempering, a common furnace is heated to 440±20 DEG C and kept for 15 min, then the accessory gearbox is loaded into the common furnace, kept for 60-80 min, and then taken out and water-cooled. The process uses a flow particle furnace for heating, graphite powder is used as a heating medium, and the inner hole of the transmission rod will not be blocked.

Description

Technical Field

[0001] This invention belongs to the field of spring steel quenching technology, specifically relating to a high-precision accessory housing transmission rod and its heat treatment process. Background Technology

[0002] During the development of a new type of aero-engine, the design drawings specify 60Si2MnA as the material, with a hardness requirement of HRC=46-51, and inspection according to HB5013-1996 Class III. 60Si2MnA is a widely used alloy spring steel with high hardenability but a significant tendency for decarburization. The accessory gearbox transmission rod is a special structure with through holes, requiring high dimensional accuracy. The design drawings demand high part hardness, necessitating that the splines at both ends of the part be machined to their final dimensions before heat treatment. The heat treatment must ensure a final hardness of HRC=46-51, with no deformation or oxidation / decarburization.

[0003] To control deformation and prevent oxidation and decarburization, traditional processes employ vacuum oil quenching within the hardness range specified in standard HB / Z136-2000. However, due to the slow quenching transfer speed (≥20 seconds) during vacuum oil quenching, the part temperature drops significantly, making it difficult to guarantee the required hardness. This often results in rework failures and scrapped parts. Currently, the industry uses salt bath heat treatment to achieve the required transfer speed and hardness. However, after salt bath heat treatment, the internal pores of the parts are difficult to clean, leading to corrosion. Furthermore, salt bath heat treatment is an outdated process that has been phased out by the state and poses safety hazards.

[0004] Therefore, a new process method was invented to meet the design requirements of the parts. Summary of the Invention

[0005] To address the aforementioned problems, this invention aims to provide a high-precision accessory housing transmission rod and its heat treatment process.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a high-precision accessory housing transmission rod, comprising a rod body, a through hole on the axis of the rod body, splines at both ends of the rod body, the rod body and the splines being an integral structure, the outer diameter of the rod body being larger than the outer diameter of the splines, and the through hole penetrating the rod body and the splines.

[0007] Preferably, the material of the transmission rod of the casing is 60Si2MnA.

[0008] A heat treatment process for a high-precision accessory housing transmission rod includes the following steps:

[0009] Step 1: Clamping, use nickel-chromium wire to bind the housing and suspend it on the quenching fixture;

[0010] Step 2: Quenching. Heat the fluidized particle furnace to 860±10℃ and hold for 15 minutes. Then, put the accessory casing into the fluidized particle furnace and hold for 7 to 15 minutes before removing it from the furnace and oil cooling.

[0011] Step 3: Degreasing, removing quenching oil stains;

[0012] Step 4: Tempering. Heat the ordinary furnace to 440±20℃ and hold for 15 minutes. Then, put the accessory casing into the ordinary furnace and hold for 60-80 minutes before removing it from the furnace and water cooling.

[0013] Preferably, in step 1, before clamping the gearbox drive rod, the gearbox drive rod is inspected and cleaned with clean acetone, alcohol or FDS166 cleaning agent, and then dried before being installed in the furnace.

[0014] Preferably, in step 2, the heating medium of the fluidized particle furnace is graphite particles.

[0015] Preferably, in step 2, the quenching transfer speed is 3s.

[0016] Preferably, in step 3, the degreasing is carried out in a washing machine or a hot water tank.

[0017] Preferably, after step 4, the surface is polished after being cooled by water to remove the surface oxide color.

[0018] Preferably, the hardness HRC of the polished accessory housing transmission rod is 46-51.

[0019] Preferably, the polished accessory housing transmission rod is protected against rust with rust-preventive oil F20-1.

[0020] Compared with the prior art, the present invention has the following advantages:

[0021] 1. The transmission rod of the casing is quenched using a fluidized bed particle furnace. The heating medium is graphite particles. During the heating process, the parts are completely coated with graphite powder, which can prevent the parts from contacting the air and ensure that the parts are free from oxidation and decarburization. At the same time, the graphite particles will not condense on the surface of the transmission rod of the casing, and the inner hole of the transmission rod of the accessory casing will not be blocked. The quenched parts do not need to be cleaned, and corrosion of the parts can also be prevented.

[0022] 2. The quenching transfer speed of fluidized particle heat treatment technology is only 3 seconds, which is very fast and can meet the hardness requirements of parts. It has a high pass rate and reduces the risk of parts being scrapped.

[0023] 3. After the parts are securely tied with nickel-chromium wire, they are suspended on the quenching fixture, so that the parts are under their own weight, which can effectively prevent the parts from deforming.

[0024] 4. The quenching time using fluid heat treatment technology is only 7 to 15 minutes, and the tempering time is also greatly shortened to only 60 to 80 minutes, which greatly reduces the processing time and improves production efficiency. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the specific embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the accessory housing transmission rod in this invention. Detailed Implementation

[0027] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. However, it should not be construed that the scope of the subject matter of the present invention is limited to the following embodiments. All modifications, substitutions and alterations made based on ordinary technical knowledge and common practices in the art without departing from the above-described technical concept of the present invention are included within the scope of the present invention.

[0028] Reference Figure 1 A high-precision accessory housing transmission rod includes a rod body with a through hole along its axis. Both ends of the rod body are splines, and the rod body and splines are an integral structure. The outer diameter of the rod body is larger than the outer diameter of the splines, and the through hole penetrates both the rod body and the splines. The transmission rod is made of 60Si2MnA material.

[0029] A heat treatment process for a high-precision accessory housing transmission rod includes the following steps:

[0030] Step 1: Clamping. Before clamping the transmission rod of the housing, inspect and clean the transmission rod of the housing. Clean it with clean acetone, let it dry, and then use nickel-chromium wire to tie the housing and hang it on the quenching fixture.

[0031] Step 2: Quenching. Heat the fluidized particle furnace to 865℃, using graphite particles as the heating medium, and hold for 15 minutes. Then, load the accessory casing into the fluidized particle furnace, hold for 15 minutes, and then remove it from the furnace for oil cooling. The quenching transfer speed is 3 seconds.

[0032] Step 3: Degreasing, remove quenching oil stains in a washing machine;

[0033] Step 4: Tempering. Heat the accessory housing in a conventional furnace to 440℃ and hold for 15 minutes. Then, place the accessory housing into the furnace and hold for 70 minutes. Remove from the furnace and water-cool. After water cooling, polish to remove surface oxide. The hardness (HRC) of the polished accessory housing drive rod was measured to be 51. Finally, apply rust-preventive oil F20-1 to the polished accessory housing drive rod for rust prevention.

[0034] The above provides a detailed description of a high-precision accessory housing transmission rod and its heat treatment process provided by the present invention. Specific examples have been used to illustrate the structure and working principle of the invention. The descriptions of the embodiments above are merely for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make various improvements and modifications to the present invention without departing from its principles, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A heat treatment process for a high-precision accessory housing transmission rod, characterized in that: A high-precision accessory housing transmission rod, characterized in that: it includes a rod body, a through hole is provided on the axis of the rod body, splines are at both ends of the rod body, the rod body and the splines are an integral structure, the outer diameter of the rod body is larger than the outer diameter of the splines, the through hole penetrates the rod body and the splines, and the material of the housing transmission rod is 60Si2MnA; The process includes the following steps: Step 1: Clamping, use nickel-chromium wire to bind the housing and suspend it on the quenching fixture; Step 2: Quenching. Heat the fluidized particle furnace to 860±10℃ and hold for 15 minutes. Then, put the accessory casing into the fluidized particle furnace and hold for 7 to 15 minutes before removing it from the furnace and cooling it with oil. The heating medium of the fluidized particle furnace is graphite particles, and the quenching transfer speed is 3 seconds. Step 3: Degreasing, removing quenching oil stains; Step 4: Tempering. Heat the ordinary furnace to 440±20℃ and hold for 15 minutes. Then, put the accessory casing into the ordinary furnace and hold for 60-80 minutes before removing it from the furnace and water cooling.

2. The heat treatment process for the high-precision accessory housing transmission rod according to claim 1, characterized in that: In step 1, before clamping the gearbox drive rod, inspect and clean the gearbox drive rod with clean acetone, alcohol or FDS166 cleaning agent, and then dry it before loading it into the furnace.

3. The heat treatment process for the high-precision accessory housing transmission rod according to claim 1, characterized in that: In step 3, the degreasing is carried out in a washing machine or a hot water tank.

4. The heat treatment process for the high-precision accessory housing transmission rod according to claim 1, characterized in that: Step 4: After cooling in water after baking, polish the surface to remove the oxide color.

5. The heat treatment process for the high-precision accessory housing transmission rod according to claim 4, characterized in that: The hardness HRC of the polished accessory housing transmission rod is 46-51.

6. The heat treatment process for the high-precision accessory housing transmission rod according to claim 4, characterized in that: After polishing, the transmission rod of the accessory housing is protected against rust with rust-preventive oil F20-1.

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