Mounting tool for aero-engine bearing casing stud

Abstract

The utility model relates to a mounting tool for a stud of a bearing casing of an aero-engine. The mounting tool solves the problems existing during stud assembly at present. Comprising a positioning sleeve, the front end of the positioning sleeve is provided with an internal thread matched with an engine front bearing casing stud installation thread, handles are arranged on the two sides outside the positioning sleeve, a movable lead screw is installed in the positioning sleeve, the front end of the movable lead screw is a screw part matched with the internal thread of the positioning sleeve, and the length of the screw part is equal to that of an internal thread hole in the front end of the positioning sleeve. An inner hexagonal hole matched with a hexagonal wrench is formed in the rear end face of the movable lead screw, a force limiting square hole capable of being connected with a force limiting wrench for force limiting operation is formed in the rear end of the positioning sleeve, and the diameter of the rear end of the movable lead screw is larger than the side length of the force limiting square hole. According to the utility model, efficient installation, convenient force limiting and accurate positioning of the stud can be ensured.

Description

Technical Field

[0001] This utility model belongs to the field of threaded fastening assembly of aero-engines, and mainly relates to an installation tool for a bolt post of an aero-engine bearing casing. Background Technology

[0002] The front bearing housing bolt assembly and fastening method is a self-locking structure. Currently, the use of self-locking bolts in aero-engines is becoming increasingly common, and they have largely replaced interference bolts. However, the assembly of double-ended bolts in the self-locking threaded holes of aero-engine housings is a typical bottleneck process with long time consumption and high rework rates. The main technical difficulty lies in the fact that there are no wrench leverage points at both ends of the bolt, and the threaded holes have self-locking properties, making it impossible to screw the bolt threads in and apply torque by hand. In addition, if the bolt is not constrained during the screwing process, self-adjustment will cause the bolt to exceed the perpendicularity standard with the housing surface. The traditional installation method of double-ended bolts is to use two nuts to screw into the threaded end of the bolt, and then apply torque to the upper nut with a wrench to complete the assembly. This method has two main problems: first, the nuts are difficult to push out, and perpendicularity cannot be guaranteed; second, the exposed threaded part is easily squeezed and damaged during the pushing process. Due to the compact structure of the bolt assembly area, it is impossible to position it, so special tooling is required to complete the assembly. Therefore, an installation tool for aero-engine bearing housing bolts was designed to solve the above assembly problems. Utility Model Content

[0003] This utility model provides an installation tool for the bolts of an aero-engine bearing casing, which solves the problems existing in the current assembly of bolts.

[0004] This utility model is achieved through the following technical solution:

[0005] An installation tool for a bolt on an aero-engine bearing housing includes a positioning sleeve. The front end of the positioning sleeve has an internal thread that mates with the bolt on the front bearing housing of the engine. Handles are provided on both sides of the positioning sleeve. A movable lead screw is installed inside the positioning sleeve. The front end of the movable lead screw is a screw part that mates with the internal thread of the positioning sleeve. The rear end face of the movable lead screw has an internal hexagonal hole that mates with a hexagonal wrench. The rear end of the positioning sleeve has a force-limiting square hole that can be connected to a force-limiting wrench for force-limiting operation.

[0006] Furthermore, the length of the movable lead screw is equal to the length of the internal threaded hole at the front end of the positioning sleeve.

[0007] Furthermore, the diameter of the rear end of the movable lead screw is greater than the side length of the force-limiting square hole.

[0008] This invention ensures efficient installation of bolts, convenient force limiting, and precise positioning. Attached Figure Description

[0009] Figure 1 This is a three-dimensional schematic diagram of the entire invention;

[0010] Figure 2 This is a three-dimensional schematic diagram of the components of the present invention;

[0011] Figure 3 This is a schematic diagram illustrating the use of the present invention.

[0012] Figure 4(a) is a three-dimensional schematic diagram of the positioning sleeve;

[0013] Figure 4(b) is a schematic diagram of the positioning sleeve dimensions;

[0014] Figure 5(a) is a three-dimensional schematic diagram of the movable lead screw;

[0015] Figure 5(b) is a schematic diagram of the dimensions of the movable lead screw;

[0016] Figure 6(a) is a three-dimensional schematic diagram of a hexagonal wrench;

[0017] Figure 6(b) is a schematic diagram of the dimensions of a hexagonal wrench. Detailed Implementation

[0018] This utility model discloses an installation tool for the bolts of an aero-engine bearing casing. The tool has three main functions: a) stable clamping of the double-ended bolts; b) torque transmission via a torque wrench; and c) preventing the bolts from loosening during tool unloading. Based on these requirements, the tool is designed as follows:

[0019] like Figure 1 As shown in Figure 6, an installation tool for the bolts of a certain type of engine front bearing housing, designed according to assembly functional requirements, includes a positioning sleeve 1; a matching thread 2 is provided in the front end of the positioning sleeve 1, which is compatible with the installation thread of the bolts of the certain type of engine front bearing housing; handles 3 are provided on both sides of the positioning sleeve 1 for holding the installation tool in hand; a movable lead screw 4 is installed inside the positioning sleeve 1; the front end of the movable lead screw 4 has an external matching thread 6 that mates with the matching thread 2; the rear end has an internal hexagonal hole 7; it moves within the positioning sleeve 1 by rotating the matching thread through a hexagonal wrench 8; a force-limiting square hole 5 is provided at the rear end of the positioning sleeve 1, which is connected to a force-limiting wrench for force-limiting operation.

[0020] Specifically:

[0021] The movable lead screw, with a 20mm movement space within the sleeve, allows the device to adjust and lock the position according to the length of the bolt. Furthermore, an internal hexagonal hole is provided at the rear end of the movable lead screw, allowing it to move via a hexagonal wrench, thereby achieving a stop and limit on the bolt axis. A force-limiting socket can be connected to a force-limiting wrench to apply tightening torque. Simultaneously, the radius of the movable lead screw is larger than the size of the force-limiting square hole, ensuring that the movable lead screw cannot be dislodged from the positioning sleeve of the installation tool.

[0022] The assembly process of the double-headed stud installation tool of this utility model consists of the following seven steps:

[0023] (1) First screw the nut into one side of the double-threaded stud of the front bearing housing bolt;

[0024] (2) Then screw a portion of the double-threaded bolt of the front bearing housing into the positioning sleeve of the installation tool;

[0025] (3) Next, use a hex wrench to rotate the internal hexagonal hole and move the movable screw towards the front end of the screw thread until it stops, thus achieving initial positioning.

[0026] (4) Then, holding the handle, screw the front bearing housing bolt threads completely into the installation tool;

[0027] (5) Then, use a force-limiting wrench to connect to the force-limiting square hole at the rear end of the positioning sleeve to limit the force;

[0028] (6) Measure whether the elongation of the bolt after the force limit meets the installation requirements;

[0029] (7) Finally, after installation is complete, use a hex wrench again to rotate in the opposite direction of assembly with the internal hexagonal hole to move the rear end of the movable screw until the screw is loosened, and check the integrity of the screw.

[0030] After using this installation tool to assemble double-headed studs, the first-time assembly qualification rate increased from 45% to 96%. In addition, the assembly time for a single stud was reduced from 0.5 hours to 0.1 hours, effectively improving quality and efficiency.

Claims

1. An installation tool for the bolts of an aircraft engine bearing casing, characterized in that: The device includes a positioning sleeve. The front end of the positioning sleeve has an internal thread that mates with the mounting thread of the engine front bearing housing stud. The positioning sleeve has handles on both sides. A movable lead screw is installed inside the positioning sleeve. The front end of the movable lead screw is a screw part that mates with the internal thread of the positioning sleeve. The rear end face of the movable lead screw has an internal hexagonal hole that mates with a hexagonal wrench. The rear end of the positioning sleeve has a force-limiting square hole that can be connected to a force-limiting wrench for force-limiting operation.

2. The installation tool for the bearing casing bolts of an aero-engine as described in claim 1, characterized in that: The length of the movable lead screw is equal to the length of the internal threaded hole at the front end of the positioning sleeve.

3. The installation tool for the bearing casing bolts of an aircraft engine according to claim 1, characterized in that: The diameter of the rear end of the movable lead screw is greater than the side length of the force-limiting square hole.

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