CN108518404A - Carbon fiber compound air mandrel and preparation method thereof - Google Patents

Abstract

The invention relates to a carbon fiber composite hollow shaft and a preparation method thereof. The carbon fiber composite hollow shaft includes an inner tube, an outer tube, and a plurality of reinforcement structures; the plurality of reinforcement structures are arranged between the outer wall of the inner tube and the inner wall of the outer tube, and the plurality of reinforcement structures Arranged along the circumferential direction of the inner tube and the outer tube, the lengths of the plurality of reinforced structural members extend along the axial direction of the inner tube and the outer tube, and the material of the hollow shaft is carbon fiber reinforced resin matrix composite material. The invention greatly improves the axial strength of the hollow shaft made of composite material, and the design of the reinforcement structure improves the rigidity of the longitudinal section of the shaft, thereby being easy to popularize. And through the rational design of the structure, it not only effectively reduces the weight of the hollow shaft, but also ensures the mechanical performance requirements of the hollow shaft.

Description

Carbon fiber composite hollow shaft and preparation method thereof

technical field

The invention relates to a carbon fiber composite high-strength and high-rigidity hollow shaft and a preparation method thereof.

Background technique

Industrial equipment is inseparable from the use of bearing shafts. There are various types of shafts. As far as the most obvious different types are concerned, they are divided into hollow shafts and solid shafts. According to the analysis of material mechanics, when the rotating shaft transmits torque, from the perspective of the radial section, the effect of transmitting the effective torque is greater at the outer part, so the hollow shaft can generally be used instead of the solid shaft to reduce the weight of the rotating shaft.

With the development of material forming technology, the hollow shaft will gradually replace the traditional solid shaft due to its characteristics of material saving, light weight and good mechanical properties, and become the preferred choice for shaft parts. Traditional hollow shaft processing methods include free forging, radial precision forging, machining, etc., but the processing accuracy is low and there are waste materials, time-consuming and other shortcomings.

At present, the drive shaft parts of automobiles and ships and various idlers are made of metal. Considering that the force of the drive shaft is relatively complicated, especially to withstand a large torque, the shaft made of metal will lead to a heavy weight of the product. Therefore, how to realize lightweight is a research hotspot for those skilled in the art.

Contents of the invention

The technical problem to be solved by the present invention is to provide a high-strength and high-rigidity carbon fiber composite hollow shaft and a preparation method thereof. The preparation process of the hollow shaft is simple and easy to popularize.

To achieve the above object, the technical solution disclosed in the present invention is:

A carbon fiber composite hollow shaft, the carbon fiber composite hollow shaft includes an inner tube, an outer tube, and a plurality of reinforcing structural members; the plurality of reinforcing structural members are arranged between the outer wall of the inner tube and the inner wall of the outer tube , the plurality of reinforcement structures are arranged along the circumference of the inner tube and the outer tube, the length of the plurality of reinforcement structures extends along the axial direction of the inner tube and the outer tube, and the material of the hollow shaft is Carbon fiber reinforced resin matrix composites.

In the above solution, the cross-sectional shape of each reinforcing structural member is fan-shaped, trapezoidal, triangular, I-shaped or rectangular.

In the above solution, the cross-sectional shape of each reinforcing structural member is circular.

In the above solution, the fiber composite hollow shaft further includes fillers filling the gaps between the multiple reinforced structural members, and the fillers are mixed lightweight fillers of carbon fibers and resins.

In the above solution, the wall thickness of each reinforcing structural member is 2-20 mm.

In the above solution, the length of the hollow shaft is 0.1-20m, and the outer diameter is 10-500mm.

In the above solution, the wall thickness of the inner tube and the outer tube is 3-40mm.

In the above solution, the resin includes epoxy resin, vinyl ester resin, unsaturated polyester resin or phenolic resin.

In the preparation method of the carbon fiber composite hollow shaft, the reinforced structure is made of carbon fiber pultrusion; the inner tube and the outer tube are made of carbon fiber yarn winding.

The invention has the following beneficial effects: mechanical analysis and design are carried out according to the requirements of bearing load, and the strength of the force direction is correspondingly enhanced by adopting the process of pultrusion combined with hoop winding, which greatly improves the strength of the composite hollow shaft along the axial direction. The strength, the design of the reinforced structural member improves the stiffness of the longitudinal section of the shaft, which is easy to promote. And through the rational design of the structure, it not only effectively reduces the weight of the hollow shaft, but also ensures the mechanical performance requirements of the hollow shaft.

Description of drawings

FIG. 1 is an overall longitudinal sectional view of the carbon fiber composite hollow shaft provided in Example 1. FIG.

FIG. 2 is a longitudinal sectional view of a reinforcing structural member in Embodiment 1. FIG.

Fig. 3 is an overall longitudinal sectional view of the carbon fiber composite hollow shaft provided in Example 2.

Detailed ways

The present invention will be further clarified below in conjunction with the examples and accompanying drawings, but the content of the present invention is not limited to the following examples, and the examples should not be regarded as limiting the present invention.

As shown in FIG. 1 to FIG. 3 , it provides a carbon fiber composite hollow shaft according to the present invention, and the carbon fiber composite hollow shaft includes an inner tube 3 , an outer tube 1 and a plurality of reinforcing structural parts 2 . Multiple reinforcement structures 2 are arranged between the outer wall of the inner tube 3 and the inner wall of the outer tube 1, the multiple reinforcement structures 2 are arranged along the circumference of the inner tube 3 and the outer tube 1, and the lengths of the multiple reinforcement structures 2 are along the Extending along the axial direction of the inner tube 3 and the outer tube 1 , the hollow shaft is made of carbon fiber reinforced resin-based composite material. Resins include epoxy resins, vinyl ester resins, unsaturated polyester resins or phenolic resins.

The cross-sectional shape of each reinforcement structure 2 is fan-shaped, trapezoidal, circular, triangular, I-shaped or rectangular. The wall thickness of each reinforced structural member 2 is 2-20mm. The length of the hollow shaft is 0.1-20m, and the outer diameter is 10-500mm. The wall thickness of the inner tube 3 and the outer tube 1 is 3-40mm.

The preparation method of the above-mentioned carbon fiber composite hollow shaft is as follows: the material of the hollow shaft is carbon fiber reinforced resin-based composite material, which is made by pultrusion combined with hoop winding process. Among them, a plurality of reinforced structural parts 2 are made of carbon fiber pultrusion; the inner tube 3 and the outer tube 1 are made of carbon fiber yarn winding. Firstly, the carbon fiber reinforced resin-based inner pipe 3 is made by winding, and then a plurality of reinforcing structural parts 2 are installed, and finally, the carbon fiber reinforced resin-based outer pipe 1 is made by winding.

Example 1

This embodiment provides a high-strength and high-rigidity hollow shaft, which is made of carbon fiber reinforced epoxy resin composite material. After calculation, the designed outer diameter is 200mm, and its length is 1.2m.

The reinforcement structure 2 adopts a hollow fan-shaped structure and is formed by pultrusion. The size is shown in Figure 2, a total of 32, each of which is bonded with epoxy resin, and the carbon fiber uses the T700 model. The longitudinal section of the entire hollow shaft is shown in Figure 1. After testing, its density is 1600kg/m ³ . RGT-4000 universal testing machine is used to carry out the tensile test at room temperature according to the standard GB/T 2568-1995. The distance between the chucks is 50mm and the tensile rate is 2mm/min. The tensile strength is 1613.4-2225.9MPa, and the tensile modulus is 148.7-157.4GPa. The change is related to the carbon fiber content. In practical application, it is determined according to the comprehensive consideration of demand and cost. The product is tested according to QC/T29082-1992 technical condition standard of automobile transmission shaft assembly: the radial runout of the shaft is measured with the radial runout tester of the ring gear, and many experiments show that the radial runout of the shaft tube is ≤0.8mm. Test the stress and strain of the transmission shaft by the strain gauge method, change the torque component to 2-5kN m, use the formula:

In the formula: n——safety factor;

M _s ——Static torsional yield torque of the transmission shaft, N m;

M _{g max} —— rated load torque of drive shaft, N·m.

The safety factor is obtained in the range of 2 to 2.5. According to the JB 3741 regulations, when the weight falls freely at a height of 1.25m, the transmission shaft does not break and damage. The test on the transmission shaft torsional fatigue testing machine shows that its service life is greater than 150,000 cycles.

Example 2

This embodiment provides a high-strength and high-rigidity hollow shaft, which is made of carbon fiber reinforced epoxy resin composite material. After calculation, the designed outer diameter is 350mm, and the reinforced structural parts 2 are round tubes, 14 in total. The dimensions of each part are shown in Table 2.

The gaps between the reinforced structural members 2 are filled with a composite material filler 4 composed of a mixture of carbon fiber and epoxy resin. The longitudinal section of the entire hollow shaft is shown in FIG. 3 . After testing, its density is 1600kg/m ³ . RGT-4000 universal testing machine is used to carry out the tensile test at room temperature according to the standard GB/T 2568-1995. The distance between the chucks is 50mm and the tensile rate is 2mm/min. The tensile strength is 1613.4-2225.9MPa, and the tensile modulus is 148.7-157.4GPa. The change is related to the carbon fiber content. In practical application, it is determined according to the comprehensive consideration of demand and cost. The radial runout of the shaft is measured with the radial runout tester of the ring gear, and many experiments show that the radial runout of the shaft tube is ≤0.8mm. The stress and strain of the transmission shaft are measured by the strain gauge method, and the torque component is changed to 1-3kN·m, and the safety factor is obtained at 1.8-2.3.

Table 1 Embodiment 1 inner pipe and outer pipe size

Dimensions of each part of Table 2 Embodiment 2

Embodiments of the present invention have been described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementations, and the above-mentioned specific implementations are only illustrative, rather than restrictive. Those of ordinary skill in the art will Under the enlightenment of the present invention, many forms can also be made without departing from the gist of the present invention and the protection scope of the claims, and these all belong to the protection of the present invention.

Claims (9)

1. a kind of carbon fiber compound air mandrel, which is characterized in that the carbon fiber compound air mandrel includes inner tube, outer tube and more A enhancing structure part；The multiple enhancing structure part is set between the outer wall of said inner tube and the inner wall of the outer tube, described Multiple enhancing structure parts are along the circumferential array of inner and outer tubes, and the length of the multiple enhancing structure part is along said inner tube and outer The axial direction of pipe extends, and the material of the hollow shaft is carbon fiber enhancement resin base composite material.

2. carbon fiber compound air mandrel as described in claim 1, which is characterized in that the section shape of each enhancing structure part Shape is fan-shaped, trapezoidal, triangle, I-shaped or rectangle.

3. carbon fiber compound air mandrel as described in claim 1, which is characterized in that the section shape of each enhancing structure part Shape is circle.

4. carbon fiber compound air mandrel as claimed in claim 3, which is characterized in that the fiber composite hollow shaft further includes filling out The filler in the gap between multiple enhancing structure parts is filled, the filler is the mixing light filler of carbon fiber and resin.

5. carbon fiber compound air mandrel as described in claim 1, which is characterized in that the wall thickness of each enhancing structure part is 2~ 20mm。

6. carbon fiber compound air mandrel as described in claim 1, which is characterized in that the hollow shaft length is 0.1~20m, Outer diameter is 10~500mm.

7. carbon fiber compound air mandrel as described in claim 1, which is characterized in that the wall thickness of said inner tube and outer tube be 3~ 40mm。

8. carbon fiber compound air mandrel as described in claim 1, which is characterized in that the resin includes epoxy resin, ethylene Base ester resin, unsaturated polyester resin or phenolic resin.

9. the preparation method of carbon fiber compound air mandrel as described in claim 1, which is characterized in that the enhancing structure part by Carbon fiber pultrusion is made；Said inner tube and outer tube are made of carbon fiber yarn winding.