阅读说明：本技术 盾构掘进机主驱动橡胶密封件及其成型方法 (Main drive rubber sealing element of shield tunneling machine and forming method thereof ) 是由 雷霖 马自立 蔡伟强 王宇 刘锐源 于 2021-08-12 设计创作，主要内容包括：本发明公开盾构掘进机主驱动橡胶密封件及其成型方法,该方法包括如下步骤：S1.通过橡胶挤出机对丁腈橡胶材料进行挤出,得到预成型的半成品；S2.根据分段模具的长度,将预成型的半成品进行裁断,并通过颚式平板硫化机进行分段模压硫化,得到两端未完全熟化的分段产品；S3.对两端未完全熟化的分段产品进行切口,并对切口进行处理,最后通过接头模具对两端未完全熟化的处理过切口的分段产品进行成环接头,最终得到整圈成品。本发明在工艺方法中通过对分段模具、分段产品切口处理、接头模具等的设计及控制,保证了成型方法的低成本、高精度、优良的外观、高可靠性要求。(The invention discloses a main drive rubber sealing element of a shield tunneling machine and a forming method thereof, wherein the method comprises the following steps: s1, extruding a nitrile rubber material through a rubber extruder to obtain a preformed semi-finished product; s2, cutting the preformed semi-finished product according to the length of the segmented mold, and performing segmented mold pressing vulcanization through a jaw plate vulcanizing machine to obtain a segmented product with two ends not completely cured; and S3, cutting the segmented product of which the two ends are not completely cured, processing the cut, and finally performing ring-forming joint on the cut-processed segmented product of which the two ends are not completely cured through a joint mould to finally obtain a whole ring finished product. The invention ensures the requirements of low cost, high precision, excellent appearance and high reliability of the forming method by designing and controlling the sectional die, the sectional product notch treatment, the joint die and the like in the process method.)

1. The forming method of the main drive rubber sealing element of the shield tunneling machine is characterized by comprising the following steps:

s1, extruding a nitrile rubber material through a rubber extruder to obtain a preformed semi-finished product;

s2, cutting the preformed semi-finished product according to the length of the segmented mold, and performing segmented mold pressing vulcanization through a jaw plate vulcanizing machine to obtain a segmented product with two ends not completely cured;

and S3, cutting the segmented product of which the two ends are not completely cured, processing the cut, and finally performing ring-forming joint on the cut-processed segmented product of which the two ends are not completely cured through a joint mould to finally obtain a whole ring finished product.

2. The molding method according to claim 1, wherein the nitrile rubber material has a hardness of between 70A and 90A Shore hardness in S1.

3. The molding method according to claim 1, wherein in S2, the segment mold comprises a linear or curvature-containing mold.

4. The molding method according to claim 2 or 3, wherein in the step S2, in the step S of carrying out the segmented mold pressing and vulcanizing by the jaw plate vulcanizing machine, the length of the jaw plate vulcanizing machine is 0.5-3 m, the width of the jaw plate vulcanizing machine is 0.3-1 m, and the plate surfaces at the two ends of the jaw plate vulcanizing machine are subjected to cooling treatment to ensure that the product with the length of not less than 20cm at the two ends of the mold is not completely cured.

5. The molding method according to claim 4, wherein the temperature of the two-end temperature zone and the temperature of the middle temperature zone of the jaw plate vulcanizer are 90 ℃ and 160 ℃.

6. The molding method according to claim 5, wherein in S3, the angle range of the cut includes 15 ° oblique cut to 90 ° straight cut.

7. The molding method according to claim 6, wherein in S3, the curvature of the working surface of the joint mold matches the curvature of the working surface of the segment mold, the two sides of the joint mold are provided with the pressing and fixing devices comprising bolts, and the middle joint part of the joint mold is provided with the movable pressing plate.

8. The main driving rubber sealing element of the shield tunneling machine manufactured according to the molding method of claim 1, wherein the sealing element is of an annular structure, the cross section of the sealing element is hook-shaped, and the sealing element comprises a longitudinal sealing element main body and a sealing lip body arranged on the inner ring side or the outer ring side.

Technical Field

The invention belongs to the technical field of shield tunneling machine sealing parts, and particularly relates to a shield tunneling machine main drive rubber sealing part and a forming method thereof.

Background

In China, the shield machine plays a great role in the construction field of urban subways and river-crossing ocean tunnels and the tunnel engineering of railways, highways, municipal administration, hydropower and the like. The main drive seal is an annular seal wear-resistant elastic unit arranged between a rotating main bearing and a non-rotating headstock, is a key part of the main bearing, particularly a main drive bearing seal positioned at the front end of the main bearing, and is mainly used for preventing muck in a main drive cutter head of the shield from entering the main bearing gear box and washing and lubricating a main drive bearing rotary sliding mechanism, a seal part and a mechanism in contact with silt, and once the seal fails, the silt enters the bearing to damage the main bearing and directly cause the shield to be incapable of tunneling. The general main driving rubber seal comprises two types, namely rubber VD seal and rubber single-lip seal, and the main application material is nitrile rubber. From the sealing direction, the VD seal and the single-lip rubber seal are an inner seal and an outer seal. Generally, the seal lip is outward for an outer seal and inward for an inner seal.

The existing method for forming the main drive rubber sealing element of the shield tunneling machine generally comprises three types: in the first category, a whole ring mold is adopted for compression molding. The product size precision of the forming method is relatively high, but the mold processing cost is extremely high, a large-scale flat vulcanizing machine is also needed for process matching, the number of different size specifications of the same section of the main driving seal of the shield tunneling machine is extremely large, the forming method has extremely high mold cost pressure and is not suitable for commercial production; the second is a forming method of turning by adopting a mechanical processing means after pressing a rubber cylinder material, the forming method has high product size precision, but has certain requirements on the hardness of a rubber material of a product, can influence the resilience and the compression permanent deformation performance of the nitrile rubber to a certain extent, and has certain risks in the using process; the third is a process method of extrusion microwave vulcanization molding back joint ring forming, the nitrile rubber used in the molding method is a special formula material, and a special vulcanization system and a plasticizing system are provided, which can cause certain reduction of the physical properties of the material. Particularly in the final looping process, the already cured material joints can cause the joint site to lose strength. In addition, the product section size precision is low. Therefore, the problem of forming the main driving rubber sealing element of the shield tunneling machine is urgently needed to be solved according to the requirements of low mould cost, excellent material performance, adaptability of forming process, high product size precision and high reliable process control.

Disclosure of Invention

The invention provides a main driving rubber sealing element of a shield tunneling machine and a forming method thereof, which solve the problem of ring formation of the main driving rubber sealing element of the shield tunneling machine in the prior art.

In order to achieve the purpose, the technical scheme of the invention is as follows:

the forming method of the main drive rubber sealing element of the shield tunneling machine comprises the following steps:

s1, extruding a nitrile rubber material through a rubber extruder to obtain a preformed semi-finished product;

s2, cutting the preformed semi-finished product according to the length of the segmented mold, and performing segmented mold pressing vulcanization through a jaw plate vulcanizing machine to obtain a segmented product with two ends not completely cured;

and S3, cutting the segmented product of which the two ends are not completely cured, processing the cut, and finally performing ring-forming joint on the cut-processed segmented product of which the two ends are not completely cured through a joint mould to finally obtain a whole ring finished product.

Further, in S1, the hardness of the nitrile rubber material is between 70A and 90A in Shore hardness.

Further, in S2, the segmented mold includes a linear or curvature-containing mold.

Further, in S2, in the segmented mold pressing vulcanization process of the jaw plate vulcanizing machine, the length of the vulcanizing machine is 0.5-3 m, the width of the vulcanizing machine is 0.3-1 m, the plate surfaces at two ends of the vulcanizing machine are cooled, and the fact that products with the lengths of not less than 20cm at two ends of the mold are not completely cured is guaranteed.

Furthermore, the temperature of the temperature zones at the two ends of the jaw plate vulcanizing machine is 90 ℃, and the temperature of the temperature zone at the middle part is 160 ℃.

Further, in S3, the angle range of the cut includes a 15 ° oblique cut to a 90 ° straight cut.

Further, in the step S3, the curvature of the working surface of the joint die is matched with that of the working surface of the sectional die, the two sides of the joint die are provided with a pressing and fixing device comprising a bolt, and the middle joint part of the joint die is provided with a movable pressing plate.

The main driving rubber sealing element of the shield tunneling machine manufactured according to the molding method is of an annular structure, the cross section of the sealing element is in a hook shape, and the sealing element comprises a longitudinal sealing element main body and a sealing lip body arranged on the inner ring side or the outer ring side.

Compared with the prior art, the invention has the following beneficial effects:

1. the forming method of the invention ensures the requirements of low cost, high precision, excellent appearance and high reliability of the forming method by designing and controlling the segmentation die, the segmentation product notch treatment and the joint die.

2. The invention adopts a molding method of mold pressing vulcanization, and greatly ensures the dimensional accuracy of the product section.

3. The joint mould and the joint process used by the invention have high joint part strength which can reach more than 95% of the material performance of the body.

4. The forming method has simple process, and can not be scrapped integrally even if unqualified products appear in the intermediate process.

5. The molding method of the invention has the advantages of low cost of the used mold, universality in a certain curvature range and certain flexibility.

Drawings

FIG. 1 is a schematic cross-sectional view of a segmented mold according to an embodiment of the present invention.

Fig. 2 is a top view of fig. 1.

Fig. 3 is a schematic cross-sectional view of a joint mold according to an embodiment of the present invention.

Fig. 4 is a top view of fig. 3.

Fig. 5 is a schematic diagram of a manufactured main driving rubber sealing element of the shield tunneling machine.

Fig. 6 is a schematic diagram of another manufactured main driving rubber sealing element of the shield tunneling machine.

101-a sealing element main body, 102-a sealing lip body, 2-a segmented mold, 3-a positioning pin, 4-a joint mold, 5-a bolt and 6-a movable cover plate.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in further detail with reference to embodiments, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Aiming at the problems in the background art, the applicant provides a new solution from the perspective of a forming process, presses a segmented product with uncured nitrile rubber main drive sealing left at two ends through a segmented mold scheme, and then forms a ring through a joint mold joint. Compared with other modes, the invention ensures the requirements of low cost, high precision, excellent appearance and high reliability of the forming method by designing and controlling the segmentation die, the segmentation product notch treatment, the joint die and the like in the process method.

Example (b):

in this embodiment, a single-lip seal of the main driving rubber of the shield tunneling machine is taken as an example, referring to fig. 5 and 6, the seal is in an annular structure, the cross section of the seal is in a hook shape, the seal comprises a longitudinal seal main body 101 and a seal lip body 102 arranged on the inner ring side or the outer ring side, and the VD seal forming method is consistent with the single-lip seal.

Referring to FIGS. 1 and 2, 50kg of nitrile rubber was extruded in an extruder equipped with a die plate of single-lip seal shape. After the extrusion was completed, the pre-formed semi-finished product was cut to 1.5 m. The sectional die with the length of 1.5m is arranged on a jaw plate vulcanizing machine with the plate surface size of 1.5 x 0.5m, the temperature of temperature zones at two ends of the jaw plate vulcanizing machine is set to be 90 ℃, and the temperature of a temperature zone in the middle of the jaw plate vulcanizing machine is set to be 160 ℃. When the temperatures of the jaw plate vulcanizing machine and the sectional mold 2 reach the set temperature, putting a 1.5m pre-molded semi-finished product into the sectional mold 2, closing and pressurizing the mold and exhausting for 2-3 times, setting the mold closing pressure to be 15MPa, positioning by using a positioning pin 3 during mold closing, and vulcanizing for 20 min. After the vulcanization time is over, the segment mould 2 is opened and the vulcanized segment product is taken out of the mould cavity.

At this time, both ends of the segmented product are not completely cured; the segmented product, both ends of which are not completely cured, is subjected to a 45 ° incision process by a cutter, and in other embodiments, the angle range of the incision includes any angle from 15 ° to 90 °.

Referring to fig. 3 and 4, the above process is repeated to prepare a segmented product having a 45 ° cut and not completely cured at both ends.

The joint mold 4 was mounted on a jaw press vulcanizer having a plate surface size of 0.5 × 0.5m, the jaw press vulcanization temperature was set to 160 ℃, the vulcanization pressure was set to 15MPa, and the vulcanization time was set to 20 min. Filling the two segmented products which contain 45-degree notches and are not completely cured at two ends into a segmented mold 2, fixing the segmented products on two sides of a joint mold 4 by using a pressing and fixing device containing bolts 5, covering a movable pressing plate at the middle joint part, closing and pressing the mold, and positioning by using a positioning pin 3 during mold closing. After the vulcanization time is over, the joint mould 4 is opened, the bolts 5 of the fixing device are removed, the movable cover plate 6 is removed, and the segment product which is already butted is taken out.

Repeating the processes to finally complete the butt joint and the ring formation of the whole ring product.

In order to test the tensile strength of the joint site material, samples were prepared by grinding the butted segmented products, and samples containing the joint site and samples containing no joint site were prepared as test pieces having a thickness of 2 mm. And testing the hardness and tensile property of the material according to GB/T531.1-2008 and GB/T528-2009 test standards.

TABLE 1 comparison of tensile Property test data for bulk Material and Joint site

As can be seen from Table 1, the samples containing the joint sites and the samples containing no joint sites were subjected to the performance test by grinding. The joint part has excellent performance, is basically close to the performance test data of the body material, and has higher reliability.

The above are specific embodiments of the present invention, but the structural features of the present invention are not limited thereto, and the present invention can be applied to similar products, and any changes or modifications within the scope of the present invention by those skilled in the art are covered by the claims of the present invention.