CN114682999A - Remanufacturing process of central revolving body of shield tunneling machine - Google Patents
Remanufacturing process of central revolving body of shield tunneling machine Download PDFInfo
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- CN114682999A CN114682999A CN202210280864.8A CN202210280864A CN114682999A CN 114682999 A CN114682999 A CN 114682999A CN 202210280864 A CN202210280864 A CN 202210280864A CN 114682999 A CN114682999 A CN 114682999A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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- Y02T10/64—Electric machine technologies in electromobility
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Abstract
The invention provides a remanufacturing process of a central revolving body of a shield tunneling machine, which comprises the remanufacturing process of a central revolving body stator, and comprises the following steps: s1, material preparation: the remanufactured central revolving body stator is made of an integral stainless steel pipe instead of the original combination of a carbon steel base layer and copper pile on the inner surface; s2, primary test: carrying out size and quality inspection on the stainless steel pipe; s3, blanking: sawing a stainless steel pipe according to the drawing and the machining amount; s4, turning: processing the stainless steel pipe according to the drawing design and the surface roughness requirement; s5, secondary inspection: inspecting the size and the surface roughness of the processed stator; s6, surface nitriding treatment: and carrying out ion nitriding treatment on the stator subjected to secondary inspection. The invention can solve the problems of environmental pollution, high repair cost and poor repair effect of the existing repair technology.
Description
Technical Field
The invention relates to the technical field of shield tunneling machines, in particular to a remanufacturing process of a central revolving body of a shield tunneling machine.
Background
Shield tunnel boring machine, shield machine for short. The engineering machine is a super-huge tunnel tunneling special engineering machine integrating light, mechanical, electrical, hydraulic, sensing and information technologies, has the functions of excavating and cutting soil bodies, conveying soil residues, assembling tunnel linings, measuring, guiding, correcting deviation and the like, is high in tunneling speed, high in automation degree, low in labor intensity of personnel, high in construction quality and safety, small in influence on surface settlement and environment, and is widely applied to tunnel engineering of subways, railways, highways, municipal administration, hydropower and the like at present.
The central revolving body is a key part of the shield machine, is positioned between the soil bin partition plate and the main drive, mainly comprises a stator and a rotor, the stator is connected with other fixed parts, the rotor rotates along with the cutter head, and the central revolving body has the function of conveying liquid substances such as muck improving materials, traveling cutter hydraulic oil, cutter abrasion device sealing oil and the like to the shield soil bin and the cutter head.
The shield machine has the advantages that the operation time of the shield machine is gradually increased, in addition, the conveying liquid contains granular substances, and the central rotary stator, the rotor and the seal continuously rotate and rub to cause seal abrasion and aging failure, the contact surface of the stator and the rotor is abraded, the chromium coating on the surface of the rotor is abraded, corroded and peeled off, the problems of seal leakage and independent channel cavity series are caused, the oil conveying efficiency is finally reduced, even the phenomenon of incapability of conveying is caused, the tunneling of the shield machine is seriously influenced, and the shield machine needs to be maintained before tunneling every time. If a method of replacing a new part is adopted during maintenance, the purchase period is long, and the cost is too high, so that the central revolving body is generally repaired by adopting a maintenance mode at home at present.
The stator material of the central revolving body is in a combined form of carbon steel base layer and inner surface copper stacking, various grooves are arranged inside the stator material, the structure is compact, the machining precision is high, and the conventional repairing process flow is as follows: cleaning (physical and chemical) → inspection (crack and abrasion amount) → primary rough machining → surfacing → secondary rough machining → finish machining, and the repair process is large in deformation during welding, large in repair difficulty and high in repair cost, and is similar to the cost of purchasing new parts.
The rotor of the central revolving body is formed by machining a forged solid shaft, a plurality of deep long holes are arranged in the solid shaft and used as fluid channels, a chromium coating is covered on the surface of the solid shaft, and the current common repair process flow is as follows: cleaning (physical and chemical) → inspection (crack and abrasion amount) → primary rough machining → repair welding → secondary rough machining → brush plating (recovery of size) → finish machining (fine grinding), the repair process has high repair cost, the surface chromium plating process is not environment-friendly, the repair period is long, and the chromium plating layer is easy to peel off subsequently.
Disclosure of Invention
Aiming at the prior art, the invention provides a remanufacturing process of a central revolving body of a shield machine, which aims to solve the problems of environmental pollution, high repairing cost and poor repairing effect of the existing repairing technology.
The invention provides a remanufacturing process of a central revolving body of a shield tunneling machine, which comprises the remanufacturing process of a central revolving body stator, and comprises the following steps:
s1, material preparation: the remanufactured central revolving body stator is made of an integral stainless steel pipe instead of the original combination of a carbon steel base layer and copper pile on the inner surface;
s2, primary test: carrying out size and quality inspection on the stainless steel pipe;
s3, blanking: sawing a stainless steel pipe according to the drawing and the machining amount;
s4, turning: processing the stainless steel pipe according to the drawing design and the surface roughness requirement;
s5, secondary inspection: inspecting the size and the surface roughness of the processed stator;
s6, surface nitriding treatment: and carrying out ion nitriding treatment on the stator subjected to secondary inspection.
Preferably, the method also comprises a repairing process of the central revolving body rotor, which comprises the following steps:
s1, cleaning: degreasing and decontaminating the central revolving body rotor by adopting gasoline or alcohol;
s2, chromium stripping: carrying out chromium stripping treatment on the chromium coating which falls off or has pockmarks;
s3, primary test: detecting whether the surface of the rotor base material has cracks and pit defects or not, and measuring the abrasion loss;
s4, surface turning: according to the measured abrasion loss, turning the surface of the rotor by using a lathe to remove the abrasion mark;
s5, surfacing of the wear-resistant welding wire: manufacturing a plurality of round wooden plugs, plugging the passage holes on the surface of the rotor, and performing wear-resistant surfacing on the surface of the rotor by using a wear-resistant welding wire;
s6, rough machining: carrying out surface turning on the rotor subjected to surfacing by using a lathe;
s7, finishing: carrying out fine grinding treatment on the surfaces of the rotors by using a grinding machine;
s8, secondary inspection: inspecting the size and the surface roughness of the processed rotor;
s9, surface nitriding treatment: and carrying out surface nitriding treatment on the rotor subjected to secondary inspection.
In the remanufacturing process of the central revolving body stator, preferably, the stainless steel pipe is an SS304 stainless steel pipe.
Preferably, in S3, the cut allowance of the stainless steel pipe saw is 10-15 mm.
Preferably, in S6, when the stator is subjected to ion nitriding treatment, the process parameters are as follows: the inter-electrode voltage 520-550V, the mixing ratio of N2 and H2 is 1: 3, the furnace pressure is 240-260Pa, the ion nitriding temperature is 420 ℃, and the heat preservation time is 6 h.
In the repairing process of the central revolving body rotor, preferably, in S2, the concrete operations of the chromium removing process are: the rotor was etched in a hydrochloric acid solution, subjected to alkali neutralization treatment and water washing until the chromium plating layer was completely removed.
Preferably, in S5, the overlay welding is submerged arc welding, and the welding process parameters are as follows: the rotor is uniformly heated to 300 ℃ before welding, welding materials are Stellite 225B, the diameter is 4mm, welding flux is SJ101, the specification is 10-60 meshes, direct current reverse connection is adopted, the current is 360-plus 400A, the voltage is 30-34V, the speed is 50-60cm/min, the rotating speed is 0.65-0.75r/min, and the heat preservation is carried out for 1h after welding.
Preferably, in S9, the rotor is subjected to ion permeationDuring nitrogen treatment, the process parameters are as follows: interpolar voltage 520-550V, N2And H2The mixing ratio is 1: 3, the furnace pressure is 240-260Pa, the ion nitriding temperature is 560 ℃, and the heat preservation time is 8 h.
Compared with the prior art, the invention has the beneficial effects that:
1. the stator is remanufactured by adopting a manufacturing process of stainless steel and ion nitriding treatment, the traditional design of a carbon steel base layer and copper pile is cancelled, the manufacturing cost is similar to the repairing cost of the traditional stator, but the manufacturing process is simpler, the manufacturing difficulty is lower, the corrosion resistance and the wear resistance are better, the subsequent repairing process is simpler and the repairing cost is lower.
2. Compared with the old surface chromium plating repair process, the ion nitriding process adopted by the invention is more green, environment-friendly and energy-saving, has better corrosion resistance and lower cost.
Drawings
FIG. 1 is a schematic flow chart of a remanufacturing process of a core rotating body stator in an embodiment of the invention.
FIG. 2 is a schematic view of a process for repairing a central rotor of a rotary body according to an embodiment of the present invention.
FIG. 3 is a schematic structural diagram of a central rotor stator according to an embodiment of the present invention.
Fig. 4 is a schematic structural view of a center rotary body rotor in the embodiment of the present invention.
Detailed Description
In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further explained below by combining the specific drawings.
Examples
A remanufacturing process of a central revolving body of a shield tunneling machine is shown in figures 1 and 3 and comprises the following steps of remanufacturing a central revolving body stator:
s1, material preparation: the remanufactured central revolving body stator is made of an integral SS304 stainless steel pipe instead of the original combination of carbon steel base layer and inner surface copper stacking; during specific manufacturing, the SS304 stainless steel pipe needs to meet the requirements of GB/T8163-;
s2, primary test: carrying out size and quality inspection on the stainless steel pipe; specifically, whether the outer diameter, the out-of-roundness, the wall thickness and the like of the steel pipe meet requirements or not is checked, and whether quality defects such as pits and cracks exist or not is checked;
s3, blanking: sawing a stainless steel pipe according to the drawing and the machining amount; the allowance of the cut for sawing the stainless steel pipe is 10-15 mm;
s4, turning: processing the stainless steel pipe according to the drawing design and the surface roughness requirement; the method specifically comprises the following steps: roughly turning the inner circle, the outer circle and the end face of the stator, roughly turning the sealing groove and the oil duct on the inner surface of the stator, reserving a fine grinding allowance during processing, processing each oil hole and each threaded hole, finally changing a grinding head, processing the inner surface of the stator, the sealing groove and the oil duct, and requiring that the surface roughness Ra is less than or equal to 1.6 um;
s5, secondary inspection: inspecting the size and the surface roughness of the processed stator; specifically checking whether each processing dimension of the stator meets the requirement of a drawing or not, wherein the surface roughness Ra of the inner surface sealing groove, the oil duct and the contact surface of the inner surface sealing groove, the oil duct and the rotor is less than or equal to 1.6 um;
s6, surface nitriding treatment: and performing ion nitriding treatment on the stator subjected to secondary inspection to improve the surface hardness and the wear resistance, wherein the surface hardness value of the workpiece is required to reach 220-296HV, and the process parameters are as follows: interpolar voltage 520-550V, N2And H2The mixing ratio is 1: 3, the furnace pressure is 240-260Pa, the ion nitriding temperature is 420 ℃, and the heat preservation time is 6 h.
The stator is remanufactured by adopting a manufacturing process of stainless steel and ion nitriding treatment, the traditional design of a carbon steel base layer and copper pile is cancelled, the manufacturing cost is similar to the repairing cost of the traditional stator, but the manufacturing process is simpler, the manufacturing difficulty is lower, the corrosion resistance and the wear resistance are better, the subsequent repairing process is simpler and the repairing cost is lower.
Further, as shown in fig. 2 and 4, the repairing process of the central revolving body rotor comprises the following steps:
s1, cleaning: gasoline or alcohol is adopted to carry out degreasing and decontamination treatment on the central revolving body rotor, and the surface is not allowed to be rusted and dirty;
s2, chromium stripping: carrying out chromium stripping treatment on the chromium coating which falls off or has pockmarks; before chromium stripping, carrying out acid pickling treatment, etching the rotor in a conventional hydrochloric acid 1:1 solution, then carrying out alkali neutralization treatment and water washing, and repeating for many times to avoid damaging the base material as much as possible until the chromium coating is completely removed; or a lathe is additionally provided with a grinding head and a soft grinding wheel rough grinding wheel for grinding to remove the chromium coating;
s3, primary test: detecting whether the surface of the rotor base material has cracks and pit defects or not, and measuring the abrasion loss;
s4, surface turning: according to the measured abrasion loss, turning the surface of the rotor by using a lathe to remove pickling pits and grinding marks; the coaxiality is strictly ensured during processing, the surface processing depth is slightly lower than the maximum abrasion loss, and the processed surface has no grinding mark;
s5, surfacing of the wear-resistant welding wire: manufacturing a plurality of round wooden plugs, plugging the passage holes on the surface of the rotor to prevent the passage holes from being plugged during surfacing, so that deviation is generated between the subsequent re-drilling and the original position, and performing hardfacing on the surfaces of the rotors by using a wear-resistant welding wire; during overlaying, submerged arc welding is used, and the welding process parameters are as follows: uniformly heating the rotor to 300 ℃ before welding, wherein the welding material is stellite 225B, the diameter is 4mm, the welding flux is SJ101, the specification is 10-60 meshes, direct current reverse connection is adopted, the current is 360-400A, the voltage is 30-34V, the speed is 50-60cm/min, the rotating speed is 0.65-0.75r/min, and the heat preservation is needed for 1h after welding;
s6, rough machining: carrying out surface turning on the rotor subjected to surfacing by using a lathe; rough turning and finish turning are carried out, and finish grinding allowance is reserved during processing, wherein the surface roughness Ra is less than or equal to 3.2 um;
s7, finishing: carrying out fine grinding treatment on the surfaces of the rotors by using a grinding machine;
s8, secondary inspection: inspecting the size and the surface roughness of the processed rotor; specifically checking whether each machining size of the rotor meets the requirements of a drawing or not, wherein the roughness Ra of the outer circumferential surface is less than or equal to 0.2 um;
s9, surface nitriding treatment: performing surface nitriding treatment on the inspected rotor to improve the surface hardness and the wear resistance, wherein the excircle surface hardness value of the workpiece is required to reach 800-1000HV, and the process parameters are as follows: interpolar voltage 520-550V, N2And H2The mixing ratio is 1: 3, the furnace pressure is 240-260Pa, the ion nitriding temperature is 560 ℃, and the heat preservation time is 8 h.
Compared with the old surface chromium plating repair process, the ion nitriding process adopted by the invention is more green, environment-friendly and energy-saving, has better corrosion resistance and lower cost.
The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all equivalent structures made by using the contents of the present specification and the drawings can be directly or indirectly applied to other related technical fields, and are within the scope of the present invention.
Claims (8)
1. A remanufacturing process of a central revolving body of a shield tunneling machine is characterized by comprising a manufacturing process of a central revolving body stator, and comprises the following steps:
s1, material preparation: the remanufactured central revolving body stator is made of an integral stainless steel pipe instead of the original combination of a carbon steel base layer and copper pile on the inner surface;
s2, primary test: carrying out size and quality inspection on the stainless steel pipe;
s3, blanking: sawing a stainless steel pipe according to the drawing and the machining amount;
s4, turning: processing the stainless steel pipe according to the drawing design and the surface roughness requirement;
s5, secondary inspection: inspecting the size and the surface roughness of the processed stator;
s6, surface nitriding treatment: and carrying out ion nitriding treatment on the stator subjected to secondary inspection.
2. The remanufacturing process of a shield tunneling machine center rotor of claim 1 further comprising a repair process of the center rotor of rotation comprising the steps of:
s1, cleaning: carrying out degreasing and decontamination treatment on the central revolving body rotor by adopting gasoline or alcohol;
s2, chromium stripping: carrying out chromium stripping treatment on the chromium coating which falls off or has pockmarks;
s3, primary test: detecting whether the surface of the rotor base material has cracks and pit defects or not, and measuring the abrasion loss;
s4, surface turning: according to the measured abrasion loss, turning the surface of the rotor by using a lathe to remove the abrasion mark;
s5, surfacing of the wear-resistant welding wire: manufacturing a plurality of round wooden plugs, plugging the passage holes on the surface of the rotor, and performing wear-resistant surfacing on the surface of the rotor by using a wear-resistant welding wire;
s6, rough machining: carrying out surface turning on the rotor subjected to surfacing by using a lathe;
s7, finishing: carrying out fine grinding treatment on the surfaces of the rotors by using a grinding machine;
s8, secondary inspection: inspecting the size and the surface roughness of the processed rotor;
s9, surface nitriding treatment: and carrying out surface nitriding treatment on the rotor subjected to secondary inspection.
3. The remanufacturing process of a shield tunneling machine center revolving body of claim 1, wherein the stainless steel tube is an SS304 stainless steel tube.
4. The remanufacturing process of a shield tunneling machine center revolving body according to claim 1, wherein in S3, the cut allowance of the stainless steel pipe saw is 10-15 mm.
5. The shield tunneling machine center revolving body remanufacturing process of claim 1, wherein in S6, when the stator is subjected to ion nitriding treatment, process parameters are as follows: interpolar voltage 520-550V, N2And H2The mixing ratio is 1: 3, the furnace pressure is 240-260Pa, the ion nitriding temperature is 420 ℃, and the heat preservation time is 6 h.
6. The remanufacturing process of a shield tunneling machine center revolving body according to claim 2, wherein in S2, the specific operation of the chromium stripping treatment is: the rotor was etched in a hydrochloric acid solution, subjected to alkali neutralization treatment and water washing until the chromium plating layer was completely removed.
7. The remanufacturing process of a shield tunneling machine center revolving body according to claim 2, wherein in S5, the surfacing welding adopts submerged arc welding, and welding process parameters are as follows: the rotor is uniformly heated to 300 ℃ before welding, welding materials are Stellite 225B, the diameter is 4mm, welding flux is SJ101, the specification is 10-60 meshes, direct current reverse connection is adopted, the current is 360-plus 400A, the voltage is 30-34V, the speed is 50-60cm/min, the rotating speed is 0.65-0.75r/min, and the heat preservation is carried out for 1h after welding.
8. The remanufacturing process of a shield tunneling machine center revolving body according to claim 2, wherein in S9, when ion nitriding is performed on the rotor, the process parameters are as follows: interpolar voltage 520-550V, N2And H2The mixing ratio is 1: 3, the furnace pressure is 240-260Pa, the ion nitriding temperature is 560 ℃, and the heat preservation time is 8 h.
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| CN202210280864.8A CN114682999B (en) | 2022-03-21 | 2022-03-21 | Remanufacturing process for central revolving body of shield tunneling machine |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2006021983A1 (en) * | 2004-08-23 | 2006-03-02 | Kabushiki Kaisha Toshiba | Method and equipment for repairing rotor |
| CN105695924A (en) * | 2016-03-18 | 2016-06-22 | 常州大学 | Preparation method for nitrogen-bearing austenite stainless steel |
| CN110883495A (en) * | 2019-11-21 | 2020-03-17 | 浙江翰德圣智能再制造技术有限公司 | Online repair process for rotary valve rotor sealing surface |
| CN113388802A (en) * | 2021-05-28 | 2021-09-14 | 上海交通大学 | Ion nitriding method for improving wear-resisting and corrosion-resisting properties of martensitic stainless steel |
-
2022
- 2022-03-21 CN CN202210280864.8A patent/CN114682999B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2006021983A1 (en) * | 2004-08-23 | 2006-03-02 | Kabushiki Kaisha Toshiba | Method and equipment for repairing rotor |
| CN105695924A (en) * | 2016-03-18 | 2016-06-22 | 常州大学 | Preparation method for nitrogen-bearing austenite stainless steel |
| CN110883495A (en) * | 2019-11-21 | 2020-03-17 | 浙江翰德圣智能再制造技术有限公司 | Online repair process for rotary valve rotor sealing surface |
| CN113388802A (en) * | 2021-05-28 | 2021-09-14 | 上海交通大学 | Ion nitriding method for improving wear-resisting and corrosion-resisting properties of martensitic stainless steel |
Non-Patent Citations (1)
| Title |
|---|
| 朱英伟;郑立波;刘景华;: "盾构中心回转体结构及修复技术", 建筑机械化, no. 10 * |
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