A method for repairing the central area of ​​the cutterhead of a shield machine

Abstract

The present invention belongs to the technical field of shield machines, and specifically relates to a method for repairing the central area of ​​a shield machine cutterhead. The method for repairing the central area of ​​a shield machine cutterhead includes: repair preparation; repairing water injection nozzles and mud foam injection holes; repairing welded cutters; repairing replaceable scraper blade holders; and repairing cutter boxes and panels. The beneficial effect of the present invention is that the method for repairing the central area of ​​a shield machine cutterhead of the present invention can repair the central area of ​​a shield machine cutterhead in a tunnel by repair preparation, repairing water injection nozzles and mud foam injection holes, repairing welded cutters, repairing scraper blade holders, and repairing cutter boxes and panels, thereby avoiding ground well drilling and saving costs.

Description

Technical Field

[0001] The invention belongs to the technical field of shield machines, and in particular relates to a method for repairing the central area of ​​a shield machine cutter head. Background Art

[0002] Shield machines are mostly used in underground tunnel construction. During the construction process, the tunnel geology is complex and most of the strata are composite, that is, soft rock on the entire section, soft rock on the top and hard rock on the bottom, and hard rock on the entire section alternately. During the excavation process, the cutterhead, as one of the key components of the shield machine, plays the role of excavating the strata, supporting the heading face, and stirring the slag. Its working conditions are extremely harsh and the force is complex. It is the main component of the shield machine for inspection and maintenance. The quality of the cutterhead will directly affect whether the shield construction can proceed smoothly.

[0003] When the center area of ​​the shield machine cutterhead is severely worn, it is necessary to repair the damaged tool box, cutterhead panel, cutterhead wear plate, foam injection port, injection hole protection knife, wear detection knife, cutterhead water spray port, damaged welded scraper, replaceable scraper base, cutterhead spokes and the foam inside the spokes and water supply pipelines in the center area.

[0004] However, the existing shield machine cutterhead repair mostly adopts the method of digging wells on the ground to repair the shield machine cutterhead, which has high construction costs and complex processes, and seriously affects the construction period. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for repairing the central area of ​​a shield machine cutter head to solve the above technical problems.

[0006] In order to solve the above technical problems, the present invention provides a method for repairing the central area of ​​the shield machine cutter head, including: repair preparation; repairing the water injection nozzle and mud foam injection hole; repairing the welding type tool; repairing the replaceable scraper seat; repairing the tool box and panel.

[0007] Furthermore, the repair preparation includes: freezing the tunnel face; excavating a working space, excavating a repair studio in the central area in front of the cutterhead that at least covers the cutterhead wear area to provide the necessary working space for cutterhead repair; and setting up scaffolding.

[0008] Furthermore, the repair preparation also includes: ventilation from the tunnel to the warehouse and ventilation from the ground to the warehouse; wherein the ventilation from the tunnel to the warehouse includes: after the warehouse door is opened, the air in the warehouse is ventilated and replaced by a blower through the working channel, and the ventilation time should be no less than 30 min; After the personnel enter the soil bin, a fan is set up in the bin for continuous ventilation; the ventilation point can be set on the upper part of the cutter head; the ground ventilation to the bin includes: by drilling holes in the ground, inserting at least two seamless steel pipes between two rows of freezing holes to ventilate the working space, one of which is the air inlet pipe and the other is the exhaust pipe; after the chute is installed at the seamless steel pipe on the ground, the axial flow fan is inserted into the chute for ventilation.

[0009] Furthermore, the calculation method for the actual fan air volume required in the warehouse and working space includes:

[0010] Calculate air volume based on breathing and welding: Q 1=( q × N + q d × N d )× ɑ ;in q —The amount of fresh air required per person, take 3 m 3 / min ; q d —The amount of fresh air required for each welding machine is 50 m ³ / min ; N — Maximum number of people working on the job; N d —Number of welding machines working simultaneously; ɑ —Safety factor, take 1.2.

[0011] Calculate the air volume according to the minimum allowable wind speed: Q 2= v × A ;in v —Minimum permitted wind speed; A —Internal cross-sectional area.

[0012] Calculate the air volume based on the gas concentration not exceeding the limit: Q 3= g w / C ;in g w —Gas outflow speed, take 2 m ³ / min ; C —The safe gas concentration is 0.01.

[0013] The actual fan air volume required in the warehouse and working space is calculated as follows: Q = Max ( Q 1, Q 2, Q3) / [(1- β ) L / 100 ];in β - The air leakage coefficient of 100-meter air duct is 0.03; L —The maximum length of the ventilation duct from the ground to the warehouse.

[0014] Further, Q = Q 洞 + Q 地 ;in Q The actual fan air volume required in the warehouse and working space; Q 洞 The air volume of the fan that ventilates from the tunnel to the warehouse; Q 地 Adjust the air volume of the ventilation fan from the ground to the warehouse; and adjust the air humidity in the working space Q 洞 and Q 地 When the humidity of the working space is high, Q 洞 Turn down, Q 地 Increase until the air humidity in the working space meets the design requirements; when Q 地 When the air humidity in the working space still does not meet the design requirements when the air volume is adjusted to the designed maximum, the air dehumidification device in the warehouse is turned on; the calculation formula for the working time of the air dehumidification device is: ; In the above formula, is the working time of the air dehumidification device, in units of min ; For the time Q 地 The humidity of the working space when the air volume is adjusted to the maximum design volume, in units of g / m 3 ; is the required humidity in the working space, in units of g / m 3 ; It is the dehumidification speed of the air dehumidification device when it is working, in units of g / min ; is the volume of the working space, in units of m 3 .

[0015] Furthermore, the repair of the water injection nozzles and the mud foam injection holes includes: inspecting several water injection nozzles and several mud foam injection holes, confirming the degree of wear, counting the original parts that need to be replaced, and removing the worn original parts; removing and installing the worn water injection nozzles and mud foam injection holes, sealing the water injection nozzles and mud foam injection holes with a blocking plate, and using a trial tool to connect the air pipe to perform a pressure resistance test.

[0016] Furthermore, the repairing of the welding type cutting tools includes: marking and cutting off a number of worn welding type cutting tools, and using new cutting tools for positioning, preheating, welding, and heat preservation.

[0017] Furthermore, the repair of the replaceable scraper holder includes: marking and cutting off the worn scraper holder, removing the wear detection knife, using a new scraper holder for welding and blade back welding installation and wear detection tool installation, and using tooling to perform a pressure test.

[0018] Furthermore, the repairing of the cutter box and panel includes: marking and removing the cutter box to be repaired; repairing the wear at the center of the cutter disc; repairing the wear at the center of each spoke; repairing the wear at the panel; installing a new cutter box; and inspecting the cutter disc.

[0019] Furthermore, the marking and removal of the knife box that needs to be repaired include: finding a reference point on the rear side of the central quadruple knife box, marking the position of the knife box, and welding a number of seven-shaped plates; marking the original double knife box, welding a number of seven-shaped plates on each double knife box, and welding a number of seven-shaped plates in the direction of the earth warehouse; marking the original single-edge knife box, welding a number of seven-shaped plates on each single-edge knife box, welding a number of lifting ears in the direction of the earth warehouse and hanging a hand winch; and removing the marked quadruple knife box, the original double knife box, and the original single-edge knife box, and transporting them outside the earth warehouse using a hand winch.

[0020] Furthermore, the repairing of the center wear of the cutter disc includes: detecting the amount of wear on the center of the cutter disc; planing the worn area on the center of the cutter disc; positioning, preheating, welding, heat-insulating, and performing flaw detection tests on the newly manufactured center steel plate of the cutter disc.

[0021] Furthermore, repairing the worn areas at the center of each spoke includes: measuring the worn areas of each spoke; cutting new plates according to the measured data, cutting and grinding the steel plates at the worn areas; transporting the new plates to the front of the cutter head for positioning, preheating, welding, insulation, and NDT testing.

[0022] Furthermore, the repairing of the worn parts of the panels includes: measuring the data of each worn panel; cutting the plate according to the measured data, cutting off the worn parts of the original worn panels, transporting them out of the soil bin, and welding new steel plates; positioning and installing the new cutter head panel wear-resistant plate; and panel flaw detection.

[0023] The beneficial effect of the present invention is that the shield machine cutter head center area repair method of the present invention can repair the shield machine cutter head center area in the tunnel through repair preparation, repair water injection nozzles, mud foam injection holes, repair welding tools, repair scraper blade holders, repair tool boxes and panels, avoid ground well opening and save costs.

[0024] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention are realized and obtained by the structures particularly pointed out in the description and the drawings.

[0025] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0027] Figure 1 and Figure 2 is a schematic diagram of single disc wear of the present invention;

[0028] Figure 3 It is the excavation working space of the shield machine cutter head center area repair method of the present invention;

[0029] Figure 4 Schematic diagram of ventilation in the working space of the shield machine cutterhead center area repair method of the present invention;

[0030] Figure 5 Schematic diagram of ventilation points in the soil bin direction of the shield machine cutterhead center area repair method of the present invention;

[0031] Figure 6 Schematic diagram of ventilation points in the ring direction of the shield machine cutter head center area repair method of the present invention;

[0032] Figure 7 Schematic diagram of ventilation facilities for the shield machine cutterhead center area repair method of the present invention;

[0033] Figure 8 It is a schematic diagram of ground ventilation points of the shield machine cutterhead center area repair method of the present invention;

[0034] Figure 9It is a schematic diagram of the fan installation of the shield machine cutter head center area repair method of the present invention;

[0035] Figure 10 This is a schematic diagram of the locations of the mud foam injection holes in the shield machine cutter head center area repair method of the present invention;

[0036] Figure 11 It is a schematic diagram of the position of the welding cutter in the shield machine cutter head center area repair method of the present invention;

[0037] Figure 12 It is a schematic diagram of the position of the replaceable scraper blade holder of the shield machine cutter head center area repair method of the present invention;

[0038] Figure 13 This is a schematic diagram of the positions of the cutter box and panel to be repaired in the shield machine cutter head center area repair method of the present invention;

[0039] Figure 14 This is a schematic diagram of the 7-shaped plate welding of the shield machine cutter head center area repair method of the present invention;

[0040] Figure 15 Schematic diagram of cutting the center steel plate of the cutter head of the shield machine cutter head in the method for repairing the center area of ​​the cutter head of the present invention;

[0041] Figure 16 It is a spoke schematic diagram of the shield machine cutterhead center area repair method of the present invention;

[0042] Figure 17 It is a schematic diagram of the installation and transportation of the cutter box of the shield machine cutter head central area repair method of the present invention. DETAILED DESCRIPTION

[0043] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0044] like Figure 1 and Figure 2 As shown, the center of the cutter disc is more severely worn, and the wear depth in the cutter boxes 1-16 is 20-150 mm The main strata in a certain area are strongly weathered granite and sandy soil. The center area of ​​the shield machine cutterhead needs to be repaired inside the tunnel. Example

[0045] This embodiment provides a method for repairing the central area of ​​a shield machine cutterhead, including: repair preparation; repairing water injection nozzles and mud foam injection holes; repairing welding cutters; repairing scraper blade holders; and repairing cutter boxes and panels.

[0046] In this embodiment, the repair preparation mainly includes:

[0047] Before freezing the tunnel face, the driving internal gear oil, internal and external peripheral cooling water must be discharged and collected, the debris in the working space of the bin must be cleaned up, and the freezing effect of the tunnel face must be checked. Operations can only be carried out after the operating conditions are met;

[0048] Excavation of working space, such as Figure 3 As shown, excavate the working space, excavate a repair studio in the center area in front of the cutter head that at least covers the cutter head wear area, and provide the necessary working space for cutter head repair; it can be 3.5 high m 、Width 3.5 m 、Shenzhen 1 m The actual size of the "square" restoration studio will be adjusted according to the situation after opening;

[0049] The dirt inside the center of the cutter head and the dirt on the cutter head surface must be cleaned to check the wear of the pipeline and find the maintenance reference point;

[0050] Set up scaffolding within the working area and secure it in place.

[0051] In this embodiment, preferably, the method for repairing the central area of ​​the shield machine cutter head further includes ventilation from the tunnel into the chamber and ventilation from the ground into the chamber.

[0052] like Figure 4 As shown, the ventilation from the tunnel to the warehouse includes:

[0053] After the door is opened, use the blower to ventilate and replace the air in the warehouse through the working channel. The ventilation time should be no less than 30 min Safety officers carry portable hazardous gas detectors to monitor the gas composition within the warehouse. Ventilate the warehouse and monitor the gas levels in real time during operations. If any abnormality is detected, such as exceeding the specified range, personnel must evacuate immediately and the warehouse door must be closed. Personnel within the excavation warehouse must be evacuated, ventilation must be increased, and operations can only resume after the gas levels within the warehouse meet standards.

[0054] like Figure 5 、 Figure 6 and Figure 7 As shown, after personnel enter the soil warehouse and working space through the man warehouse, a fan is set up in the man warehouse for continuous ventilation. φ 650 mm The ventilation facilities can ensure the ventilation of soil bin working environment. The ventilation point can be set on the top of the cutter head.

[0055] The ground ventilation in the warehouse includes:

[0056] By drilling holes in the ground, such as Figure 8 As shown, it can be B Freeze holes and C Two seamless steel pipes are installed between the freezing holes for ventilation, one of which is the air inlet pipe and the other is the exhaust pipe. After the chute is installed at the ground seamless steel pipe, the diameter can be but not limited to φ 450 mm The axial flow fan is inserted into the chute for ventilation. φ 450 mmx 200 mm , use foam glue to seal the gap (see Figure 9 ).

[0057] This embodiment also provides a method for calculating the actual required fan air volume in the warehouse and the working space, which includes:

[0058] Calculate air volume based on breathing and welding Q 1. Calculate the air volume according to the minimum allowable wind speed Q 2. Calculate the air volume based on the gas concentration not exceeding the limit Q 3;

[0059] Pick Q 1. Q 2. Q 3, and taking into account the air leakage from the ground to the ventilation duct in the warehouse, the actual required fan air volume is calculated.

[0060] Specifically:

[0061] Calculate air volume based on breathing and welding:

[0062] Q 1=( q × N + q d × N d )× ɑ ;in

[0063] q —The amount of fresh air required per person, take 3 m 3 / min ;

[0064] q d —The amount of fresh air required for each welding machine is 50 m ³ / min ;

[0065] N — Maximum number of people working on the job;

[0066] N d —Number of welding machines working simultaneously;

[0067] ɑ —Safety factor, take 1.2.

[0068] Calculate the air volume according to the minimum allowable wind speed:

[0069] Q 2= v × A ;in

[0070] v —Minimum permitted wind speed;

[0071] A —Internal cross-sectional area.

[0072] Calculate the air volume based on the gas concentration not exceeding the limit:

[0073] Q 3= g w / C ;in

[0074] g w —Gas outflow speed, take 2 m ³ / min ;

[0075] C —The safe gas concentration is 0.01.

[0076] The actual fan air volume required in the warehouse and working space is calculated as follows:

[0077] Q = Max ( Q 1, Q 2, Q 3) / [(1- β ) L / 100 ];in

[0078] β - The air leakage coefficient of 100-meter air duct is 0.03;

[0079] L —The maximum length of the ventilation duct from the ground to the warehouse.

[0080] In a specific application scenario: according to the damage of the cutter box and the repair process and quality requirements of the cutter, a 3.4 high m 、Width 3.5 m, depth 0.9 m In order to meet the ventilation needs of the limited working space of the "door-shaped" restoration studio, the actual fan air volume required in the warehouse and working space is calculated as follows:

[0081] Q 1=( q × N + q d × N d )× ɑ =(3×5+50×2)×1.2=138 m 3 / min ;in q Take 3 m 3 / min ; q d Take 50 m ³ / min ; N Take 5; N d Take 2; ɑ Take 1.2.

[0082] Q 2= v × A =9×44.1=396.9 m ³ / min ;in v Take 9 m / min ; A Take 44.1 m 2 .

[0083] Q 3= g w / C =2 / 0.01=200 m ³ / min ;in g w Take 2 m ³ / min ; C Take 0.01.

[0084] The actual required fan air volume is calculated as follows:

[0085] Q = Max ( Q 1, Q 2, Q 3) / [(1- β )L / 100 ]=396.9 / (1-0.03) 0.3 =400.9 m ³ / min ;in β Take 0.03; L Take 30 according to working conditions m .

[0086] In this embodiment, the simultaneous implementation of both tunnel ventilation and ground ventilation is based on the consideration that the excavation workspace involves freezing the soil. As the temperature within the workspace rises during operation, the soil will melt to a certain extent, increasing the humidity within the workspace and affecting welding quality. Therefore, ground ventilation can quickly replace the humidity within the workspace, bringing it back to the level of surface working conditions. Furthermore, if only ground ventilation is used, multiple bottom ventilation pipes would be required, which is costly to install, and inserting multiple pipes into the soil can compromise the freezing effect, creating a risk. Therefore, in this embodiment, the simultaneous implementation of both tunnel ventilation and ground ventilation is preferred.

[0087] In this embodiment, Q = Q 洞 + Q 地 ;in Q The actual fan air volume required in the warehouse and working space; Q 洞 The air volume of the fan that ventilates from the tunnel to the warehouse; Q 地 Adjust the air volume of the ventilation fan from the ground to the warehouse; and adjust the air humidity in the working space Q 洞 and Q 地 When the humidity of the working space is high, Q 洞 Turn down, Q 地 Increase until the air humidity in the working space meets the design requirements; when Q 地 When the air humidity in the working space still does not meet the design requirements when the air volume is adjusted to the designed maximum, the air dehumidification device in the warehouse is turned on; the calculation formula for the working time of the air dehumidification device is: ; In the above formula, is the working time of the air dehumidification device, in units of min ; For the time Q 地 The humidity of the working space when the air volume is adjusted to the maximum design volume, in units of g / m 3 ; is the required humidity in the working space, in units of g / m 3 ; It is the dehumidification speed of the air dehumidification device when it is working, in units of g / min ; is the volume of the working space, in units of m 3 .

[0088] In this embodiment, the humidity of the ground ventilation to the warehouse is lower than the humidity of the tunnel ventilation to the warehouse, and the warehouse and the working space actually require a certain amount of fan air volume. Therefore, when it is detected that the humidity in the working space is high, the fan is adjusted down. Q 洞 , increase Q 地 To improve the dehumidification efficiency of the working space; when Q 地 When the air volume is adjusted to the maximum designed volume, if it is detected that the humidity of the working space is still higher than the required humidity standard, the dehumidification device will be used to assist in dehumidification. At this time, the working time of the dehumidification device is Calculated, where By detecting the relative humidity in the working space and converting it through the formula, By converting the required humidity of the working space into a formula, the dehumidification speed of the air dehumidifier when working can be obtained. The data obtained during the dehumidification test of the air dehumidification device is calculated and the average value is taken.

[0089] In this embodiment, the repair of the water injection nozzles and the mud foam injection holes includes: inspecting several water injection nozzles and several mud foam injection holes, confirming the degree of wear, counting the original parts that need to be replaced, and removing the worn original parts; removing and installing the worn water injection nozzles and mud foam injection holes, sealing the water injection nozzles and mud foam injection holes with a blocking plate, and connecting the trial tool to the air pipe for a pressure test.

[0090] In the optional application scenario, take the mud foam injection hole as an example, such as Figure 10 As shown, the rear side of the cutter head can be removed according to the center position KF 1 / KF 2 / KF 3. After removing the injection port blanking plate, remove the bolts of the injection port seamless pipe flange and take out the seamless steel pipe; use an industrial water pipe to insert into the flange to dredge the pipe; use a carbon planer to plane off a circle around the injection nozzle; after installing the new nozzle or injection port in place, grind a circle of welds and fill them; after installation is completed,M 16 x Install with 6010.9 grade bolts; install the original seamless steel pipe in place and install the sealing ring; perform 5 bar Holding pressure 5 min stress test.

[0091] In this embodiment, the repairing of the welding type cutting tools includes: marking and removing a number of worn welding type cutting tools, and using new cutting tools for positioning, preheating, welding, and heat preservation.

[0092] In optional application scenarios, such as Figure 11 As shown, the circled area is the location of the welding scraper. After the original welding tool is removed, position the new tool and use a level ruler to measure the welding; the welding tool groove is a double-sided groove, 10 mm , next 15 mm .

[0093] like Figure 12 As shown, the circle is a replaceable scraper holder. In this embodiment, the repair of the replaceable scraper holder includes: marking and cutting off the worn scraper holder, removing the wear detection knife, using a new scraper holder for welding and blade back welding installation and wear detection tool installation, and using tooling to perform a pressure test.

[0094] Specifically, the dismantling steps are as follows: Use a steel ruler or angle square to measure and mark the original replaceable scraper holder, and use a carbon planer to plane off the replaceable scraper holder and the anti-block in turn; the scraper holder installation steps are: Position the new scraper according to the previous scraper holder positioning mark, and use a spirit level to level it. After positioning, weld and weld the anti-block into position; take dehumidification and fume exhaust measures in the welding area and ensure smooth ventilation; check the on-site welding groove before welding. If there is rust, it needs to be polished; before welding, check the groove on both sides of the groove 100 mm Use a drying gun for preheating within the range, and control the preheating temperature at 120-150 degrees before welding to remove moisture from the surface of the steel plate; use small current, thin layer welding, multi-layer and multi-pass welding; grind the spatter and slag on the weld surface; use a heating plate to heat the base material during low-temperature welding in the warehouse to prevent cracks in the weld; after the weld is completed, the weld should be cooled slowly, and the base material should be wrapped with insulation cotton (heating plate) to ensure that the interlayer temperature is not lower than 150 degrees.

[0095] like Figure 13 As shown, in this embodiment, the repair of the tool box and panel includes: marking and removing the tool box to be repaired; repairing the wear at the center of the tool disc; repairing the wear at the center of each spoke; repairing the wear at the panel; installing a new tool box; and inspecting the tool disc.

[0096] In this embodiment, preferably, the marking and removal of the knife box to be repaired include: finding a reference point on the rear side of the central quadruple knife box, marking the position of the knife box, and welding a number of seven-shaped plates; marking the original double knife box, welding a number of seven-shaped plates on each double knife box, and welding a number of seven-shaped plates in the direction of the earth warehouse; marking the original single-edge knife box, welding a number of seven-shaped plates on each single-edge knife box, welding a number of lifting ears in the direction of the earth warehouse and hanging a hand winch; and removing the marked quadruple knife box, the original double knife box, and the original single-edge knife box, and transporting them outside the earth warehouse using a hand winch.

[0097] In a practical application, there are 10 wear knife boxes, including 1 center quadruple knife box, 5 center double knife boxes, and 4 single knife boxes near the center. Figure 14 As shown, the rear end of the tool box is used as the reference surface (less worn), and four 7-shaped plates are welded on the back to mark the position of the tool box. The tool box is then planed and the 7-shaped positioning plates are retained. When the tool box is worn to the point where a new tool cannot be installed, it is cut off and replaced with a new one. 10 welds are cut off (4 on the front and 6 on the back). When cutting off the 6 positioning block welds on the back, be careful not to damage the positioning block body, which will affect the positioning of the tool box. After the cutting is completed, pull forward (towards the palm face) to remove the old tool box. Clean the residue and burrs on the cut area, cut out 20 weld grooves, and then use an angle grinder for precise grinding to ensure that the groove surface is flat and the weld leg size is accurate. The specific weld leg size is: 15 for the 4 front welds mm , 4 welds 15 in the length direction of the rear tool box mm , 2 welds in the width direction of the tool box 10 mm .

[0098] In this embodiment, the repairing of the center wear of the cutter disc includes: detecting the amount of wear on the center of the cutter disc; planing the worn area on the center of the cutter disc; positioning, preheating, welding, insulating, and performing flaw detection tests on the newly manufactured center steel plate of the cutter disc.

[0099] In one application scenario, the center steel plate box of the cutter disc has inconsistent thickness on the four sides. The spoke thickness is trimmed according to the maximum wear depth of a single spoke (the thickness of the spoke with small local wear can be adjusted according to the actual situation. The trimming thickness of the single-edge hob is trimmed according to the designed thickness of the cutter disc) and then cut. After cutting, it is polished and iron slag and stains are removed. Figure 15 As shown, the material is cut into four sections, the groove is cut and then sent to the site for positioning and welding.

[0100] The center steel plate transportation method of the cutter head: After cutting off the center steel plates in sequence, transport 4 center steel plates through the center triangle opening or the center block position. The 4 steel plates are welded with lifting rings. Use the original lifting point above the soil bin and use 1 TThe hand chain hoist transports the 4 steel plates to the lock chamber and introduces them into the shield body in sequence; the 4 new cutter head center steel plates are transported to the soil chamber through the lock chamber, and 1 T The hand hoists are alternately transported to the rear side of the cutter head center, and the four center steel plates are dragged to the center of the cutter head by manpower.

[0101] Installation method: Use an angle grinder to grind the cut position flat, remove oil and residue, install the four steel plates to the center of the original cutter head, and perform positioning welding.

[0102] Inspection requirements: 100% magnetic particle inspection is used, and ultrasonic inspection is required for repaired grooves to ensure that the weld reaches 80% of the groove depth.

[0103] Process requirements: Before welding, the groove and both sides are 100 mm Use a drying gun to heat within the range to remove moisture from the steel plate. The preheating temperature should not be lower than 100°C. Use specified flux-cored wire for welding. GFL -71 Ni , wire diameter Φ 1.2 mm ;use CO 2 gas as protective gas, gas flow rate 15-20 L / min ; Bottom welding current 220-260 A , welding voltage 27-29 V ; Filling cap welding welding current 240-260 A , welding voltage 28-30 V ;Connection speed 13-20 cm / min ; Welding adopts multi-layer and multi-pass welding, and the thickness of single-layer single-pass weld does not exceed 5 mm ; Control the interlayer temperature of welding ≤220℃; During welding, after the knife box is positioned, check the gap between the knife box and the knife disc. If the gap is greater than 5 mm When welding, the gap between the cutter box and the cutter disc must be filled with thin iron sheets before welding. The thin iron sheets must be lower than the root of the weld. After the weld is completed or the welding is interrupted, it must be immediately covered with insulation cotton to slow down the cooling. If cracks are found during the welding process, they must be cleaned and polished in time before welding, provided that the technology is approved. Cover with insulation cotton with good thermal insulation performance, and at least 40~80 mm Thick insulation cotton, let it cool slowly, and remove the insulation measures after it reaches room temperature; clean the spatter slag on the weld surface; after welding is completed h After that, the welds are inspected according to the corresponding requirements, and all welds are 100% MT Flaw detection and meet MT ( GB / T26952-2011) Level 1 qualified.

[0104] In this embodiment, optionally, repairing the worn area at the center of each spoke includes: measuring the worn area of ​​each spoke; cutting the new plate according to the measured data, and cutting and grinding the steel plate at the worn area; transporting the new plate to the front of the cutter disc for positioning, preheating, welding, insulation, and NDT testing.

[0105] In one application scenario, such as Figure 16 As shown, according to the 6 spokes of blade wear, according to the maximum wear depth t =150 mm (If the local wear is small, the length will be adjusted according to the actual situation on site) and cut off. The length will be determined according to the actual wear range on site.

[0106] Cutting of spokes on the cutter disc: trim the spoke thickness according to the maximum wear depth on a single spoke (the thickness of the spokes can be adjusted according to the actual situation if the local wear is small. The thickness of the single-edged hob is trimmed according to the thickness of the cutter disc design. The length is determined according to the wear range and welding requirements. Grind the cut surface flat and remove oil and residue. According to the size of the spokes to be cut, use a 9 cm thick Q 355 B For materials of the same size under the steel plate, the welding surface shall be grooved at 45 degrees on both sides and the part requiring overhead welding shall be grooved on one side with a depth of 43 mm. The worn parts of the 6 spokes shall be cut (cut off in sequence, in the order of 1-4, 2-5, 3-6). After cutting, the surface shall be polished and smoothed to remove oil stains and residues.

[0107] Repair of the spokes: Use a welding torch to t =90 mm Overlap the steel plate with the original cutter disc spokes, use steel ruler, angle square, level ruler and other tools to measure, ensure the straightness, height and flatness of the overlapped spoke steel plate, the operation sequence is 1-4, 2-5, 3-6 spokes; according to the size of the good Q 355 B The steel plate is overlapped with the original cutter disc spoke, and is measured with tools such as steel ruler and angle square to ensure the straightness, height and flatness of the overlapped spoke steel plate. After confirmation, positioning is carried out and flaw detection is carried out after welding is completed (flaw detection requirements: 100% magnetic particle inspection is used, and ultrasonic testing is required for repaired grooves to ensure that the weld reaches 80% of the groove depth); positioning welding is carried out after confirmation, and the surface oil and residue are cleaned after welding is completed.

[0108] Workpiece groove requirements: The welding surface shall have a 45-degree double-sided groove (depth 43 mm) and the part requiring overhead welding shall adopt a single-sided groove (depth 88 mm).

[0109] Process requirements: 30° on both sides of the groove before welding mmGrind within the range to remove rust, oil and oxide scale on the surface; before welding, grind the groove and both sides 100 mm Use a drying gun to heat within the range to remove moisture from the steel plate. The preheating temperature should not be lower than 100°C. Use specified flux-cored wire for welding. GFL -71 Ni , wire diameter Φ 1.2 mm ;use CO 2 gas as protective gas, gas flow rate 15-20 L / min ; Bottom welding current 220-260 A , welding voltage 27-29 V ; Filling cap welding welding current 240-260 A , welding voltage 28-30 V ;Connection speed 13-20 cm / min ; Welding adopts multi-layer and multi-pass welding, and the thickness of single-layer single-pass weld does not exceed 5 mm ; Control the interlayer temperature of welding ≤ 220℃;; During welding, after the knife box is positioned, check the gap between the knife box and the knife disc. The gap is greater than 5 mm When welding, the gap between the cutter box and the cutter disc must be filled with thin iron sheets before welding. The thin iron sheets must be lower than the root of the weld. After the weld is completed or the welding is interrupted, it must be immediately covered with insulation cotton to slow down the cooling. If cracks are found during the welding process, they must be cleaned and polished in time before welding, provided that the technology is approved. Cover with insulation cotton with good thermal insulation performance, and at least 40~80 mm Thick insulation cotton, let it cool slowly, and remove the insulation measures after it reaches room temperature; clean the spatter slag on the weld surface; after welding is completed h After that, the welds are inspected according to the corresponding requirements, and all welds are 100% MT Flaw detection and meet MT ( GB / T 26952-2011) Level 1 qualified.

[0110] Delivery method: Cutting according to the wear size of 6 spokes, the size shall not exceed the gate warehouse φ 650 mm ; The newly made spoke plate is carried out through the lock chamber, and the heavy objects are welded through the lifting lugs above the soil chamber. The newly made plate is lifted to the center position, and the plate is dragged to the front at the center triangle area or the center knife box position. According to the actual situation on site, the lifting lugs are welded above the knife disc and 1 is hung. T Hand chain hoist.

[0111] In this embodiment, optionally, the repairing of the worn parts of the panels includes: measuring the data of each worn panel; cutting the plate according to the measured data, cutting off the worn parts of the original worn panels, transporting them out of the soil bin, and welding new steel plates; positioning and installing the new cutter head panel wear-resistant plate; and panel flaw detection.

[0112] In one application scenario, the worn cutter head panel can be removed by arranging 2 welders and 2 general workers to enter the soil bin, use a protractor and a steel ruler to measure the size, and remove all the remaining parts according to the actual worn area, and cut off the panels with 2-5 and 3-6 wear in turn.

[0113] Repair of the cutter head panel: Grind the position where the original panel was cut off, clean the oil and debris; transport the new panel into the earth bin and drag it to the front of the cutter head; use a spirit level to position and weld the new panel surface.

[0114] The workpiece form is 20 mm The groove is fillet welded and 100% magnetic particle inspection is adopted.

[0115] Process requirements: 30° on both sides of the groove before welding mm Grind within the range to remove rust, oil and oxide scale on the surface; before welding, grind the groove and both sides 100 mm Use a drying gun to heat within the range to remove moisture from the steel plate. The preheating temperature should not be lower than 100°C. Use specified flux-cored wire for welding. GFL -71 Ni , wire diameter Φ 1.2 mm ;use CO 2 gas as protective gas, gas flow rate 15-20 L / min ; Bottom welding current 220-260 A , welding voltage 27-29 V ; Filling cap welding welding current 240-260 A , welding voltage 28-30 V ;Connection speed 13-20 cm / min ; Welding adopts multi-layer and multi-pass welding, and the thickness of single-layer single-pass weld does not exceed 5 mm ; Control the interlayer temperature of welding ≤220℃; During welding, after the knife box is positioned, check the gap between the knife box and the knife disc. If the gap is greater than 5 mmWhen welding, the gap between the cutter box and the cutter disc must be filled with thin iron sheets before welding. The thin iron sheets must be lower than the root of the weld. After the weld is completed or the welding is interrupted, it must be immediately covered with insulation cotton to slow down the cooling. If cracks are found during the welding process, they must be cleaned and polished in time before welding, provided that the technology is approved. Cover with insulation cotton with good thermal insulation performance, and at least 40~80 mm Thick insulation cotton, let it cool slowly, and remove the insulation measures after it reaches room temperature; clean the spatter slag on the weld surface; after welding is completed h After that, the welds are inspected according to the corresponding requirements, and all welds are 100% MT Flaw detection and meet MT ( GB / T 26952-2011) Level 1 qualified.

[0116] In this embodiment, repairing the tool box and panel also includes removing and installing the tool disc wear plate.

[0117] In this embodiment, repairing the knife box and panel also includes knife box installation.

[0118] In one application scenario, when installing the tool box: transport the new tool box to the excavation chamber in front of the cutterhead, place the tool box in the box slot from the soil facing side to the soil bin, first push the tool box backward (towards the soil bin) to the bottom, adjust the direction to ensure that the four sides of the tool box are in contact with the 6 positioning blocks at the same time, and realize the two-degree-of-freedom positioning of the tool box front and back; then move the tool box in the direction of the inserted steel strips and press it, and at the same time check and confirm that the contact surface with the 6 positioning blocks fits, and then use the pre-prepared δ =3-5 mm Steel plate (processed in advance to be thin at the front and thick at the back), using the pre-welded "7-shaped plate", and the adult's arm push and compact it to achieve the precise positioning of the tool box in four degrees of freedom, up and down, left and right; preliminary spot welding is performed in the four weld directions at the front of the tool box, and it is installed using the pre-prepared hob cutter die, and is checked using measuring tools (ruler, square and special tooling). When the tooling is fixed, the lower end face is flush with the cutter head ring beam surface, and the radial direction is 8 mm , and perform full welding after confirmation.

[0119] New tool box welding: Preheat before welding. Due to the high humidity in the tunnel, the preheating temperature must be between 120℃ and 150℃. When pausing welding, cover with insulation cotton to prevent the weld from cooling quickly. Preheat again before welding again. Ceramic heating plates are preferred for preheating. If flame heating is used, good ventilation must be maintained. Welding is performed using non-inert gas shielded arc welding (135) with a shielding gas of 80%. Ar +20% CO 2 The recommended welding wire for mixed gas is 71 NiSolid welding wire is used for welding. Welding should be done layer by layer in multiple times to ensure that there is no fault in the welding. The welding sequence requirements of the hob cutter box are: ① The weld between the top plate of the cutter box and the cutter head steel structure; ② The weld between the top plate of the cutter box and the hob cutter box; ③ The circumferential weld on the front of the hob cutter box.

[0120] Tool box transportation method: During the material transportation process, the tool box is transported by hanging a hand chain hoist at 6 lifting points above the soil bin. t Single chain hoist (see Figure 16 ); The cutter box enters the tunnel face through the angle between the spokes. The tunnel face needs to be excavated to 3050 mm The working space is large enough to accommodate the tool box.

[0121] Tool box installation process requirements: the welding area should be well dehumidified and smoke-exhausted, and the ventilation should be smooth; the groove before welding and the sides of the groove should be 30 mm Grind within the range to remove rust, oil and oxide scale on the surface; before welding, grind the groove and both sides 100 mm Use a drying gun to heat within the range to remove moisture from the steel plate. The preheating temperature should not be lower than 100°C. Use specified flux-cored wire for welding. GFL -71 Ni , wire diameter Φ 1.2 mm ;use CO 2 gas as protective gas, gas flow rate 15-20 L / min ; Bottom welding current 220-260 A , welding voltage 27-29 V ; Filling cap welding welding current 240-260 A , welding voltage 28-30 V ;Connection speed 13-20 cm / min ; Welding adopts multi-layer and multi-pass welding, and the thickness of single-layer single-pass weld does not exceed 5 mm ; Control the interlayer temperature of welding ≤220℃; When welding, after the knife box is positioned, check the gap between the knife box and the knife disc. If the gap is greater than 5 mm When welding, the gap between the cutter box and the cutter disc must be filled with thin iron sheets before welding. The thin iron sheets must be lower than the root of the weld. After the weld is completed or the welding is interrupted, it must be immediately covered with insulation cotton to slow down the cooling. If cracks are found during the welding process, they must be cleaned and polished in time before welding, provided that the technology is approved. Cover with insulation cotton with good thermal insulation performance, and at least 40~80 mm Thick insulation cotton, let it cool slowly, and remove the insulation measures after it reaches room temperature; clean the spatter slag on the weld surface; after welding is completed h After that, the welds are inspected according to the corresponding requirements, and all welds are 100% MT Flaw detection and meet MT ( GB / T 26952-2011) Level 1 qualified; 100% adopted MT flaw detection.

[0122] The various devices selected in this application (components whose specific structures are not described) are all universal standard parts or components known to those skilled in the art, and their structures and principles can be known to those skilled in the art through technical manuals or conventional experimental methods.

[0123] In the description of the embodiments of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection.

[0124] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0125] With the above-described preferred embodiments of the present invention as a guide, and with reference to the above description, relevant personnel are fully capable of making various changes and modifications without departing from the technical scope of this invention. The technical scope of this invention is not limited to the contents of the specification and must be determined according to the scope of the claims.

Claims

1. A method for repairing the central area of ​​a shield machine cutterhead, characterized in that: include: Restoration preparation; Repair water injection nozzles and mud foam injection holes; Repair welding type knives; Repair the replaceable scraper blade holder; Repair knife box and panel; The repair preparation includes: Palm face freezing; Excavate a working space, and excavate a repair workshop in the center area in front of the cutterhead that at least covers the cutterhead wear area to provide the necessary working space for cutterhead repair; erecting scaffolding; The repair preparation also includes: ventilation from the tunnel to the warehouse and ventilation from the ground to the warehouse; The ventilation from the tunnel to the bunker includes: after the bunker door is opened, the air in the bunker is ventilated and replaced by a blower through the working channel, and the ventilation time should be no less than 30 minutes; after the personnel enter the soil bunker, a fan is set up in the personnel bunker for continuous ventilation; the ventilation point can be set on the upper part of the cutterhead; The ground ventilation of the warehouse includes: drilling holes in the ground, inserting at least two seamless steel pipes between two rows of freezing holes into the working space for ventilation, one of which is an air inlet pipe and the other is an exhaust pipe; after installing a chute straight through at the ground seamless steel pipe, inserting an axial flow fan into the chute straight through for ventilation.

2. The shield machine cutterhead center area repair method according to claim 1, characterized in that: The calculation methods for the actual fan air volume required in the warehouse and working space include: Calculate air volume based on breathing and welding: Q1=(q×N+q d ×N d ) × ɑ; among them q—the amount of fresh air required per person, taking 3m 3 / min; q d —The amount of fresh air required for each welding machine is 50m 3 / min; N—maximum number of people working on the job; N d —Number of welding machines working simultaneously; ɑ—safety factor, take 1.2; Calculate the air volume based on the minimum allowable wind speed: Q2=v×A; v—minimum allowed wind speed; A—internal cross-sectional area; Calculate the air volume based on the gas concentration not exceeding the limit: Q3=g w / C; where g w —Gas outflow velocity, take 2m 3 / min; C—gas safety concentration, taken as 0.01; The actual fan air volume required in the warehouse and working space is calculated as follows: Q = Max (Q1, Q2, Q3) / [(1-β) L / 100 ];in β—air leakage coefficient per 100 meters of air duct, take 0.03; L—The maximum length of the ventilation duct from the ground to the warehouse.

3. The shield machine cutterhead center area repair method according to claim 1, characterized in that: Q=Q 洞 +Q 地 ;in Q is the actual fan air volume required in the warehouse and working space; Q 洞 Q is the air volume of the fan for ventilation from the tunnel to the warehouse; 地 The air volume of the fan for ventilation from the ground to the warehouse; as well as Adjust Q according to the air humidity in the working space 洞 and Q 地 The size of When the air humidity in the working space is high, Q 洞 Turn down, Q 地 Increase it until the air humidity in the working space meets the design requirements; When Q 地 When the air volume is adjusted to the designed maximum, if the humidity in the working space still does not meet the design requirements, turn on the air dehumidification device in the warehouse; in The calculation formula of the dehumidification time of the air dehumidification device is: ； In the above formula, The dehumidification time of the air dehumidification device, in minutes; For Q 地 The humidity of the working space when the air volume is adjusted to the maximum design value, in g / m 3 ; The required moisture content of the working space, in g / m 3 ; It is the dehumidification rate of the air dehumidification device when it is working, in g / min; is the volume of the working space, in m 3 .

4. The shield machine cutterhead center area repair method according to claim 1, characterized in that: The repairing water injection nozzle and mud foam injection hole includes: Check several water injection nozzles and several mud foam injection holes to confirm the degree of wear, count the parts that need to be replaced, and remove the worn parts; Remove and install the worn water injection nozzles and mud foam injection holes, block them with a blocking plate, and connect the test tool to the air pipe for a pressure test; and The repairing of welding type cutting tools comprises: marking a number of worn welding type cutting tools and then cutting them off, and using new cutting tools to perform positioning, preheating, welding, and heat preservation; The repair of the replaceable scraper holder includes: marking and cutting off the worn scraper holder, removing the wear detection knife, using a new scraper holder for welding and blade back welding installation and wear detection tool installation, and using tooling to perform a pressure test.

5. The method for repairing the central area of ​​the shield machine cutter head according to claim 1, characterized in that: The repair tool box and panel include: Mark and remove knife boxes that need repair; Repair the wear on the center of the cutter head; Repair the worn area at the center of each spoke; Repair panel wear; Install a new knife box; Cutter head flaw detection.

6. The shield machine cutterhead center area repair method according to claim 5, characterized in that: The marking and removal of the tool box for repair includes: Find the reference point on the back of the center quadruple tool box, mark the tool box position, and weld several seven-shaped plates; Mark the original double knife boxes, weld several seven-shaped plates on each double knife box, and weld several seven-shaped plates in the direction of the earth warehouse; Mark the original single-edge knife boxes, weld several seven-shaped plates on each single-edge knife box, weld several lifting ears in the direction of the earth warehouse and hang a hand hoist; and Remove the marked quadruple knife box, the original double knife box, and the original single-edged knife box, and use a hand hoist to transport them out of the soil bin.

7. The method for repairing the central area of ​​the cutter head of a shield machine according to claim 5, characterized in that: The repairing of the center wear of the cutter head includes: Detect the wear of the center of the cutter head; Remove the worn area in the center of the cutter head; The newly manufactured cutter head center steel plate is positioned, preheated, welded, insulated, and subjected to flaw detection tests in sequence.

8. The method for repairing the central area of ​​the cutter head of a shield machine according to claim 5, characterized in that: Repairing center wear on each spoke includes: Measure the wear on each spoke; Cut the new plates according to the measured data, and cut and grind the worn parts; Transporting new panels to the front of the cutterhead for positioning, preheating, welding, insulation, and flaw detection testing; and The repair panel wear part includes: Measure the data of each worn panel; Cut the plate according to the measured data, remove the worn parts of the original panel, transport them out of the earth warehouse, and weld the new steel plate; Position and install the newly made cutter head panel wear plate; Panel flaw detection.

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