CN116276336A - Method for polishing top surface of welded rail of vertical-grinding steel rail aluminothermic welding head - Google Patents
Method for polishing top surface of welded rail of vertical-grinding steel rail aluminothermic welding head Download PDFInfo
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- 238000003466 welding Methods 0.000 title claims abstract description 86
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B1/00—Processes of grinding or polishing; Use of auxiliary equipment in connection with such processes
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B49/00—Measuring or gauging equipment for controlling the feed movement of the grinding tool or work; Arrangements of indicating or measuring equipment, e.g. for indicating the start of the grinding operation
- B24B49/02—Measuring or gauging equipment for controlling the feed movement of the grinding tool or work; Arrangements of indicating or measuring equipment, e.g. for indicating the start of the grinding operation according to the instantaneous size and required size of the workpiece acted upon, the measuring or gauging being continuous or intermittent
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B9/00—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor
- B24B9/02—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor characterised by a special design with respect to properties of materials specific to articles to be ground
- B24B9/04—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor characterised by a special design with respect to properties of materials specific to articles to be ground of metal, e.g. skate blades
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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
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/10—Greenhouse gas [GHG] capture, material saving, heat recovery or other energy efficient measures, e.g. motor control, characterised by manufacturing processes, e.g. for rolling metal or metal working
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Abstract
The invention provides a method for polishing the top surface of a welded rail by a vertical grinding steel rail aluminothermic welding head; wherein two steel rails to be welded are a rail 1 with relatively light vertical grinding degree or a new rail is a rail 2 with relatively serious vertical grinding degree, and the thermite welded front rail 1 and the rail 2 are aligned in a rail bottom alignment mode; the post-welding polishing method comprises the following steps: I. and (3) measuring the arch starting quantity of the welded joint, determining the polishing length and depth of the rail 1, III, polishing the joint and the near-end steel rail of the rail 1, IV, polishing the far-end steel rail of the rail 1, V, and determining the polishing effect and VI of the rail 1 and the polishing rail 2. The polishing method provides post-welding polishing data support for the aluminothermic welding heads under different vertical polishing conditions, and has important significance for reducing operation difficulty, standardizing field operation, improving post-welding joint quality and improving smoothness of the steel rail tread.
Description
Technical Field
The invention belongs to the technical field of steel rail welding, and particularly relates to a method for polishing a welded rail top surface of a vertical grinding steel rail aluminothermic welding head.
Background
The thermite welding technology of steel rail is one of the important welding technologies of railway seamless rail welding, and is applied to the work of joint, frog, locking welding, existing line stress relief, broken rail rush repair, daily rail change and the like. When the existing line is subjected to damage treatment, in order to adapt to the operation mode of the skylight point, an insert welding method is generally adopted, namely: the position of the rail where the flaw is found is sawed off and then inserted into a section of pre-assembled rail, and thermite welding is carried out on the two ends of the rail respectively, so that two new thermite welding heads are generated. With the continuous increase of new railway lines and the increase of the operation time of the existing lines in China in recent years, the number of the thermit welding heads is increasing. The statistics prove that the total existing line injury treatment in 2022 is welded with about 20 ten thousand heads, wherein 17 ten thousand heads are thermite welded, and the existing line injury treatment is dominant.
Joint polishing is the last procedure of the thermite welding technology of the steel rail, and plays a vital role in joint quality, service life and track smoothness. Ren Jinlei according to the requirements of the line design speed v of more than 160km/h on the flatness and the surface unevenness of the thermit welding head, polishing schemes including polishing length and polishing depth are designed for different original states of the joint, polishing parameter indexes are quantized, unnecessary grinding of steel rails is reduced, and the scheme is preliminarily applied (Ren Jinlei, song Hongtu and Gao Songfu. Design of scheme of five-four-wire polishing scheme of thermit welding joint of high-speed railway steel rails [ J ]. Railway technical supervision, 2021, 49 (8): 48-55). The scheme aims at post-welding polishing of standard profile steel rail thermite welding joints, namely the steel rail tread and working edges at two sides of the joints are not worn and have no height difference.
In fact, during the emergency repair of existing damaged lines, the welding of the rail occurs frequently due to vertical grinding (abrasion of the rail in the height direction): or the steel rail on the existing line is vertically ground, and the matched rail during insertion welding is a new rail; or the steel rail on the existing line is not vertically ground, and the matched rail during insertion welding is a vertically ground rail; or the steel rail and the matched rail on the existing line have vertical abrasion but different vertical abrasion amounts. The inventor conducts investigation on the part of railway bureaus in China, and the result shows that: the rail distribution abrasion phenomenon used in the on-line insert welding is common at present. Taking a welding cycle plan of a certain working section as an example: 96 welding aluminum thermal welding joints are recorded in the week, most of insertion rails used for welding have vertical grinding, wherein the number of steel rail welding joints with the vertical grinding of 1mm is 19, and the welding ratio is 20%; the number of the steel rail welding joints with the vertical grinding of 2mm is 35, and the ratio is 36%; the number of welded joints of the steel rail with the vertical grinding of 3mm is 28, and the ratio is 29%. The inventor also researches the vertical grinding condition of the steel rail on the existing line in the domestic part, and the result shows that: the amount of rail sagging is more common at 0-5mm, with sagging at 0-3mm being the most common. The post-weld grinding scheme proposed by Ren Jinlei et al for standard profile rail thermite welding joints is clearly not applicable to the vertical rail welds that are common in practice. At present, special process specifications for post-welding polishing of a vertical grinding steel rail welding joint are hardly available in domestic road bureau and station sections, and the experience of field operators is mainly relied on. Because of various conditions of vertically grinding the steel rail, the post-welding polishing operation difficulty is high, a unified operation method is not available, and the quality of the post-welding joint is difficult to guarantee when the on-site skylight is salvaged.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention provides a method for polishing the top surface of a welded rail of a vertical grinding steel rail aluminum thermal welding head based on the prior investigation data and the requirements in related standards and specifications. The method provides post-welding polishing data support for the aluminothermic welding heads under different vertical polishing conditions, and has important significance for reducing operation difficulty, standardizing field operation, improving post-welding joint quality and improving smoothness of the steel rail tread.
In order to achieve the aim of the invention, the invention adopts the following technical scheme:
a polishing method for a welded rail top surface of a vertical-grinding steel rail aluminum thermal welding head; wherein two steel rails to be welded are a rail 1 with relatively light vertical grinding degree or a new rail is a rail 2 with relatively serious vertical grinding degree, and the thermite welded front rail 1 and the rail 2 are aligned in a rail bottom alignment mode; the post-welding polishing method comprises the following steps:
I. post-weld joint camber measurement
Placing a 1m notch leveling ruler on the tread of the steel rail, aligning a 0 scale mark with the center of the welding line, and measuring the arch camber a of one side of the rail 1 by adopting a feeler gauge or a clearance gauge, wherein the unit is mm/m;
II, determining the polishing length and depth of the rail 1
If a is more than 0 and less than or equal to 0.4mm/m, calculating the polishing depth H of the rail 1 by adopting a formula (1) -1, and calculating the polishing length L of the rail 1 by adopting a formula (1) -2:
H＝h 0 (1)-1，
if a > 0.4mm/m, calculating the polishing depth H of the track 1 by using the formula (2) -1, and calculating the polishing length L of the track 1 by using the formula (2) -2:
H＝h 0 +Q(a-0.4) (2)-1，
in the above formulas (1) -1, (1) -2, (2) -1 and (2) -2,
h 0 for welding the height difference at the head of the front rail 1 and the rail 2, in mm,
q is a constant, q=1m,
a f the unit mm/m is 0.1 is less than or equal to a for the target flatness of the joint and the near end after finishing polishing the set rail 1 f ≤0.4mm/m，
t is the distal rail grade of rail 1, and t=0.4 mm/m;
in the formulas (1) -2 and (2) -2,
length L of grinding for the proximal end of rail 1 Near-to-near ，
Or->
Length L of grinding for the distal end of rail 1 Far distance ；
III, polishing joint and rail 1 near end steel rail
Firstly, according to the calculated polishing depth H and the proximal polishing length L Near-to-near Marking the near end polishing terminal points respectively, and polishing the weld center and the near end of the rail 1 by using a polisherThe steel rail reaches a near end polishing end point;
IV. grinding rail 1 distal rail
Firstly, according to the calculated far end polishing length L Far distance Marking a distal polishing end point, and polishing from the proximal polishing end point to the distal rail 1 to the distal polishing end point by using a polisher;
v. determining the grinding effect of the rail 1
During and after polishing, continuously measuring the flatness of the welding line and the rail 1 by adopting a 1m flat ruler or an SRC electronic flat ruler until the flatness meeting the standard requirement is achieved;
VI grinding track 2
The rail 2 is polished conventionally until the flatness required by the standard is met.
In said step I, the actual measured value of said camber a only remains one decimal place, e.g. 0.1mm/m, 0.2mm/m, 0.3mm/m, 0.4mm/m, 0.5mm/m, 0.6mm/m, 0.7mm/m, 0.8mm/m, 0.9mm/m, etc.
In the polishing method, the two steel rails to be welded are divided into the rail 1 and the rail 2 according to the relative vertical polishing degree, the rail 1 is a new rail with lower relative vertical polishing degree, and the rail 2 is a rail with more serious relative vertical polishing degree. Therefore, after thermite welding by adopting a rail bottom alignment mode, the heights of the two side rails 1 and the rail 2 of the joint tread have a height difference, and the rail 1 is higher than the rail 2, as shown in fig. 4.
Preferably, in the steps III and IV, polishing is performed by using a profile sander or a peripheral sander.
Preferably, in steps V and VI, the standard is TB/T1632.1-2014, rail weld part 1: general technical conditions.
Specific requirements in the above criteria are: the low joint should not appear in the length range of 1m of the working surface of the rail welding joint rail head. When the line design speed v is less than or equal to 160km/h, a is less than or equal to 0.1 1 ≤0.4，0≤b 1 B is more than or equal to 0.3 or less than or equal to 0 2 ≤0.3。(a 1 Indicating the flatness of the top surface of the rail head, b 1 、b 2 Represents the flatness of the working edge of the side, b 1 Taking positive values to widen the gauge, b 2 Taking a positive value means that the gauge is reduced,in mm/m). The polishing depth of the parent metal is preferably less than 0.5mm. After the welding joint is subjected to appearance finishing, the surface unevenness of the rail top surface within a range of 1m taking the welding seam as the center is required to meet the following conditions: no more than 0.2mm in any 200mm section.
As a preferred embodiment, the step II, when h 0 When 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 4mm, 5mm or 6mm, and 0.1 mm/m.ltoreq.a.ltoreq.0.9 mm/m, the polishing length and depth of the rail 1 are determined according to the following table 1, otherwise the polishing length and depth of the rail 1 are calculated according to the formulas (1) -1 and (1) -2, or the formulas (2) -1 and (2) -2:
table 1 vertical grinding rail polishing quick table
When the total length of the grinding exceeds half the length of the rail 1 due to the excessively large height difference, the welding should be performed considering the off-line pre-arrangement or the pre-arrangement of the rails with small height difference.
In the present specification, the "existing line" refers to a concept of a railway line which is subjected to a certain amount of traffic and load with respect to a newly built line. The existing line is in an operation state, and the maintenance processing time is limited. The vertical grinding steel rail is a steel rail with a standard profile, and after the steel rail is in service for a period of time, certain abrasion exists at the tread part of the rail head of the steel rail along the height direction, and the vertical grinding steel rail is called as a vertical grinding steel rail.
In the specification, the thermite welding refers to a method of combining aluminum powder, ferric oxide powder, iron alloy and the like according to a certain proportion to form a thermite welding agent, igniting the thermite welding agent by using a high Wen Huochai, performing chemical reaction and metallurgical reaction to obtain molten steel and slag, injecting the high-temperature molten steel into a casting mold, and welding two sections of steel rails together. Thermite welding, so thermite welding is also known as cast welding. The main procedures of thermite welding are generally: preparing work, drying a steel rail, rust removal and decontamination, steel rail alignment, sand mold installation, fixture installation, box sealing, preheating, crucible flux preparation, reaction casting, mold removal, tumor pushing and polishing. The polishing method is the final step of the thermite welding process.
The joint polishing or the polishing joint refers to that the aluminum thermal welding joint and the base materials of steel rails on two sides are trimmed by using a polisher so that the surface quality of the aluminum thermal welding joint or the base materials of steel rails on two sides meets the standard requirement.
In the present specification, the "proximal end" or the "distal end" of the steel rail is the "proximal end" and the "distal end" is the "distal end" of the steel rail close to the center of the weld.
Drawings
The invention is further described below with reference to the accompanying drawings.
Fig. 1 shows that rails 1 and 2 are aligned in a rail bottom alignment in embodiment 1, wherein a: aligning the completed three-dimensional graph, B: a physical photograph.
The photograph of fig. 2 shows the sand mold loaded after the alignment of the rails 1 and 2 in example 1 is completed.
The photograph of fig. 3 shows the post-weld head rail foot in example 1.
Fig. 4 is a photograph showing the macroscopic state of the post-weld joint tread after completion of thermite weld nugget pushing in example 1.
Fig. 5 is a schematic view showing the measurement of the camber of a welded joint using a notch leveling ruler in example 1.
Fig. 6 shows a schematic illustration of the polishing of the weld seam and the rail 1 in example 1, wherein a: polishing by adopting an end face polishing machine, and B: and polishing by adopting a peripheral surface polisher.
Fig. 7 shows a schematic view of the polished steel rail in example 1, wherein the upper fold line is the overall trend of the tread of the steel rail: the point 1 is the polishing end point of one side of the rail 2, the point 0 is the center of the welding seam, the point 1 is the polishing end point of the near end of the rail 1, and the point 2 is the polishing end point of the far end of the rail 1.
The photograph of fig. 8 shows the two-sided rail centered on the weld head after finishing the grinding of example 1, wherein a: photograph taken from oblique side, B: photographs taken directly against the weld.
In each of the above figures, 1: a rail 1;2: and a rail 2.
Detailed Description
The invention is described below with reference to specific examples. It will be appreciated by those skilled in the art that these examples are for illustration of the invention only and are not intended to limit the scope of the invention in any way.
The experimental methods in the following examples are conventional methods unless otherwise specified. The raw materials, reagent materials and the like used in the examples described below are commercially available products unless otherwise specified.
In the following examples, ZTK-1 thermite welding materials (new materials technology Co., ltd. In iron, beijing) were used, the welding flux was T3, and the two welded rails were 60kg/m U Mn H, one of which was a new rail (rail 1) and the other was a vertically ground rail (rail 2), and the heights of rail 1 and rail 2 were 3mm,6mm and 9mm, respectively. The welding tool comprises a special preheating device, a sand mold clamp, alignment equipment, a rail sawing machine, a tumor pushing machine, a grinding machine and the like.
All welding technological parameters follow the specification in the thermite welding operation manual provided by manufacturers, and the reserved rail gap of the steel rail is 28-30 mm. The rail bottom alignment mode is adopted, and the profile difference does not exist between the steel rails to be welded at the two ends in the height direction, so that the standard profile sand mold can be adopted for welding.
In the rail alignment link, the arch starting quantity of the rails at the two sides is regulated to be 1.5-2 mm/m based on the rail bottom. The specific method comprises the following steps: a1 m straight ruler is arranged at the bottom corner of the rail, a 0 scale mark is positioned at the center of a rail gap, the heights of steel rails at two sides are adjusted by adopting special rail aligning devices such as an A-shaped aligning frame, an iron wedge or a rail jack, and the like, and a clearance gauge or a clearance gauge is adopted in the adjusting process to measure the arch rise until a set value is met.
And (5) installing and clamping the sand mold after the alignment of the steel rail is completed. The preheater support is arranged at one end of the rail 1, the height is 50mm, the pressure of oxygen gas for preheating is 0.3MPa, the pressure of propane gas is 0.1MPa, the height of the preheater is 50mm, the preheating time is 4min, the mould is removed for 6min30 s after casting is completed, and the mould is pushed for 8min30 s. The heights of base materials at two sides of the tread of the welded joint are different.
Example 1 method of polishing the top surface of a rail after thermite welding of rails 1 and 2 having a height difference of 3mm
When thermite welding, the rail 1 and the rail 2 are aligned in a rail bottom alignment mode, and a three-dimensional diagram and a physical diagram of the alignment are shown in fig. 1. And after the alignment of the steel rail is completed, clamping the sand mold, as shown in fig. 2. As can be seen from fig. 2, after the standard profile sand mold is clamped, the rail head tread of the rail 2 (vertically ground rail) is lower than the rail head tread of the rail 1 (new rail), but the sand mold is not inclined, and the rail bottom and the bottom plate are closely adhered well. The welded joint rail bottom is shown in fig. 3, and the welded joint rail bottom does not generate overflow flash. As shown in fig. 4, the welded joint tread has a height difference between the heights of the side rails 1 and 2, wherein the high rail 1 and the low rail 2. Post-weld grinding is performed according to the following steps
I. Post-weld joint camber measurement
As shown in FIG. 5, a 1m notch leveling ruler is arranged on the tread of the steel rail, the 0 scale mark is aligned with the center of the welding line, and the arch forming amount a of one side of the rail 1 is measured to be 0.4mm/m by adopting a feeler gauge or a clearance gauge.
II, determining the polishing length and depth of the rail 1
Since a=0.4 mm/m was measured, a was set f =0.4 mm/m, the polishing depth H of the rail 1 was calculated using formula (1) -1, and the polishing length L of the rail 1 was calculated using formula (1) -2:
H＝h 0 (1)-1，
wherein h is 0 The height difference of the rail heads of the welding front rail 1 and the rail 2 is in mm; where h is 0 ＝3mm，
Q is constant, q=1m;
a f the target joint and the proximal end flatness after finishing polishing are set for the track 1, and the unit is mm/m; where a f ＝0.4mm/m，
t is the distal rail grade of rail 1, and t=0.4 mm/m;
in the above-mentioned formula (1) -2,
length L of grinding for the proximal end of rail 1 Near-to-near ,
Length L of grinding for the distal end of rail 1 Far distance ；
Calculated, h=3mm, l Near-to-near ＝1m，L Far distance =7.5 m, total sanding length l=8.5 mm.
Looking up table 1, it can be quickly derived that: h=3mm, l Near-to-near ＝1m，L Far distance =7.5 m, total sanding length l=8.5 mm.
III, polishing joint and rail 1 near end steel rail
Firstly, according to the calculated polishing depth H and the proximal polishing length L Near-to-near Marking near end polishing end points respectively, and polishing weld center and weld center by using a profiling polisher or a peripheral polisher as shown in FIG. 6The near end rail of the rail 1 reaches a near end polishing terminal point;
IV. grinding rail 1 distal rail
Firstly, according to the calculated far end polishing length L Far distance Marking a polishing end point, and polishing from the proximal polishing end point to the distal polishing end point of the rail 1 to the distal polishing end point by using a profiling polisher or a peripheral polisher;
v. determining polishing effect
And in the polishing process and after polishing, a 1m straight ruler or an SRC electronic straight ruler is continuously adopted to measure the flatness of the welding line and the rail 1 until the requirements are met.
VI grinding of rail 2
The rail 2 is polished conventionally until the flatness required by the standard is met.
The schematic diagram of the steel rail and the overall trend of the tread of the steel rail after polishing are shown in fig. 7, and the two side steel rails centering on the welding head after polishing are shown in the photograph of fig. 8. As shown in fig. 7, the whole of the rail is represented by a certain amount of camber on both sides of the weld joint, and the rail on one side of the rail 1 (new rail) transits from the far end to the near end polishing end point with a certain gradient. Fig. 8 shows that the flatness of the rails 1 and 2 is good after finishing the sanding.
Example 2 polishing method of rail 1 and rail 2 thermite welded rail top surface with height difference of 6mm
Post-weld grinding was performed in the same manner as in example 1 except that in step I, the camber amount a of the rail 1 side was measured to be 0.3mm/m, and a was set f =0.3 mm/m, calculated using equations (1) -1 and (1) -2, h=6mm, l Near-to-near ＝1mm，L Far distance Total sanding length l=16 mm =15 mm. The same sanding parameters can also be obtained quickly by looking up table 1.
Example 3 polishing method of rail 1 and rail 2 thermite welded rail top surface with 9mm height difference
Post-weld grinding was performed in the same manner as in example 1 except that in step I, the camber amount a of the rail 1 side was measured to be 0.5mm/m, and a was set f =0.4 mm/m, using formula (2) -1 and formula (2) -2:
H＝h 0 +Q(a-0.4) (2)-1，
wherein h is 0 The height difference of the rail heads of the welding front rail 1 and the rail 2 is in mm; where h is 0 ＝9mm，
Q is constant, q=1m;
a f the target joint and the proximal end flatness after finishing polishing are set for the track 1, and the unit is mm/m; where a f ＝0.4mm/m，
t is the distal rail grade of rail 1, and t=0.4 mm/m;
Calculated, h=9.1 mm, l Near-to-near ＝1.25m，L Far distance 22.75m, total sanding length l=24 mm.
Because of the height difference h between the rail 1 and the rail 2 0 =9 mm, outside the ranges listed in table 1, and therefore the sanding parameters can only be calculated using the formula.
In a word, the invention provides a method for polishing the top surface of a welded rail by a vertical grinding steel rail aluminothermic welding head. The method provides post-welding polishing data support for the aluminothermic welding heads under different vertical polishing conditions, and has important significance for reducing operation difficulty, standardizing field operation, improving post-welding joint quality and improving smoothness of the steel rail tread.
Claims (4)
1. A method for polishing the top surface of a welded rail by a vertical grinding steel rail aluminum thermal welding head; wherein two steel rails to be welded are a rail 1 with relatively light vertical grinding degree or a new rail is a rail 2 with relatively serious vertical grinding degree, and the thermite welded front rail 1 and the rail 2 are aligned in a rail bottom alignment mode; the post-welding polishing method comprises the following steps:
I. post-weld joint camber measurement
Placing a 1m notch leveling ruler on the tread of the steel rail, aligning a 0 scale mark with the center of the welding line, and measuring the arch camber a of one side of the rail 1 by adopting a feeler gauge or a clearance gauge, wherein the unit is mm/m;
II, determining the polishing length and depth of the rail 1
If a is more than 0 and less than or equal to 0.4mm/m, calculating the polishing depth H of the rail 1 by adopting a formula (1) -1, and calculating the polishing length L of the rail 1 by adopting a formula (1) -2:
H＝h 0 (1)-1，
if a > 0.4mm/m, calculating the polishing depth H of the track 1 by using the formula (2) -1, and calculating the polishing length L of the track 1 by using the formula (2) -2:
H＝h 0 +Q(a-0.4) (2)-1，
in the above formulas (1) -1, (1) -2, (2) -1 and (2) -2,
h 0 for welding the height difference at the head of the front rail 1 and the rail 2, in mm,
q is a constant, q=1m,
a f the unit mm/m is 0.1 is less than or equal to a for the target flatness of the joint and the near end after finishing polishing the set rail 1 f ≤0.4mm/m，
t is the distal rail grade of rail 1, and t=0.4 mm/m;
in the formulas (1) -2 and (2) -2,
length L of grinding for the proximal end of rail 1 Near-to-near ，
Or->
Length L of grinding for the distal end of rail 1 Far distance ；
III, polishing joint and rail 1 near end steel rail
Firstly, according to the calculated polishing depth H and the proximal polishing length L Near-to-near Marking near-end polishing terminal points respectively, and polishing the weld joint center and the near-end steel rail of the rail 1 to the near-end polishing terminal points by using a polisher;
IV. grinding rail 1 distal rail
Firstly, according to the calculated far end polishing length L Far distance Marking a distal polishing end point, and polishing from the proximal polishing end point to the distal rail 1 to the distal polishing end point by using a polisher;
v. determining the grinding effect of the rail 1
During and after polishing, continuously measuring the flatness of the welding line and the rail 1 by adopting a 1m flat ruler or an SRC electronic flat ruler until the flatness meeting the standard requirement is achieved;
VI grinding track 2
The rail 2 is polished conventionally until the flatness required by the standard is met.
2. The polishing method according to claim 1, wherein in the steps III and IV, polishing is performed using a profile sander or a peripheral sander.
3. A grinding method according to claim 1 or 2, wherein in steps V and VI, the standard is TB/T1632.1-2014 "rail welded part 1: general technical conditions.
4. A sanding method as defined in any one of claims 1 to 3 wherein step II, when h 0 When =0.5 mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 4mm, 5mm or 6mm, and 0.1 mm/m.ltoreq.a.ltoreq.0.9 mm/m, the polishing length and depth of the rail 1 were determined according to the following tableThe degree, otherwise, the polishing length and depth of the rail 1 are calculated according to the formulas (1) -1 and (1) -2 or the formulas (2) -1 and (2) -2:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310365335.2A CN116276336A (en) | 2023-04-07 | 2023-04-07 | Method for polishing top surface of welded rail of vertical-grinding steel rail aluminothermic welding head |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310365335.2A CN116276336A (en) | 2023-04-07 | 2023-04-07 | Method for polishing top surface of welded rail of vertical-grinding steel rail aluminothermic welding head |
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| CN116276336A true CN116276336A (en) | 2023-06-23 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202310365335.2A Pending CN116276336A (en) | 2023-04-07 | 2023-04-07 | Method for polishing top surface of welded rail of vertical-grinding steel rail aluminothermic welding head |
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| Country | Link |
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| CN (1) | CN116276336A (en) |
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2023
- 2023-04-07 CN CN202310365335.2A patent/CN116276336A/en active Pending
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