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How to Solve Rail Joint Problems
Oct 06, 2021
Rail joint bolts are also called track bolts, fish bolts, which belong to fasteners for rail joint bars, rail joint bolts are used to fix the 2 rail fish plates onto 2 steel rails tracks. Sometimes, hexagon bolts can be replaced by railway fish bolts which can save labors.
Classification
According to the material, it is divided into ordinary joint bolts and high-strength joint bolts.
Ordinary bolts are made into a square head on the top surface of a semi-circular sphere; Grade 8.8 high-strength bolts are added with two rings of ribs on the top surface of the semi-circular sphere at the square head part to distinguish them from ordinary bolts; the top surface of the square head of 10.9 high-strength bolts is made into a flat frustum shape. Usually the length of the rail joint bolt is 150-170mm; the area immediately adjacent to the square head is made of an elliptical convex neck. When the rail joint is assembled, the convex neck enters the long round hole of the joint splint, which can prevent the bolt from idling when the nut is tightened. The high-strength nut used in conjunction with the high-strength bolt has a convex ring mark of 1mm in height and width on the 30° chamfered surface of the top.
Problems of rail joints
Rail joints are one of the three weak parts in the track structure. It is the main reason for the long-term troubles to improve the speed and quality of the line. It is the focus of the daily maintenance of the track maintenance department. The maintenance and repair work of the joints accounts for 60% of the track maintenance work. The most fundamental reason for the occurrence of rail joint problems is the discontinuity in the track structure and the unevenness of the rail surface in the rail joint, which leads to the generation of greater additional power between the wheel and the rail.
The excessively large additional dynamic effect promotes the development of discontinuity and irregularity and the increase of additional dynamic, and at the same time promotes the development of joint problems. In addition, improper maintenance methods will promote the occurrence and development of joint problems. Due to repeated ramming of the joint, the standard is not high, the formed joint ends are unevenly soft and hard, the rail seam is too large, the joint bolt torque is insufficient, the joint height, and the left and right teeth are misaligned. Under the impact of the train wheelset, the joint rail is caused. If there is block dropped from rail joints, the sleeper will crack and fail, and the rail splint damage will increase. As a result, the maintenance cycle of the joint is shortened, the labor intensity of the railway personnel is increased, and the unsafe factor is left to the railway transportation.
Remediation method
There are many causes of problems on rail joint bars, and its treatment should also be a comprehensive treatment.
We should start with the structure first, and ensure the smoothness of the track with the health of the structure. Dealing with any problem does not mean that today's dynamic detection says that it blindly mashes the pad in case of the height of the place is bad, or change the way in case the direction of the place is bad. As trains continue to speed up and equipment continue to improve, our operating methods will also change.
We should adopt the principle of careful inspection and repair to carefully investigate why the height is not good from many aspects. Is it because there are high and low teeth, rail scars and other damages, rubber pads collapse and fail, loose parts cause the rail to crawl and the rail gap becomes larger, because the empty hoist makes the ballast rounding failure. We should eliminate the above problems and replace with new ballast with better diameters.
Finally, tamping and eliminating the joint empty hanging plate can effectively control the occurrence and development of the joint high and low level triangle pits.
Poor direction: It is not that the direction is poor or the direction of the two rails is poor. Why is the poor direction caused by the spout, uneven fat edge of the rail, hard bending of the rail, poor gauge change rate, wrong left and right teeth and loose parts, nylon seats are damaged and failure, and the rubber pads are squeezed, resulting in false gauges and false track directions. We should start with these structural problems before rectifying and correcting the direction. Of course, our work must always implement the "safety first, prevention first" policy, and strictly implement the rule for "repair in the absence of train passing". Give full play to the efficiency of manpower and machinery in the repair rule as the standard of our daily operations. No construction will be carried out when train passing, and no train passing will be carried out when construction. Strictly "prevention first, combination of prevention and solve, repair and maintenance are same important" is the principle of railway maintenance work implemented in the operation, so that the train can run safely, smoothly and uninterrupted at the specified speed, and maximize the service life of the wagons.
Classification
According to the material, it is divided into ordinary joint bolts and high-strength joint bolts.
Ordinary bolts are made into a square head on the top surface of a semi-circular sphere; Grade 8.8 high-strength bolts are added with two rings of ribs on the top surface of the semi-circular sphere at the square head part to distinguish them from ordinary bolts; the top surface of the square head of 10.9 high-strength bolts is made into a flat frustum shape. Usually the length of the rail joint bolt is 150-170mm; the area immediately adjacent to the square head is made of an elliptical convex neck. When the rail joint is assembled, the convex neck enters the long round hole of the joint splint, which can prevent the bolt from idling when the nut is tightened. The high-strength nut used in conjunction with the high-strength bolt has a convex ring mark of 1mm in height and width on the 30° chamfered surface of the top.
Problems of rail joints
Rail joints are one of the three weak parts in the track structure. It is the main reason for the long-term troubles to improve the speed and quality of the line. It is the focus of the daily maintenance of the track maintenance department. The maintenance and repair work of the joints accounts for 60% of the track maintenance work. The most fundamental reason for the occurrence of rail joint problems is the discontinuity in the track structure and the unevenness of the rail surface in the rail joint, which leads to the generation of greater additional power between the wheel and the rail.
The excessively large additional dynamic effect promotes the development of discontinuity and irregularity and the increase of additional dynamic, and at the same time promotes the development of joint problems. In addition, improper maintenance methods will promote the occurrence and development of joint problems. Due to repeated ramming of the joint, the standard is not high, the formed joint ends are unevenly soft and hard, the rail seam is too large, the joint bolt torque is insufficient, the joint height, and the left and right teeth are misaligned. Under the impact of the train wheelset, the joint rail is caused. If there is block dropped from rail joints, the sleeper will crack and fail, and the rail splint damage will increase. As a result, the maintenance cycle of the joint is shortened, the labor intensity of the railway personnel is increased, and the unsafe factor is left to the railway transportation.
Remediation method
There are many causes of problems on rail joint bars, and its treatment should also be a comprehensive treatment.
We should start with the structure first, and ensure the smoothness of the track with the health of the structure. Dealing with any problem does not mean that today's dynamic detection says that it blindly mashes the pad in case of the height of the place is bad, or change the way in case the direction of the place is bad. As trains continue to speed up and equipment continue to improve, our operating methods will also change.
We should adopt the principle of careful inspection and repair to carefully investigate why the height is not good from many aspects. Is it because there are high and low teeth, rail scars and other damages, rubber pads collapse and fail, loose parts cause the rail to crawl and the rail gap becomes larger, because the empty hoist makes the ballast rounding failure. We should eliminate the above problems and replace with new ballast with better diameters.
Finally, tamping and eliminating the joint empty hanging plate can effectively control the occurrence and development of the joint high and low level triangle pits.
Poor direction: It is not that the direction is poor or the direction of the two rails is poor. Why is the poor direction caused by the spout, uneven fat edge of the rail, hard bending of the rail, poor gauge change rate, wrong left and right teeth and loose parts, nylon seats are damaged and failure, and the rubber pads are squeezed, resulting in false gauges and false track directions. We should start with these structural problems before rectifying and correcting the direction. Of course, our work must always implement the "safety first, prevention first" policy, and strictly implement the rule for "repair in the absence of train passing". Give full play to the efficiency of manpower and machinery in the repair rule as the standard of our daily operations. No construction will be carried out when train passing, and no train passing will be carried out when construction. Strictly "prevention first, combination of prevention and solve, repair and maintenance are same important" is the principle of railway maintenance work implemented in the operation, so that the train can run safely, smoothly and uninterrupted at the specified speed, and maximize the service life of the wagons.