1. Gnawing rail wheels reasons
Gnawing rail wheel carts caused by many reasons, some orbit, some wheel problems, but also due to deformation caused by the bridge.
(1) Wheel Problem
① wheel mounting position is not accurate, there are three tracks of eating.
a. The deviation is too large wheels. Wheel mounting the deviation is less than a predetermined level l/1000 (l is the length measured on the wheels), and a pair of wheels on the same axis to be opposite to the deflection direction, tracks or wheels inevitably nibbles.
b. Wheel vertical deviation is too large. The center line of the wheel end to form an angle with the vertical line, the wheel is in an inclined state. Wheel vertical deviation should not dry l/400, wheel vertical deviation is caused by gnawing track driving wheel and passive wheel independent.
c. Wheel spacing, ranging diagonal and two wheels on the same rail line adverse, can also cause the crane rail wheels bite.
② wheel machining errors caused by gnawing rail. Two wheel diameters ranging initiative will make both sides of the wheel speed is not the same, after traveling some distance, causing the body to go oblique, lateral movement occurs, resulting in the phenomenon of gnawing rail, which focused driven mechanism is particularly evident.
(2) orbit
Poor mounting rail carts, rail is not straight, would inevitably lead to gnaw rails. If two tracks relative elevation deviation is too large, the crane in the transverse movement during operation, resulting in eating the same side of two adjacent tracks of the rail head surface is not the same horizontal plane, when the operation of the crane to the track joint, the wheel will move laterally , which occurred in the phenomenon of gnawing rail, rail-top surface with oil, water, frost, which may make the car skid rails, body caused by gnawing away ramps rails bend of the track is too large, when exceeded the span of tolerance, would inevitably lead to the wheel rim friction with the track side.
(3) bridge deformation
Deformation will cause the wheels skew bridge and crane span changes, so that the level of the end beam bending, causing the wheel horizontal deflection, vertical deviation tolerance, causing the wheel nut rails.
(4) Transmission manufacturing error is too large
Traveling mechanism drive gear clearance ranging shaft key will cause loosening gnawing rail. For each driver operating agencies, when the motor speed difference is too large, adjust the tightness of different brake will cause the body to go diagonally occur gnawing rail.
2 gnawing rail inspection methods
Gnawing rail crane inspection methods phenomena are:
(A) by visual inspection will find a bright side rail traces of hair with a serious scar on traces, or bright spots on the inside rim of the wheel, you can conclude that gnawing crane rails.
(2) during operation of the crane in a short distance, between the wheel rim and the rail obvious change in the gap, the crane will bite rail.
(3) Crane in starting or braking, the vehicle ramp walk, twist, will cause the wheel nut rails.
3. Measures to prevent wheel bite rail
Focus respectively on the drive and driven operating agencies to prevent and improve the crane rail wheels gnawing approach should be different. Through careful examination, carefully adjusted to correct inaccurate wheels and track mounting, pay attention to operating agencies on both sides of each drive motor, brake and gear synchronization problem does not exist.
(A) restrict the bridge span L and K Tread ratio. Crane allow a certain freedom in the distortion, which allows the wheel flange and the rail lateral movement between a certain distance. The greater the distance, the more will bite rail, and with L / K on the ratio, the greater the ratio, the smaller freedom permitted skew, more prone to eating rail. It should take a small L / K value of the experience shows, L / K is not greater than 5 to 6:00 is more favorable.
(2) the operation of institutions such as the central drive wheel a total of four, including two for the Active Wheel, the initiative can be conical wheel tread (taper 1:10), and the large end of the cone inward installation, using convex top track, after several cranes will automatically adjust the direction of the swing, reducing the friction between wheel and rail.
(3) The side of the track and wheel flange lubrication methods to reduce operating friction, to reduce the wear of the wheels.
(4) Always check whether the deformation of the bridge, and promptly corrected to conform to the technical requirements, or can not fundamentally solve the problem of the wheel-rail gnawing diagonal, vertical and horizontal degrees of tolerance should be timely adjusted.
