Annexure 2.1
Method of Applying Adjustment at Front Tower of Tamping Machine on Curve
When the front tower of the tamping machine enters the curve, the rear tightening bogie is still on straight. Therefore, it experiences error because of the curvature and certain adjustments have to be applied at the front bogie to compensate the error due to curvature. Similar adjustments are also required when the tamping machine leaves the curve at other end.
The procedure for applying these adjustments as the machine enters or leaves the curves is explained below: -
(i) For a particular curve having length of transition 'L' and radius of circular curve 'R', pick up the maximum adjustment value 'Vm" from Table 1.(ii) Then from Table 2, pick up the adjustment value 'V 'for different positions of the front tower corresponding to the value 'Vm' as obtained in para (i) above.
(iii) As the front tower of the machine enters the curve at UA1 and negotiate along the transition curve, apply the adjustments equal to the value 'V' as obtained in para (ii) above, value varies from zero at UA1, to Vm at 20 metres distance from UA1 .
(iv) For remaining length of the transition curve i.e. 20 metres beyond UA1, till the front tower reaches location UE1,, uniform adjustment value equal to 'Vm' will be applied at the front tower.
(v) As soon as the front tower of the machine enters the circular curve at UE1,. apply adjusment of value 'V'obtained from the Table 2, ranging from Vm at location UE1, to zero at location of 20 metres distance beyond point UE1,
The adjustments explained in para (ii) to (v) above are to be applied in direction of outer rail of the curve, as indicated in Table 2.(vi) For remaining length of the curcular curve, the adjustment value will remain zero till the front tower reaches location UE2,.
(vii) As the front tower enters the transition curve at location UE2, apply adjustment value 'V' ranging from zero at UE2, to Vm at 20 metres distance beyond UE2, as obtained from Table 3.(viii) For remaining length of the transition curve at location 20 metres beyond UE2, till the front tower reaches location UA2, adjustment of value Vm will be applied.
(ix) When the front tower enters the straight track at location UA2; apply adjustment 'V', ranging from Vm
at UA2, to zero at 20 metres
distance from UA2, as obtained
from Table 3.The
adjustments explained in para (vii) to (ix) above are to be applied in
direction of inner rail of the curve as indicated in Table 3.