@article{(Open Science Index):https://publications.waset.org/pdf/8888,
	  title     = {Nonlinearity and Spectrum Analysis of Drill Strings with Component Mass Unbalance},
	  author    = {F. Abdul Majeed and  H. Karki and  Y. Abdel Magid and  M. Karkoub},
	  country	= {},
	  institution	= {},
	  abstract     = {This paper analyses the non linear properties
exhibited by a drill string system under various un balanced mass
conditions. The drill string is affected by continuous friction in the
form of drill bit and well bore hole interactions. This paper proves
the origin of limit cycling and increase of non linearity with increase
in speed of the drilling in the presence of friction. The spectrum of
the frequency response is also studied to detect the presence of
vibration abnormalities arising during the drilling process.},
	    journal   = {International Journal of Mechanical and Mechatronics Engineering},
	  volume    = {5},
	  number    = {1},
	  year      = {2011},
	  pages     = {58 - 61},
	  ee        = {https://publications.waset.org/pdf/8888},
	  url   	= {https://publications.waset.org/vol/49},
	  bibsource = {https://publications.waset.org/},
	  issn  	= {eISSN: 1307-6892},
	  publisher = {World Academy of Science, Engineering and Technology},
	  index 	= {Open Science Index 49, 2011},