Abstract: Currently in China, the computing system of the straightening force of the six-rollers straightening machine generally follows
the traditional computing system. The force status of the traditional computing system for the straightening force deviates far away from
the actual force status of the roller system in the six-rollers straightening machine. In the traditional system, the computing model of the
straightening force of the six-roller straightening machine was based on the roller shape of hyperbola, which led to the length of the
contacting line between the tube and the straightening roller to be excessively short, i.e., only 0.1–0.2 of the length of the roller. Thus
the constructed computing system has relatively large difference from the actual measured result. To solve the above problems,
flattening straightening and bend straightening are analyzed on the basis of materials mechanics and bend beam theory, the roller shape
using the envelope method of  А.И.Целиков is generated, and a new computing system for straightening force in six-rollers
straightening machine is built. The roller  shape of the straightening roller, on which the new computing system for the straightening
force is based, is designed according to  the envelope method under the condition of ideally full contacting between the tube and the
roller body of the straightening roller, therefore the new computing model accords with the practical status of straightening force.
According to the comparison of the new computing system with finite element method and the actual measured result of straightening
force, it has been proved that the computation accuracy of the new computing system  for straightening force satisfies the practical
requirements of engineering. New six-rollers straightening machines are designed and manufactured according to the new calculation
system, and the new machines not only have higher precision and quality, but also have adopted the force sensor and computer and
combined with the new computing system for straightening force to realize the fully automatic adjustment of the straightening machine.
The new six rollers straightening machine have obtained notable economical and social benefits.8010
 Key words: straightening, roller shape curve, flattening, bend, finite element analysis
  1  Introduction
Tube straightening machine is the finishing device for
straightening steel tubes. When straightening, the
straightening force has a great influence on the quality and
precision of the straightening steel tubes. Since the quality
of straightening device currently at home is quite different,
some theoretical problems are obscure, and the traditional
model for calculating straightening force is too
conservative, it results in that products of high quality are
not able to be manufactured, especially in that straightening
waste products are often produced and thus normal
production are directly affected for some old or small
factories.
In the old straightening machine, many roller-shaped
curves are hyperbola, which is proved to be flawed in
practice and theory. Hyperbola is applicable for small
straightening range, but its contact line is very short and
contact stress is high, therefore, when the inclination angle
for the straightening roller is big, two short contact lines are                                                                   
formed when the tube being straightened contacts with the
straightening roller, which leaves two obvious impress on 矫直力的计算体系创新英文文献和翻译:http://www.youerw.com/fanyi/lunwen_6191.html