Research On Type Synthesis And Key Technologies Of 90/180 Degree Upender For Nuclear Power Large Rotating Workpieces

Nuclear power large rotating forgings include straight shells,tapered shells,tubesheets and heads,etc,which is an important component that constitutes nuclear island equipment such as Reactor Vessel,Steam Generator and Pressurizer.In the process of manufacturing,assembly and flaw detection of nuclear power large rotary forgings,90 or180 degree flip is often required.However,research on the type synthesis of the upender for large nuclear forgings is rarely reported,while other large workpiece upender have problems of single function and poor ability to adapt to different workpiece types,sizes and specifications.Type synthesis theoretical study of a 90/180-degree upender for large nuclear forgings is carried out for this problem,and a series of novel 90/180 degree upender are obtained.The space vector is used to describe the location of the rotating workpiece,that is,the vector starting point represents the workpiece position,and the vector direction represents the workpiece orientation.Based on the transformation effect of the rotation matrix on the space vector,60 kinds of rotation matrix permutation for achieving 180 degree flip of the rotating workpiece with 90 degree steps are obtained.The three principles of eliminating the redundant permutation and merging the same kind of permutation are proposed,and the I,II and III types of flipping motion models are obtained.By deducing the Lie algebra of the homogeneous transformation matrix of the rigid body motion in each step of the flipping motion model,and expressing it as twist,the corresponding kinematic pair is obtained.The principle of kinematic pair sequence transformation is proposed,and the initial basic machines of 19 types of 90/180 degree upender in 3 series is obtained.For the three initial basic machines,by adding the prismatic joint ^zP,15 kinds of 90/180 degree upender overall machines were obtained.Aiming at the limitations of the application of type I machines and type Ⅲ machines,the type synthesis of multi-mode 90/180 degree upender that is to realize flipping motion of class Ⅰ and class III flipping motion models is studied.By combining the ^xR₁^xR₂mechanism and the ^xR₁+^xR₂ mechanism in type Ⅰ initial basic machines with the ^xR^y_1（4）R_2（3）mechanism in type Ⅲ initial basic machines,6 initial basic machines of multi-mode90/180 degree upender are obtained.For each of these initial basic machines,the overall machines of 79 multi-mode 90/180 degree upender are obtained by adding the prismatic joint ^zP.Finally,the kinematics analysis of the“Nuclear Large Forgings 90/180 Degree Heavy Duty Upender”based on the ^xR₁^zP₁^xR₂ mechanism was carried out,the mechanism’s Jacobian matrix and the velocity coordination function of the traction flipping table of the positive and negative hoisting systems is obtained.Aiming at the control problem of the rope traction mechanism,the antagonistic drive control strategy of master-slave cooperative motion is proposed,and the optimization objective function of the antagonistic force is established.Combined with the dynamic analysis of the heavy duty upender,the relationship of antagonistic force and external load and joint variables are obtained.