In a reciprocating pump, the crosshead makes a reciprocating straight-line Yunyunji in its slideway. The connecting rod for rocking motion and the plunger for reciprocating motion are connected in a chain form by the crosshead and transmit the force. It is required that under the condition of satisfying the strength, the weight should be as light as possible, the structure should be simple and the plunger and the small end of the connecting rod should be firmly connected, easy to disassemble and maintain. The cross head CAD model of the plunger reciprocating pump has such functions as size calculation, strength check and parametric drawing of the crosshead, which can rationalize and standardize the crosshead design and improve the product design and development capabilities of the company. 1 Crosshead design principle 11 Structure of the crosshead A crosshead pin is used to connect the small end of the connecting rod and the crosshead. The small end of the connecting rod is located in the body of the crosshead and uses a pin to connect the closed crosshead. The crosshead and plunger are connected by cylindrical threads. This kind of structure is simple, light weight, commonly used for small and medium-sized pumps. See cross section. 1.2 Determination of the size of the shoe The diameter of the shoe (1.3) The main dimensions of the crosshead (3) The determination of the diameter of the crosshead The crosshead diameter ds can be preliminarily determined according to an empirical formula, and then corrected after strength verification. 1.4 Crosshead strength Check (1) Cross-head shoe ratio check G: Cross-head weight G and the weight of connecting rods divided by the crosshead; k - Coefficient converted into reciprocating mass; Ratio of crosshead pin to hole seat Press A! ―The length of support of the crosshead pin in the one side pin hole seat; ―The allowable specific pressure value. 2 crosshead design module programming crosshead design is mainly to determine the size of the crosshead, and then cross head shoe relative pressure Ph and crosshead pin and hole seat with pressure P, check. Determining the coefficient coefficient check + Satisfying the crosshead program design flow chart (2) Crosshead design module form interface design Crosshead program design form interface As shown, it is calculated by the calculation coefficient, size calculation and strength The nuclear 3 frame Frame and some command buttons are composed. The calculation coefficient frame is calculated from the allowable crosshead material, the material allowable specific pressure of two drop-down list boxes and the shoe diameter Dh calculation coefficient ki, the shoe length Lh calculation coefficient k2, the pin hole seat B-B cross-sectional area Ab calculation coefficient k33 Composition of text boxes. The sizing framework consists of 12 label boxes that reflect the full size features of the crosshead. The strength check frame determines the main dimensions and strength of the crosshead by comparing the crosshead shoe with the pressure Ph and the crosshead pin and hole seat with the pressure A compared with the two check boxes and the two crosshead design module programs. The calculation formula in the checklist is written as a program. Pay attention to the data transfer of the calculation results of the overall design of the reciprocating pump, plunger, crankshaft, connecting rod and other modules. 3 Cross-head design module parametric drawing sub-module design After the cross-head design module completes dimension calculation and strength check and meets the design requirements, it can cross-head project drawings. This functional principle is to perform 3D drawing software SolidWorks. In the second development, the crosshead feature size calculated by the crosshead design module was automatically plotted on the SolidWorks platform of the three-dimensional drawing software, achieving a high degree of automation. SolidWorks is a feature-based parametric 3D plotting software that can change the solid model through dimensioning. Before using VB6.0 to automatically draw the 3D solid map of the crosshead in SolidWorks, first draw the 3D solid model of the crosshead in the SolidWorks part drawing template, and then save the crosshead solid model to the folder. When establishing a crosshead feature model, it is necessary to analyze the characteristics of the crosshead and perform feature planning so that the correct three-dimensional map can be created using the feature parameters. Parametric Drawing Sub-module Programming SolidWorks uses parametric and feature modeling techniques to provide designers with a good design environment. The API of SolidWorks (Ap-plication Programming Interface) is an application programming interface based on OLE Automation. It contains hundreds of function functions and can be directly called by VB6.0, so it is convenient for secondary development of SolidWorks. SolidWorks organizes its internal data in the form of objects and forms a hierarchy. The topmost object is Sld-Works.Application which is the parent object of other objects. Use the VB6.0 function CreateObect to obtain the object association and manipulate the graphic database by calling the methods and properties of the Application object. In the Click event of the object (command button drawing) of the cross-head drawing form module, add code to transfer the value of the universal cross-head drawing sub-process in the standard module in the reciprocating pump design project. Computer simulation of the average load of spiral cylinders Wang Hongying, Gao Xiaolin (Jixi University, Jixi 158105, Heilongjiang, China) The average load of the rotating drums was simulated by computer, and the simulated curve reflected the change of the drum load with different parameters, thus laying the foundation for the design of spiral drums. Introduction The spiral drum is one of the important components of the shearer. The above is a general-purpose cross-head subroutine in the standard module that has been reduced. After the 3D solids of the crosshead are automatically drawn in SolidWorks, you can enter the SolidWorks drawing environment. You can generate cross-sectional views of the crossheads through the named views and the resulting crosshead views. . 4 Conclusion Reciprocating pump crosshead connected with the plunger, connecting rod, by the main structural parameters of the reciprocating pump and plunger, crankshaft, connecting rod and other key components of the impact of the parameters involved in the calculation of many variables, it is difficult to manually calculate Crosshead design module interface is simple, friendly, intuitive, accurate and reasonable calculation, can be used as a design tool for companies to develop new products, the effect is obvious in use. Foldable Electric Scooter,Folding Scooter,Folding Electric Scooter,Foldable Scooter Ningbo Hiley Technology Co.,Ltd , https://www.hiley-mobility.com
Development of crosshead CAD module for plunger reciprocating pump
Development of crosshead CAD module for plunger reciprocating pump
Core Tips: In a reciprocating pump, the crosshead makes a reciprocating straight-line Yun Yunjiu in its slide. The connecting rod for rocking motion and the plunger for reciprocating motion are connected in a chain form by the crosshead and transmit the force. Requires a lighter weight, a simple structure and a plunger