Roller Profiling for Generating the Screw of a Pump with Progressive Cavities

Abstract

Progressive cavity pumps are used in industry for the circulation of high viscosity fluids, such as crude oil and petroleum products, sewage sludge, oils, salt water, and wastewater. Also known as single screw pumps, these pumps are composed of a single rotor which has the shape of a rounded screw, which moves inside a rubber stator. The stator has an double helical internal surface which, together with the helical surface of the rotor, creates a cavity that moves along the rotor. The movement effect of the cavity inside the stator is the movement of the fluid with a constant flow and high pressure. In this paper, an algorithm for profiling the rollers for generating the helical surface of the pump rotor with progressive cavities is proposed. These rollers are constituted as tools for the plastic deformation of the blank (in case the pump rotor is obtained by volumetric deformation) or for its superficial hardening.

Profiling of the Hob Mill Tool for Generating a Profile Known in Discrete Form

“…The second solution to determine the surface is the one in which it will be modeled by means of polyhedral in which their vertices will be determined by the points belonging to the ordered point clouds. The surface modeling represent, in this case, an approximation that will allow the determination of a normal, located at a point on the surface, this being a significant advantage, since various methods of profiling tools that generate by enveloping can be used, such as Willis's theorem, Gohman's theorem, minimum distance method, Olivier's method, method of planar generating trajectories and so on [1], [7][8][9][10][11][12]. In this paper, a tool profiling algorithm is proposed, which is based on the capacity to measure and represent some surfaces in a methodical cloud of points form.…”

Reverse Engineering Used to Profile a Gerotor Pump Rotor

“…By means of such a technique, Zhang et al [39] established the parametric equation of the theoretical contour curve by analyzing the radius of curvature of the cycloidal gearing using NX10.0 software. Reverse engineering problems have been developed in graphical design environments [40][41][42], with applications, especially in the field of virtual modeling of generating tools of pumps and compressors rotor channels or of different working components whose profiles comprise different shapes, such as circular arcs, straight segments, helical curves, involute-cycloids, cycloidal curves, or various nonanalytical curves [43,44], in which profiling solutions were proposed using a set of software products, such as MATLAB for calculation and CATIA for virtual representation.…”

Use of Reverse Engineering Techniques for Inspecting Screws Surfaces of a Helical Hydraulic Pump

“…Reverse engineering is the process of analyzing a realworld object or environment in order to collect data on its shape, structure and appearance, so that it can be used later to construct digital 3D models (Akerdad et al, 2021). The worm-type pieces existing in the structure of helical pumps and compressors, are working bodies whose profiles include different shapes, such as circle arcs, straight segments, helical curves, involutescycloids, cycloidal curves or various non-analytical curves (Baroiu, Popa et al, 2017, Teodor et al, 2018, Yan et al, 2017, Baroiu, Berbinschi et al, 2017. Studying the energy efficiency problems of these pumps and compressors involves establishing mathematical models of their profiles, comparing various geometric parameters or using graphical methods that can sometimes be considered difficult or time consuming methods (Dong et al, 2019, Joshi et al, 2020, Malov, 2020.…”

“…Studying the energy efficiency problems of these pumps and compressors involves establishing mathematical models of their profiles, comparing various geometric parameters or using graphical methods that can sometimes be considered difficult or time consuming methods (Dong et al, 2019, Joshi et al, 2020, Malov, 2020. The problem that often exists in the processes of reconditioning the screws of the helical pumps and compressors consists in making the tools that generate the helical channels of the worms, starting from the existing physical characteristics, for which, often, there is no specific technical documentation (Baroiu, Popa et al 2017). In such situations, obtaining the constructive shape of the screws can be done by effectively measuring them, making 3D models of the screws and, starting from them, profiling the generating tools (disc tools or cylindrical-front tools), with which the helical channels of the pieces will be processed (Baroiu, Popa et al, 2017).…”

“…The problem that often exists in the processes of reconditioning the screws of the helical pumps and compressors consists in making the tools that generate the helical channels of the worms, starting from the existing physical characteristics, for which, often, there is no specific technical documentation (Baroiu, Popa et al 2017). In such situations, obtaining the constructive shape of the screws can be done by effectively measuring them, making 3D models of the screws and, starting from them, profiling the generating tools (disc tools or cylindrical-front tools), with which the helical channels of the pieces will be processed (Baroiu, Popa et al, 2017). In this paper, it is proposed to redesign two pieces of a helical pump (driver and driven screws) based on numerical models obtained by scanning.…”