ИССЛЕДОВАНИЕ ЭФФЕКТИВНОСТИ ПОРШНЕВОГО КОМПЕНСАТОРА УЭЦН С КВАЗИНУЛЕВОЙ ЖЕСТКОСТЬЮ Часть I. МЕХАНИЗМ ВИБРОИЗОЛЯЦИИ УЭЦН С ПНЕВМОПРУЖИННЫМ КОМПЕНСАТОРОМ

Abstract

For the purpose of compensation of pressure differences in the pipes on release from the electrocentrifugal pump (ESP) authors suggest to use pneumatic compensators (РС). In article it is shown that the frequency of pressure differences on ESP is low, therefore, for effective vibration insulation of the РС piston its own frequency of oscillation should be small. For the existing РС it is impossible. Effective vibration insulation of the РС piston is possible in case of the force characteristic of the РС having the working site with quasi-zero stiffness. Set of systems with positive and negative stiffness is necessary for obtaining quasi-zero stiffness. Structurally, РС with quasi-zero stiffness invited to perform as a set of pneumospring and a package of disc springs in series, which is located inside the pneumospring and props up its piston. The pneumospring represents system with positive stiffness. The package of consistently connected dish-shaped springs represents system with negative stiffness. Parameters of dish-shaped springs are picked up so that the force characteristic of all package of springs had the site of negative stiffness. As a result of addition of negative stiffness of a package of dish-shaped springs and positive stiffness of a pneumospring the resultant system gains quasi-zero stiffness. Calculations of displacement of the РС piston at sudden emergence of pressure difference on ESP in case of quasi-zero stiffness and in case of elastic preload of the piston, that is really for the existing modern РС, are presented in the article. At elastic preload of the piston his displacement is tens times less, than at in case of quasi-zero stiffness. In case of quasi-zero stiffness of the РС displacement of its piston happens practically in any difference of pressure that leads to increase in overall performance of all ESP.