OIL-WELL PUMPING UNIT Russian patent published in 1998 - IPC

FIELD: oil industry; production of oil at any well. SUBSTANCE: pumping unit includes two drums. Generatrices of drum may be concave in formal generatrix of one drum may be convex in form and that of other drum may be concave in form. Two halves of band stack form flexible tractive member connected with pump plunger. Bands of flexible tractive member have cross section in form of ring member with height not exceeding B/π,, where B is band width. Axis of upper drum is shifted horizontally relative to axis of lower drum in direction towards axis of oil well by distance no less than B/π.. When drive is switched on, drums may revolve in opposite directions. EFFECT: enhanced reliability. 5 dwg