SU781312A1 - Blade-type expanding tool - Google Patents

Description

The invention relates to drilling equipment, and more particularly to a rock cutting tool of a sliding type, used to increase the diameter of a well and when drilling without lifting drill pipes.

A plug-in blade extender is known, including sliding blades connected to the housing by a link of the rocker type (hinge movable in the axial direction) and extended to the working position by a central rod connected to the hydraulic mechanism [1].

The disadvantage of this expander is the small area of the rock-eroding surfaces, which is caused by the location of the hinge axes above the working elements of the blades.

Also known is a plug-in extender, 20 including a housing, a piston with a rod with blades pivotally mounted on it, interacting with the outer conical surface of the housing and the rod. In this expander, the axis of the ball-25 peers is located below the working elements of the blades, which can significantly increase the working and calibrating surfaces of the blades and thereby increase the resource of their work (2)

The drawback of the expander is that during operation, as wear occurs on the surfaces that fix the working position of the blades, gaps arise that cause a further progressive increase in the wear of these surfaces, which leads to a deterioration in drilling performance and a decrease in the service life of the expander.

The purpose of the invention is to increase the service life of the expander due to the elimination during the operation of the backlash between the housing and the blades that occur as the wear.

This goal is achieved by the fact that the lower sections of the stem blades in contact with each other are made inclined, and the stem is made with a longitudinal slot to accommodate the axes of the blades, while the blades are equipped with spring-loaded pushers for fixing them in the working position.

Figure 1 shows the expander, a longitudinal section; figure 2 is the same, section a — a in figure 1.

• the expander prefers a lean case 1, 'in which through slots 2 it is located. blades 3 with reinforced, for example diamonds, working surfaces -

TNI 4. The blades are fixed on the central stem 5 by hinge axles 6, which are placed in the longitudinal grooves 7, made in the protrusions 8 of the rod 5. In the body of the blades 3 springs 9 are installed, which push the blades 3 through the pusher 10 to the extreme position. To the body 1 are attached Sneed sub 11 carrying a pilot bit (not showing in the drawing but · ^) .In the top of the stem 12. The piston is _L blades have bevels 13 and ledges formed in the housing 14. At the stem and the housing are conical surfaces 15 and 16. _#

The expander works as follows. fifteen

When the expander is in working position, the stem 5 is moved upward by a hydraulic piston mechanism 12, raising the blades 3, which, sliding with their faces 13 along the ledges 14 jq of the housing 1, turn outward and wedge along the conical surfaces 15 on the stem and 16 on the housing.

As wear during the drilling of the supporting conical surfaces 15 and __ 16 under the influence of the hydraulic force of the ** piston mechanism moves upward, due to which the formed gaps are eliminated.

Thus, in the device of the expander the gap-free, rigid fastening of the blades in the working position is constantly supported, which should provide a significant increase in the durability of the blades and associated parts. The rigidity of the fastening of the Dolzhya blades also contribute to an increase in the mechanical speed of penetration. ,.

Claims (2)

RL 4. The blades are fixed on the centric stem 5 of the hinged axles b, which are placed in the longitudinal grooves 7, made in the projections 8 of the rod 5. In the body of the blades 3 springs 9 are installed, which through the pusher 10 squeeze the blades 3 to the extreme position . A sub 11 is attached to the housing 1; a pilot bit is attached (not shown in the drawing), a piston 12 is located in the upper part of the stem. The blades have bevels 13, and ledges 14 are made in the housing. On the rod and the housing there are conical surfaces 15 and 16. Extender with Leducci image. When the expander is moved to its working position, the rod 5 by the hydraulic piston mechanism 12 moves upwards, raising the blades 3, which slide along edges 13 of the housing 1, turn outwards and wedge along the surfaces 15 on the rod and 16 on the housing. As the cone surfaces 15 and 16 are depleted during drilling, the hydraulic force of the piston mechanism moves upward under the action of the hydraulic force, so that the gaps that are formed are eliminated. Thus, in the expander device, the backlash-free, rigid fastening of the bogies in the working position is constantly maintained, which should ensure a significant increase in the durability of the blades and the attached blades. The stiffness of fastening the blades should also contribute to an increase in the mechanical penetration rate. Formula of the Invention Blade Expander, comprising a housing, a piston with a rod with hingedly fixed blades on it, interacting with the outer conical surface of the housing and a rod, which is designed to increase the pecypda of the expander, the lower portions of the stem blades, in contact with each other, are inclined, and the rod is made, with a longitudinal slot for accommodating the axes of the blades, while the blades are provided with spring-loaded push rods for fixing them in the working position. Sources of information taken into account in the examination 1. The author's certificate of the USSR 481689, cl. E 21 B 9/26, 1972. 2. Avt Orsk certificate of the USSR 583278; cl. E 21 V 9/26, 1974 (prototype).