SU1611595A1 - Method of cooling hog-nosed drill - Google Patents

Abstract

The invention relates to a machine tool industry, in particular to methods for cooling a core drill. The aim of the invention is to increase the cooling efficiency, especially when cooling austenitic steels. When machining part 10, the drill with its cutters 5 drills channel 11. At the same time, coolant (coolant) is supplied through tubes 3 placed in the grooves 2 on the outer surface of the drill body 1 to the cutting edges 4 of the cutters 5. At the same time, pressurized air is supplied tubes 7 in the cavity 8 of the casing 1 and thence through the gap 13 under the pressure P _in = ^K. T is supplied to the cutting edges 4. The air cools the cutting edges 4 by blowing off the coolant film and removing the chips from the cutting area. K = 0.133

T - depth of drilling, see 1 s. f-ly, 2 ill.

Description

1

The invention tends towards machine tool construction, in particular to methods for cooling an Allen drill.

The purpose of the invention is to improve cooling performance, especially when cooling austenitic steels.

FIG. 1 shows a scheme for implementing the method; in fig. 2 is a view A of FIG. 1. For carrying out the method, a top is used which contains a glass-like body 1 with grooves 2 on its outer surface to position the tubes 3 of the coolant supply system (LCL) to the cutting edges 4 of the cutters 5 and fixed to the bottom 6 of the body 1 of the tube 7 housing cavity 8 1. In addition, guide plates 9 are fixed on the drill bit.

The method is carried out as follows.

Fix the stationary ring drill and rotate part 10. When the drill is fed into the parts, the channel I is drilled to form (drill) the rod 12. During the cutting, coolant 3 is fed to the cutting edges 4 of the cutters 5, cooled by wrapping them with a coolant film. Simultaneously air is fed through the tubes 7 into the cavity 8 and from it through the annular gap 13 between the rod 12 and the inner surface of the housing 1 to the cutting edges 4. The air blows off the coolant film, additionally cooling the edge 4, and additionally cools the cutting zone by reducing it temperature during expansion of the air stream leaving the cavity 8. The air leaving the cutting zone picks up the chips and removes them along with the coolant. In order to ensure a stable air supply during deep drilling, the air pressure Рв is chosen according to the formula

Rv K t,

where K 133 when processing steels of austenitic class;

t is the drilling depth, see Example. A 0360 mm annular drill is secured in the tool holder 1A660, and the workpiece 10 (part

195-5 820 mm, length 1280 mm from steel 08Х 8Н10Т for the main circulating pump of the nuclear power plant) impart rotational motion. Set the cutting mode:

at 20 rpm the feed of the drill is 0.15 mm / rev. During operation, coolant under pressure through the tubes 3 is fed into the cutting zone individually for each of the cutters 5. Compressed air is fed into the internal cavity 8 of the housing I through the inner tubes 7,

which passes through the annular cavity 13 between the drilled rod 12 and the inner surface of the housing 1 to the drilling zone. Compressed air picks up broken chips and, together with coolant, throws out of the drilled ring hole 11. At the same time, the vibration of the machine and the ring drill disappears, clogging of the drill is eliminated (broken chips and outward), the hole processing cleanliness and the drill rod (spool from the twisted chip) increases. , the life of the core drill increases.

Upon reaching a drilling depth of 100, 200, 400 and 600 mm, respectively, the pressure of the supplied air is 1.33; 2.66; 5.32 and 7.98 kgf / cm1

Claims (2)

Invention Formula . The method of cooling a circular drill, according to which the drill channels SHUTCH coolant (coolant) on its cutting edges and serves air under pressure with its subsequent spraying, characterized in that, in order to increase the cooling efficiency, air is supplied through the gap between the inner wall of the drill body and the surface of the drilled rod, and the air pressure Рв is chosen according to the formula . t, where K - coefficient, kg / cm; {depth of drilling, see 2. A method according to claim I, characterized in that, in order to increase the cooling efficiency of austenitic steels, the coefficient K is chosen equal to 0.133.