SU1535706A1 - Method of grinding with periodic dressing of wheel - Google Patents

Abstract

The invention relates to machining and can be used for grinding with periodic grinding wheel. The aim of the invention is to improve processing performance. To do this, periodically correct the wheel when grinding with a rotating right-hand roller, while the relative circumferential speed at the point of contact of the right-hand roller and the grinding wheel is chosen opposite to the direction of the circumferential speed of the wheel in the course of grinding. Various combinations of directions of rotation of a circle and a roller are provided during dressing and processing, ensuring the above condition. 3 hp f-ly., 6 ill., 2 tab.

Description

The invention relates to abrasive machining.

The aim of the invention is to improve processing performance.

In the process of grinding over time, a certain profile of cutting abrasive grains of a circle is formed, characterized by the formation of wear areas and intake cone with the formation of negative cutting angles or their increase. When the circle is blunt and it is salted, it becomes necessary to restore the cutting properties of the grinding wheel using various methods of dressing. Depending on the direction of the forces acting on the abrasive grains during the dressing process, a profile of cutting grains may be formed that is close to the profile of the grains formed during the grinding process, or opposite to it (with different directions of forces acting on the grain during the editing and grinding process). In order to increase the cutting ability of the wheel and increase its durability, it is necessary to ensure the formation of the cutting relief of the grains of the circle opposite in the direction of the relief of the grains of the circle when grinding. In this case, the circle for a certain time until blunting works with more favorable cutting angles for each of the abrasive grains. The formation of this microrelief is provided by the opposite direction of the cutting forces acting on the circle in the cutting process and in the grinding process. The opposite of the direction of the cutting forces is uniquely determined by the opposite of the relative circumferential speeds.

with

SL

sl

about

OE

at the points of contact of the grinding wheel with the right tool and with the workpiece. Since the circumferential speed of the circle when grinding is always greater than the peripheral speed of the part, the direction of the relative circumferential speed when grinding is determined by the direction of the circumferential speed of the circle. Thus, the formation of the opposite in direction of the profile of the cutting abrasive grains during grinding with periodically correcting the circle with right tools is provided by selecting the direction and value of the peripheral speeds of the circle and the right tool from the condition of providing the opposite direction of the relative peripheral speed at the contact point of the right tool and the circle with the peripheral speed of the wheel in the grinding process.

FIG. Figure 1 shows an approximate profile of cutting abrasive grains in a circle before dressing or processing, where & - cutting angle -, in FIG. 2 - profile of the abrasive wheel, formed in the process of dressing (V0 - relative circumferential speed at the point of contact of the circle with the right tool) or machining the part (VK - circumferential speed of the circle in the process) 1, fig. 3 shows the profile of the abrasive grain after straightening the wheel and the direction of the relative circumferential speed in the process of straightening V0 and the circumferential speed of the circle during the subsequent processing of Vk; FIG. 4-6 - schemes for implementing the method. i

According to FIG. 4, when straightening, the grinding wheel 1 and the right roller 2 rotate in the opposite direction, the absolute value of the peripheral speed of the roller (V.) exceeds the absolute value of the circumferential speed of the wheel (VK), and the direction of rotation of the grinding wheel during straightening and grinding the part 3 choose the same; according to FIG. 5 when straightening, the right-hand roller 2 and the grinding wheel 1 are rotated in one direction, and the directions of rotation of the grinding wheel are mutually opposite during straightening and grinding; according to FIG. 6, when straightening, the grinding wheel 1 and the right roller 2 rotate in the opposite direction, and the absolute value of the peripheral speed of the roller is chosen less than the absolute value of the peripheral speed of the wheel, while the grinding wheel is rotated in the opposite direction during dressing and grinding. For all cases, the relative circumferential speeds V0 and the cutting forces P acting on the circle are directed in opposite directions when editing and grinding. The grinding scheme is given for external round grinding.

The diamond wheel 1A1 250 20x76x6 AC6 1Z5 / 100M-M1-04-100 processed the product from X12M steel on a surface grinder with periodic grinding of a circle with an abrasive wheel III 100 16x32 24 A25 HCM 7K5.

According to a known method, the direction of rotation of the roller and the circle coincides without a subsequent change in the direction of rotation of the circle during grinding, with V to 30 m / s, Vp 20 m / s.

The proposed method used three options.

Example 1. The circumferential speed of the right-hand tool is 20 m / s, the circumferential speed of the grinding wheel during dressing is 10 m / s. The direction of rotation of the grinding wheel is opposite to the direction of rotation of the right wheel. The direction of rotation of the circle when grinding and editing unchanged. The speed of the grinding wheel was controlled using the EKT-2D-25/3804 HPU electric drive. In the grinding mode, the longitudinal feed was 10 m / min. The transverse feed was 5 mm per stroke, the cutting depth was 0.01 mm; VK 30 m / s; in the straightening mode, a cross-feed of 1 m / min is 0.02 mm;

Example 2, The circumferential speeds of the right tool and the grinding wheel during dressing, respectively, 20 and 10 m / s. The directions of rotation of the grinding wheel and the right roller coincide. The rotation of the circle during grinding and editing is directed in opposite directions.

Example 3. The circumferential speed of the right tool and the grinding wheel during dressing, respectively, 20 and 25 m / s. The direction of rotation of the grinding wheel and the right roller is opposite. The rotation of the circle when editing is directed in the opposite direction to the rotation during grinding. g

D1-5

Grinding indicators are shown in the table.

 The cutting ability of the wheel was determined indirectly by the change in the effective grinding power. The limitation of the operating time of the grinding wheel (durability of the wheel) was the excess of the waviness of the permissible value of 2.5 µm (at the profile length AO mm). The amplitude of the vibrations was determined with respect to the idle amplitude.

As can be seen from the table, the proposed method of abrasive machining with periodic circle dressing provides an increase in the cutting ability of the wheel, as evidenced by a decrease in the effective grinding power compared to the known method by 33-50%, and allows an increase in the wheel flow by 25-200%.

Claims (4)

1. A grinding method with periodical wheel alignment, in which the part and the grinding wheel rotate and periodically correct it with a rotating right-hand roller, characterized in that, in order to increase processing performance, the relative circumferential speed at the point of contact of the right 7066 The roller and the grinding wheel are chosen opposite to the direction of the circumferential speed of the wheel in the grinding process. 2. The method according to claim 1, characterized in that the direction of rotation of the circle when editing is chosen coinciding with the direction of rotation grinding wheel during processing, and the direction of rotation of the roller is chosen opposite, while the absolute value of the peripheral speed of the roller is chosen large absolute 5 values of the peripheral speed of the circle when editing. 3. A method according to claim 1, characterized in that the direction of rotation of the grinding wheel with 0, the dressing and the roller are chosen opposite to the direction of rotation of the grinding wheel during processing. 4. The method according to claim 1, characterized in that the direction of rotation is polished. when straightening the wheel is chosen opposite, and the direction of rotation of the right-hand roller coincides with the direction of rotation of the grinding wheel during processing, while the absolute value of the peripheral speed of the roller is chosen less than the absolute value of the peripheral speed of the wheel when straightening. 0.3 0.18 0.2 0.15 1.25 1.11 1.15 1.06 V0 V "+ Vp tt Pz P Gn-MU FIG. b Compiled by V.Onegin Editor I.Rybchenko Tehred M.Lidyk Order 75 Circulation 587 VNII11I of the State Committee for Inventions (opened at the USSR Scientific and Technical Committee 113035, Moscow, Zh-35, Raushsk nab., A / 5 FIG. five Pz Proofreader M.Maksimishinets Subscription