SU1724413A1 - Shock absorber of plunger of hydraulic coupling assembly of vertical no-anvil hammer - Google Patents

Abstract

FIELD OF THE INVENTION The invention relates to mechanical engineering, in particular, to careless hammers. The purpose of the invention is to increase reliability. The plunger absorber of the hydraulic unit of the vertical non-hammering hammer contains a package (P) of corrugated sheets with the same corrugation pitch. The supporting elements (OE) are made in the form of C-shaped brackets. On the side of the upper and lower depressions, two rows of vertical holes are made in depth, 1.15-1.2 times the length of the bent ends (OK) of the mentioned brackets. OE with these ends are installed in the holes of P. At least in two of the OE located in the upper and lower depressions of P, one of the OKs is made Long, exceeding half the height of P. 2 z.p. f-ly. 5 il. Yo

Description

The invention relates to mechanical engineering and can be used in the construction of forging and stamping equipment.

The hammerless hammer with hydraulic connection of women is known.

The disadvantages of the hammer include an increase in the mass of lateral rods due to the introduction of additional plungers into the structure, as well as the retention of lateral and central rods shock absorbers that are difficult to access for repair. The presence of rubber-metal shock absorbers significantly reduces the efficiency of the hammer.

Known careless hammer with an impact energy of 630 kJ. Rubber-metal shock absorbers are used on the forging hammer. Rubber whites are connected with metal gaskets by vulcanization. In terms of sheets are shaped like round washers with internal perforations. The ends of the rubber washers have rounds, directed

inside the material. Material - rubber mixture based on natural rubber.

Inmeta shock absorbers have a working duration of 8-12 weeks, shock absorbers made on the basis of rubber plates have a working duration of up to 1 week. The rubber sheets of these shock absorbers have the shape of round washers with conventional perforations and six holes of 060 mm. Sheets are mounted loosely on metal gaskets and form a shock absorber design similar to that of a hammer-free knot.

A disadvantage of rubber metal shock absorbers is low durability, which leads to losses associated with the replacement of shock absorbers and just the hammer.

Also known is the vibration insulating subsurface gasket of a vertical hammer containing equidutiXI

Yu

WITH

one-over-one another plumbing in the form of packages of corrugated sheets with the same pitch of corrugations, provided with supporting elements with a concave working surface, upper supporting elements with a convex working surface and separating elements.

This technical solution is not applicable as a plunger shock absorber of the hydraulic unit of the safety-free hammer due to its inoperability, which is explained by several reasons. The presence of an elastic bond between the women, which is the shock absorbers, causes the women to oscillate with respect to a common center of mass when moving to a blow, and they approach the shock at different speeds, and the mismatch in speeds is higher, the smaller the shock absorber stiffness . Thus, for a hammerless hammer with an impact energy of 1500 kJ, the difference in speeds of movement of women for a strike not exceeding 0.3 m / s can be obtained if the total stiffness of the side shock absorbers is more than 1.8-108 N / m. After the impact, the upper engine with a rebound speed of 1.5 m / s moves upwards, and the side rods, together with shock absorbers with a impact speed of 3 m / s, continue downward movement and are slowed down due to pressures from the fluid in the hydraulic tank to the front the surface of the plungers interacting with the rod. As a result of the movement of the upper head and side rods in different directions, and between them are installed shock absorbers, the load from the shock absorber is removed and a gap appears between the support surface of the head and the shock absorber, the size of which reaches 30-40 mm. The gap can be reduced or eliminated by reducing the stiffness of the shock absorbers, but this increases the magnitude of the mismatch of the speeds of the women to the impact, which entails other adverse phenomena, such as water hammering the fluid in the hydraulic tank, impact of the lower woman on the stationary shock absorbers, etc. After the side rods stop, they start moving upwards, the gap between the pedestal supporting surface and the shock absorber is selected and side rods are braked, at which pressures related to the area of the shock absorbers in the plan reach 9.0-106 Pa (EOatm). The gasket is designed to operate at pressures up to 1.2-110 Pa (12 atm), increasing the pressure on the gasket leads to loss of stability of the sheets at the tops of the corrugations in contact with the lower and middle separation elements, with a significant decrease in the cyclic strength resource. In addition, there is uncertainty in the position of all the separation and support elements. At the moment of formation of the gap, the shock absorber is completely unloaded, and the presence of vibrations leads to a displacement of the separating and supporting elements relative to the packs, with their likely contact with the frame and possible jamming between the frame and the frame.

The purpose of the invention is to increase the durability of the shock absorber by maintaining its performance and damping properties during operation.

The goal is achieved by the fact that

in order to increase reliability, the supporting elements are made in the form of -shaped brackets, in the package of corrugated sheets on the side of the upper and lower hollows are made

two rows of vertical holes with a depth of 1.15-1.2 times the length of the bent ends of said brackets, with the supporting elements being installed with these ends in the holes of the bag. At least

for two supporting elements located in the upper and lower depressions of the package, one of the bent ends is made longer than half the height of the package. To eliminate possible rotation of the package with

The supporting elements installed in it around the vertical axis of the stem are intermediate plates. Each intermediate plate is made with two opposite edges bent under

the right angle in opposite directions, with the intermediate plates with oppositely directed edges connected to the side surface of the stack, and the oppositely directed edges, respectively, of the upper side - with

the side surface of the women, the bottom - with the side surface of the plunger.

FIG. 1-5 shows a shock absorber; in fig. 2 shows section A-A in FIG. one; in fig. 3 shows a section BB in FIG. one; in fig. 4 - section bb

in fig. one; in fig. 5 is a section of YYD in FIG. 3

The plunger damper of the hydraulic communication unit contains a package of corrugated sheets 1 with openings in which the bent ends of the upper 2 and lower 3 supporting elements are made, which are made in the form of -shaped brackets in contact with the upper 4 and lower 5 intermediate plates. The oppositely directed edges of the intermediate plates are connected with the lateral surface of the package 1, and the oppositely directed edges, respectively, of the upper one - with the lateral surface of the female 6, the lower one - with the lateral surface of the support shoe 7 of the plunger 8 (Fig. 3). Axles

The blind holes are located in the depressions of the corrugations and perpendicular to the supporting surfaces E and F of the shock absorber.

The shock absorber works as follows.

Upper 6 by means of a pneumatic actuator (not shown) begins an accelerated downward motion, acts on the intermediate plate 4, which transmits force to the upper supporting elements 2, which in turn affects the package of corrugated sheets 1. The package, acting on the lower supporting elements 3, transmits the force on the lower intermediate plate 5, the support shoe 7 and the plunger 8. The hammer is symmetrical with respect to the frontal plane passing through its vertical axis and has, respectively, two side plungers (in the drawings one amort is shown) isator and one plunger). The side plungers 8 that received movements from the upper female 6 act on the fluid in the hydraulic tank. The pressure in the latter rises; the central plunger is exerted by the force from the increased pressure of the fluid, which is transmitted to the central rod and through the central shock absorber to the lower woman, which moves against the upper woman (hydraulic tank, central plunger, central shock absorber and lower woman). Reverse idling is carried out similarly with the only difference that the plunger 8 is the leading one. Neither forward nor reverse idling is limiting to the shock absorber. At direct idling, the acceleration of the bab is at the level of 0.5 g (g is the acceleration of the free fall), and the dynamic component of the force acting on the shock absorber does not exceed 50% of the static one.

Maximum loads occur on the shock absorber immediately after impact. At the moment of impact, the lower and upper women, as well as the shock absorber and side plunger, have a speed of 3 m / s. In the process of impact, the lower and upper women brake the vehicle and acquire rebound velocities equal to about 1.5 m / s during a hard impact. The plunger 8 does not participate in the impact of the forging, but at the moment of the impact it continues moving downward at a speed of 3 m / s and moving downward until its kinetic energy is converted into the potential energy of fluid compression in the hydraulic tank. During the movement of the female 6 and the plunger 8 in different directions, the shock absorber is released from the load, and the energy of elastic deformation is spent on increasing the kinetic energy of the plunger and the female and on compressing the fluid in the hydraulic tank. Considering that the decrease in the stiffness of the shock absorbers is limited by the occurrence of mismatch in the speeds of women at direct idling, for real hammers the difference in the movements of the plunger

8 and women 6 appear to be larger than the elastic deformation of the shock absorber at the moment of impact, which leads to the formation of a gap between the bearing surfaces of the woman and the shock absorber.

0 The prevention of the rotation of the shock absorber and the support shoe 7 relative to the plunger axis is achieved by the presence of intermediate plates 4 and 5, each of which is made with two opposite edges;

5 bent at a right angle in opposite directions. The oppositely directed edges of the intermediate plates are connected to the side surface of the package 1, and the oppositely directed edges, respectively

0 top - with the side surface of the female 6, bottom - with the side surface of the support shoe 7 of the plunger (Fig. 3). The ends of the supporting corrugated sheets prevent rotation of the individual corrugated sheets relative to each other.

5 elements that are made in the form of (.- General brackets and are installed in holes made in the package on the side of the upper and lower cavities, and since the length of the bent end of the support element is more than half

0 of the package height, the folded ends of the upper and lower supporting elements overlap each other, which ensures that any two corrugated sheets of the package are prevented from turning relative to each other.

5 After the plunger 8 stops at its lowest position, it begins to move upwards under the action of the pressure from the fluid in the hydraulic tank, the gap between the supporting surface of the female 6 and the supporting surface

0 F of the intermediate plate 4 is selected, the dynamic deformation of the shock absorber begins, during which a part of the kinetic energy of the plunger is converted into the energy of elastic deformation

5 of the shock absorber, and since the plunger reduces the speed to the magnitude of the speed of the female, part of the kinetic energy of the plunger remains unused.

Example. Baseline: Hammer

0 vertical with no impact energy of 1600 kJ; speed of women to the beginning of impact, m / s; the mass of each woman t; speed of rebound of women, 5 m / s; mass of side plungers t; fluid volume

5 in the hydraulic communication system of women, 6 m; the elastic modulus of the fluid (water), 2 10 N / m2, fluid pressure: static MPa; with direct idle MPa; with reverse idle MPa; total equivalent zAAKUj m (Vy2-Vo2) / 2; , 35-104J;

106H;

lateral shock absorber strength, 8 -10 N / m. Dimensions of a single shock absorber 1.0 mx 0.6 m хО, 46 m.

According to the law of conservation of energy, the work of the elastic deformation of shock absorbers after impact is equal to

A Aksh + Aua + AUZH (1)

where Aksh is the change in the kinetic energy of the side plungers during the time between the start of the impact (plunger speed 3 m / s) and at the end of the deformation of the shock absorbers (the plunger speed is equal to the rebound speed of the female -1.5 m / s);

2- V,

J; (2)

АУа - potential energy of lateral shock absorbers during their unloading at the moment of impact

(1- p} / 2C, (3)

here P is the force acting on the shock absorbers at the direct, idle course of the falling parts,

, 5dM,, 5

(p - energy absorption coefficient, shock absorbers per cycle load - unload, yo, 34;

, 2 103J;

AUJ - the change in the energy of the elastic deformation of the liquid, spent on the change in the kinetic energy of the side plungers and then transformed into the elastic deformation of the shock absorbers;

Auj (Pn2-Po2) Al / (2E) 2.2 104J (4)

After substituting into (1) the numerical values of the components, (2) - (4), we obtain the value of the energy imparted by the shock absorbers after the impact;

, 67

The maximum force developed by the plungers during braking during the elastic deformation of the shock absorbers is

Pa V 2 A, 15 107N (5)

Based on the data obtained, a laboratory sample of the shock absorber was made and its stiffness was determined under the condition that the corresponding forces exerted; The area of the shock absorber in plan is 0.05 m, which is 1/24 of the total area in terms of two side shock absorbers.

The laboratory shock absorber includes a package of 185 corrugated sheets 2 mm thick, with corrugation parameters: a pitch of 60 mm, height (span) of the corrugation is 16 mm, the inner radius at the top of the corrugation is 15 mm, the material is 65G steel, the package dimensions in plan 0 , 15x0.33 m, the forming corrugation is located along the short side of the package,

104J.

-

five

10 15

20

50

55

25

thirty

35

40

45

supporting elements in the form of smooth cylinders with a diameter of 30 mm. The force applied to the 0.05 m2 area of the work package is

Re Ra / 24 4.8 GO5 N.

Experimental studies were carried out with a maximum force of 5.0 Iu (50 tons s), the rigidity of the laboratory shock absorber was 7.03 107 N / m. Taking into account the 1/24 ratio of laboratory and working shock absorbers, the rigidity of the two side shock absorbers is

, 68 109N / m,

With such stiffness, the maximum force on the side shock absorbers is equal to Ra

- / 2: 7 G 111-10Ph.

The main parameters of the plunger shock absorber of the hydraulic communication unit of a vertical loose hammer with an impact energy of 1600 kJ: dimensions 1.0x0.6x0.4 m; the number of corrugated sheets in the package 185; corrugation parameters; pitch 60 mm, span of 16 mm, the radius of the inner surface at the top of the corrugation 15 mm; characteristics of the blank for the production of corrugated sheets: material - steel 65G, sheet thickness 2 mm, dimensions 1.0x0.67 m; the diameter of the support element is 30 mm, the material is steel 40HN; equivalent stiffness 8.4 10 N / m; nominal force 5.5 106 N (550 t s).

The length of one (larger) of the two bent ends of the supporting elements does not accidentally have a one-sided restriction, since it is the minimum length, which must be more than half the height of the package in the unloaded condition, ensures the achievement of the goal. The length of one of the two bent ends, at least in two supporting elements located on both sides of the package, if it is more than half its height, ensures the stable position of the individual corrugated sheets in the package, preventing them from turning relative to each other during the operation of the hammer. The justification of the limit of the maximum length of the larger bent end of the support element is impractical. For each About a possible variant of the shock absorber, the length of the larger bent end of the support element has its maximum allowable limit. For example, when the row of holes in the bag is located in the same vertical plane, the diameter of which slightly exceeds the diameter of the supporting elements (the bent ends of the same diameter), the maximum length of the bent end practically does not exceed 60% of the height of the package in the unloaded condition.

Otherwise, the holes located above and below in the depressions of the corrugations partially overlap each other in the middle sheets of the bag, which is completely unacceptable because of the destruction of these sheets prior to operation. If the holes in the bag are arranged differently, for example, the holes made from above are placed in one plane and the lower holes are displaced to another vertical plane, or the diameter of the bent ends of the supporting elements is reduced (the diameter of the holes will decrease accordingly), then no overlapping of the holes on opposite directions will not occur, even if the holes are made through. In these cases (with through holes) the maximum length of the bent end can be 15-20% less than the height of the package in the unloaded condition, which excludes the possibility of contact between the bent ends and the intermediate plates with maximum elastic deformation of the package.

It is completely useless to use a shock absorber, which excludes the arrangement of three adjacent holes in the same vertical plane and allows you to make through holes in the package. The holes in the package are needed only to accommodate the long and short bent ends of the supporting elements. The purpose of the short bent ends is to securely fix the supporting elements themselves at the moment of the formation of a gap between the shock absorber and the woman, and the long bent ends prevent the separate corrugated sheets from turning around each other. And each of the mentioned bent ends reliably performs its functions at the specified minimum limits of their length, an increase in which leads to an unjustified increase in metal intensity, and the performance of through holes increases their number in each corrugated sheet. This is particularly reflected in medium corrugated sheets of the bag, in which the number of holes increases 17 times, i.e. with the bent ends of the minimum length and blind holes, it is sufficient to make only two holes in the middle sheets, and with the maximum possible length of the bent ends and through holes in the bag, their number reaches 34.

The bent ends entering the holes should not have sharp edges, but it is also not necessary that they end in a sphere. In order to avoid cutting or bending in

in the area of the holes of corrugated sheets which are accidentally shifted relative to each other, it is sufficient to round the end surfaces of the bent ends with a radius of 810 mm.

For normal conjugation of the middle part of the support element with the corrugation cavity and the bent end with the cylindrical surface of the opening in the package, the support element heated to the forging temperature should be bent without radius of the inner part of the bend followed by machining of this section until the shape of two intersecting at a right angle

cylinders of the same diameter.

The economic effect of using the proposed shock absorber is obtained by reducing hammer downtime caused by the replacement of shock absorbers and reducing the cost of manufacturing the shock absorbers themselves.

Claims (3)

1. The plunger damper of the hydraulic communication unit of the vertical loose hammer, containing a package of corrugated sheets with the same pitch of corrugations, supporting elements installed in the depressions of the corrugations between the package and the upper and lower intermediate plates, respectively, of which the first is connected to the supporting surface of the woman, and the second, to the supporting surface of the plunger, that, in order to increase reliability, the supporting elements are made in the form 1 figurative, in a package of corrugated sheets on the side of the upper and lower valleys, two rows of vertical holes are made with a depth of 1.15-1.2 times the length of the folded ends of the said brackets, with the supporting elements of these ends are installed in the holes of the package. 2. The shock absorber according to claim 1, from the section with the fact that at least two supporting elements located in the upper and lower depressions of the package, one of the bent ends is made longer than half the height of the package. 3. The shock absorber on PP. 1 and 2, characterized in that each intermediate the plate is made with two opposite edges, bent at a right angle in opposite directions, with the oppositely directed edges of the intermediate plates connected to the side surface of the package, and the oppositely directed edges respectively to the upper side of the female and the lower side to the side of the plunger. 1 u ZlbbZLl