SU929400A1 - Automatic line for making articles of the endless-track support roller type - Google Patents

Description

(54) AUTOMATIC LINE FOR MANUFACTURING

PRODUCTS OF TYPE OF SUPPORT ROLLERS

TRACTORS

one

The invention relates to mountains for stamping production, in particular to the transverse rolling of products such as support rollers of tractors.

A known automatic line for the manufacture of parts such as support rollers of tractors, comprising a loading device installed along the process and connected in series with each other kinematically and vehicles, a loading device, an inclined drive, a device for heating HDTV billets, a device for loading billets into a cross-rolling mill, an unloading device from the mill and quenching device 1.

However, this automatic line has low efficiency, increased energy consumption for heating, an insufficiently high quality of products and low productivity.

The purpose of the invention is to improve the quality of production of products, the performance of the line and reduce energy intensity.

To achieve this goal, the line is equipped with a mechanism for transferring blanks from the device for heating HDTV blanks to the device for loading blanks into the mill.

A device for heating HDTV billets is made in the form of a bushing inductor for sequential heating of two billets simultaneously, and a device for loading billets into a mill and an unloading device

5 from the mill are provided with grips for blanks and made in the form of carriages installed with the possibility of reciprocating movement, which ensure the transportation of blanks from the device for heating HDTV billets through the cross-rolling mill to the quenching device vehicle made in the form of a chain conveyor with reloaders.

In addition, the boot device and

15, the inclined accumulator is equipped with a lever slam-shut and with three working stops, two of which are designed to interact with the protuberances of the penultimate one before the slam of the support roller, and the third with the bottom of the last workpiece of the support roller.

Moreover, the heating elements of the inductor of the device for heating HDTV preforms are made in the form of electrically independent disks.

Moreover, the mechanism for transferring blanks from the device for heating HDTV blanks to the device for loading blanks into the mill has a carriage mounted with reciprocating movement with a semi-prismatic shimmer attached to it, equipped with a spring-loaded pawl and a lever for its forced rotation, and the device for heating HDTV blanks is fitted with half a mask coupled with the half-facet mechanism for transferring blanks from the device for heating HDTV blanks to the device for loading blanks into the mill, and the last nabzheno cam mounted to cooperate with said lever forced rotation of half-prism.

In addition, the vehicle's material handler of the quenching device is made in the form of two arcuate bars hinged with one arm on the side wall of the said vehicle with the semi-half fixed on the second end.

In this case, the loader is equipped with a controlled stop, made in the form of a spring-loaded rod with a flag.com command switch.

FIG. 1 shows an automatic line for the manufacture of products such as support rollers of tractors, a general view; in fig. 2 - receiving tray; in fig. 3 - cutter; in fig. 4 - pass inductor; in fig. 5 - loading device in the mill; in fig. 6 shows the mechanism for the forced transfer of heated billets from the device for heating HDTV billets to the charging device to the mill; in fig. 7 - loading device; in fig. 8 - controlled stop.

The automatic line for the manufacture of products such as support rollers (Fig. 1) contains a loading device, including a receiving tray 1 and a lift 2. The inclined storage device 3 serves to accumulate an excess of workpieces 4 in front of the device for heating HDTV billets, which consists of a body 5 and a through passage inductor b, hydraulics pusher 7. In case 5, devices for cooling water separation are placed, which serve to cool the current-carrying parts of the through-inductor and current-carrying busbars (not shown). The line is also equipped with a similar device for loading 8 workpieces into the mill and unloading devices with device 9 from the mill, as well as mechanism 10 for transferring the workpieces from the device for heating HDTV blanks to the device for loading workpieces into the mill.

The cross-rolling mill performs the main operation, rolling the treadmills and ribs on the workpiece support rolls and consists of a rolling stand 11, the work rolls of which are connected by cardan shafts 12 to the gear stand 13. The upper work roll is adapted to

working movement together with the cushion 14, in which it is fixed by means of a hydraulic cylinder 1.5. For clamping of the blanks during rolling, the centerers 16 serve. The quenching device contains three quenching plants 17 (only two are shown in Fig. 1) and equipped with a vehicle made in the form of a chain conveyor 18 with reloaders 19, 20 and 21. The chain conveyor is connected with hardening installations with branching conveyors 22-24.

All conveyors: primary 18 and branching 22 and 23 have the same speed of movement of the chains. The length of the branch conveyor 22 plus the length of the section of the main conveyor from its beginning to the reloader 19 is equal to the length of the branch conveyor 23 plus the length of the section of the main conveyor from its start to the reloader 20 and is equal to the length of the main conveyor from its start to the reloader 21. The branching conveyor 24 is made without a chain transmission, it is a gravity tray.

Such a construction of the transport device provides the same exposure of the products before quenching them in the quenching devices 17, which is very important from the point of view of high-quality and stable hardening of the treadmills and flanges of the tractor support rollers.

The automatic line also includes a capacitor bank, used to compensate for the reactive power of the device for heating HDTV blanks, electrical switchboards with electrical equipment and automatic control system, a hydraulic station serving to create oil pressure in the hydraulic cylinders of the line, a control panel serving to be placed on it. control buttons and control devices. A machine high-frequency converter or a thyristor high-frequency converter is used as a power source for the device for heating the HDTV blanks.

The receiving tray 1 and the inclined drive 3 (FIG. 2) are similar in design. They contain inclined guides 25, consisting of two corners, over which workpieces 4 are freely rolled. Blanks 4 are welded from two halves of forgings, having a roll-like appearance with projections E and depression F. From the bottom to the inclined guides through cradle 26 and the hinge 27 is attached to the hydraulic cylinder 28. The hydraulic cylinder rod 29, which is adjustable in length, acts through the hinge 30 on the lever locker 31, which in turn is fixed to the hinge 32 and the bracket 33 from the bottom to the inclined guides.

The lever cutter 31 (Fig. 3) is a lever with three working stops. The stops G act on the projections E of the penultimate blank located on the inclined guides, and the stop H on the depression F of the last blank located in the inclined guide. The inductor 6 (FIG. 4) is made of four electrically independent heating discs 34-37, which include primary windings and secondary windings. The primary windings of each heating disc are connected to a portion of the voltage of an HDTV source. Heating discs are interchangeable. The length of each heating disk is made along the length of the projections of the workpiece with some overlap, because according to the requirements of the technological process, only the protrusions of the workpiece are heated to a depth of 30-40 mm. The hollows of the billet must remain cold before rolling. The heating discs are installed from the center of the projections of the blanks, which contributes to the optimal concentration of electromagnetic fields in the zones of the blanks to be heated. The heating discs 34 and 35 heat the first blank as they move, the heating discs 36 and 37 heat the second blank. All heating discs are insulated from each other and mounted on an insulating base 38, which, in turn, is fixed to the housing 5 of the device for heating HDTV blanks. The tubular guides 39 are made of stainless steel hollow and cooled with running water. They are mounted on insulating racks 40. The tip of the slider 41 of the hydraulic tappet 7 of the device for heating high-frequency workpieces, acting on the workpiece located on the tubular guides outside the inductor, provides cyclic pushing of the workpieces through the inductor and unloading the products heated for rolling. The device for loading the blanks into the mill 8 and the unloading device from the mill 9 (Fig. 5) are similar and consist of rods 42, through which the carriage 44 is moved by means of the rollers 43, carrying the body 45 on itself. The unloading device from the mill is provided with a gripper 46 serving to hold the blanks during their transportation. The rods 42 are on the one hand secured to the rack 47, and on the other hand to the rolling stand (not shown). The end part of the housing 45 is made in the form of a half-prism (surface L). On the front part of the body of the device for loading workpieces into the mill, there is a protruding cam M. It serves to reset the moving part of the mechanism for transferring the workpieces from the device for heating HDTV workpieces to the loading device into the mill. The discharge device from the mill is not equipped with such a cam. The gripper 46 is actuated by the hydraulic cylinder 48, which is fastened to the bracket 50 through the hinge 49. The hydraulic cylinder rod 51, acting on the lever 52, causes the gripper 46 to pivot about the axis 53. The lever 52 is provided with a flag that acts on the electric sensor 54 when the gripper is opened . The grip of the workpiece is produced by the surfaces K and L. The mechanism for forcing the heated billet from the device for heating the HDTV billet to the loading device in the mill 10 (Fig. 6) consists of a carriage 55, which is movable with the help of rollers 56 along shaft 57. The hydraulic cylinder 58 serves to force the carriage to move, its scraper 59 is connected to the carriage through a swivel 60. A fixed semi-prism 61 is mounted at the exit of the inductor, near the last heating disc 37 (shown by thin lines in Fig. 6). The trolley carries the second semi-prism 62, which is mounted on the bracket 63. The bracket 63 is mounted on the hinges 64 so that it can be rotated loading the blanks into the mill (the direction of loading the blank into the mill is shown by the arrow). The semi-prism 62 on the trolley is set at such a height that when the trolley approaches the inductor, it with a fixed semi-prism 61 forms a tray (consisting of surface N on semi-prism 62 and surface O on fixed semi-prism 61) capable of receiving the heated billet from the inductor. FIG. 6 also shows the front part of the housing of the device for loading the blanks into the mill 45 without gripping. It is also designed as a half-prism (surface L). In the initial position of the device for loading the blanks into the mill, the surface L of the end part of the body forms a tray with the surface N of the semi-prism 62 mounted on the trolley capable of holding the blank 4 (shown in dotted lines in Fig. 6). In the same position of the device for loading the blanks into the mill, the front part of the body 45 is a continuation (with a small gap) of the fixed semi-prism 61, i.e. surface L is a continuation of surface 0. A semi-prism 62 mounted on a trolley is provided with a spring-loaded 65 dog. A spring-loaded dog 65 is freely recessed by the workpiece 4 during the course of the carriage 55 to the inductor, while the workpiece acts on the surface P of the dog. When the carriage 55 retreats to its original position, the surface Q of the dog rests against the protrusion of the workpiece from the inside and the workpiece moves with the carriage. The semi-prism 62 mounted on the trolley is held in the initial position by the lever R, which is provided with the bracket 63. The semi-prism is held in the initial position by the interaction of the cam of the front part of the device for loading the blanks into the mill M and the lever R. in the countries ahead, while loading the blanks into the machine, the cam M and the lever R are disengaged, and the lever 63 together with the half-impact 62 fall onto the stop 66, the straight path of the workpiece 4 is empty. During the course of the device for loading workpieces back to the mill, during idle speed, the cam M. and the lever R come into intermeshing and the lever 63 together with the half-prism 62 comes to B the initial state. On the fixed semi-prism 61, there is also a cam similar to cam M on the front part of the device for loading workpieces into the mill, which is a continuation of cam M and serves to hold lever 63 and half-prism 62 in the initial position when the carriage 55 approaches the inductor.

Reloaders 19-21 (Fig. 7) are embedded in a chain conveyor. 18. It consists of two arcs 67, the ends of which, through hinges 68, are seated on the right (in the direction of movement of the rolled products) side wall of the chain conveyor 18. The direction of movement of the rolled product 69 in FIG. 7 is shown by the arrow. The other ends of the arcs carry the half-prism 70, which is the geometric continuation of the left (along the movement of the rolled products) side wall of the chain conveyor 18. On the half-prism 70, a half-guide 71 71 is installed, which is a continuation of the left-wing 72 chain trance 1Orter. The hydraulic cylinder rod 74 74 is connected through the hinge 70 to the hüluprizm 70. The hydraulic cylinder 75 is fastened through the hinge 76. The stroke length of the hydraulic cylinder 75 rod is designed to ensure that the arches 67 are rotated around the hinges 68 to such an extent that the rolled product 69 is based at the same time on the right guide 77 of the chain conveyor and on the semi-prism 71 simultaneously, freely rolled between the arcs 67 to the inclined receiving tray 78, the branching conveyor. A plate closed chain 81 is installed between the right side wall 79 of the chain conveyor and the left side wall 80 of the chain conveyor, which is in constant motion. On the plate-shaped closed circuit 81, pushing cams 82 are installed at regular intervals, which serve to move the rolled products 69 along the chain conveyor guides. A groove X is made in the right hand-held chain conveyor 18, in which a controlled stop 83 is laid.

A controlled stop serves to selectively stop the rolled product 69 in the material handler. Controlled stop (Fig. 8)

consists of a rod 84 with a tip 85, made of heat-resistant metal.

The rod 84 is placed in the housing 86 with the possibility of free axial displacement and is spring-loaded in it by the spring 87.

The housing 86 through the hinge 88 is attached to

the wall of the groove X. The rod 84 is equipped with a flag 89 which through the groove Y, made in the housing 86 extends beyond it. In the rear position of the rod 84, the flag 89 acts on the electric sensor 90.

0 The electric sensor 90 is fixed to the plate 91, which is fixed to the housing 86. The cylinder of the hydraulic cylinder 93 is attached to the housing 86 via a swivel 92. The hydraulic cylinder 94 is fixed through a hinge 95 The stroke of the hydraulic cylinder 93

 is selected such that when the rod leaves the hydraulic cylinder, the body 86 rotates on the hinge 88 to such an extent that the tip of the rod 95 ups into the end face Z passing along the conveyor chains of the rolled product 69. The direction of movement of the rolled product 69 along the chain conveyor guide is shown an arrow.

Automatic line works as follows.

Billets 4 from the previous mechanism are placed on the receiving tray 1 (Fig. D). The blanks 4 are held on the inclined guides 25 by the stop H of the shutter 31. In this position, the hydraulic cylinder bushing 29 is extended from the hydraulic cylinder 28. The signal for pulling the hydraulic cylinder bushing 29 into the hydraulic cylinder 28 is the elevator cradle in the lower position and the absence of a blank 4 in it that fixed by a limit switch. When the hydraulic cylinder 29 is retracted into the hydraulic cylinder 28, the hydraulic cylinder rod 29 through the hinge 30 acts on the slam-shutter 31 and rotates it relative to the hinge 32 on the bolster 33. At the same time, the hydraulic cylinder 28 can swing relatively

 the hinge 27 on the bracket 26. Turning, the slam-shutter 31 releases the last workpiece and it rolls into the cradle of the elevator. In this case, the stops G of the shutter 31 begin to act on rolling

5, surfaces E of the last but one blank and keep it and the entire column of blanks located on the inclined guides 25 from rolling. The next moment, the rod of the hydraulic cylinder 29 again leaves the hydraulic cylinder 28, with the stops G ogre ° cathele 31 releasing the penultimate workpiece and the whole column of blanks rolling to the stop H of the cutter 31. The lift 2 of the workpiece 4 is fed to the hopper 3, rolling down the hopper and through the cutter coaxially with the inductor 6. The rate of operation of the device’s pusher for heating HDTV 7 blanks sets a time relay, based on the time required

for optimal heating of the workpieces in the pass through inductor 6.

The optimum residence time of the blanks 4 in the bushing inductor 6 is determined by the need to heat the blanks to 1150-1250 ° C to a depth of 35-40 mm from the surface of the blank. This time is chosen empirically. For example, for rolling tractor support rollers, the rate of delivery of blanks from a through inductor is 72 seconds, with a total time spent for the workpiece in the inductor 144 seconds.

After a certain period of time, the rod of the hydropusher 7 begins to move forward and, with its tip 41 (Fig. 4), pushes the workpiece lying on the tubular guides outside the bushing, which in turn pushes the column of billets in the bushing. The pushed billet takes up a position under the heating discs 34 and 35, and the billet that was previously at this place takes up a position under the heating discs 36 and 37. The blank that was previously under the heating discs 36 and 37 leaves the inductor, where it is picked up by the mechanism for forcing the blanks from the device for heating the HDTV blanks to the loading device in the mill 10. The stroke of the hydropusher 7 forward is detected by an electric sensor, which is affected by a flag. At the next moment, the hydraulic tappet wheel retracts and a new countdown of the exposure time in the billet through billet of the preforms for heating begins.

Simultaneously with the signal to the forward stroke of the hydropolator (Fig. 1) forward, a signal is received to the stroke of the hydraulic cylinder of the workpiece feeding mechanism from the device for heating HDTV to the loading device to the mill. Being in the rear initial position, the boot device into the machine with a cam M, which is provided with the front part of the boot device body in the mill 45 (Fig. 6), holds the arm 63 with half-fit 62 by hooking the lever R. And in this position when the signal arrives the cart 55, due to the operation of the hydraulic cylinder 58, begins to move toward the flow inductor. In this case, a semi-prism 62 mounted on the trolley 55 will take its place opposite to the stationary semi-prism 61 and their surfaces O and N constitute in this case a tray, to which the workpiece emerges, is pushed out of the inductor. In the front position of the trolley 55, the bracket 63 also does not disappear, since the fixed semi-prism 61 also has a cam, which, by configuration, repeats the cam of the M front part of the loading device into the mill and is its continuation. A billet is heated on a tray made up of O and N surfaces from the bushing inductor. The front thickened part of the workpiece thus acts on the surface P of the spring-loaded dog 65 and sinks it. After passing the thickened part of the workpiece through the dog 65, it is released and takes up its original position. The signal for moving the carriage 55 back to its original position is the presence of a hydrticolk rod in the forward position. When the signal is received, the hydraulic cylinder rod 59 is retracted into the hydraulic cylinder 58 and the carriage 55 on the rollers 56 along the bolts 57 returns to its original position. At the same time, the spring-loaded dog 65 with the surface Q pulls the workpiece 4 due to the fact that the surface Q abuts against the thickening of the workpiece from the inner side. The initial position of the carriage 55 is fixed by an electric sensor and this is a signal for the operation of the hydraulic cylinder of the gripper 48. At this time, the workpiece is in the tray formed by the surfaces of the N semi-prism 62 mounted on the carriage 55 and L of the front part of the loading device in the mill. When the scraper 51 is pulled into the gripping cylinder 48, the lever 52 rotates about the axis 53 and the gripper locks the device into the mill 46 with its K surface

5 blank. At the same time, it is held by the surfaces K and L. When you turn, the lever 52 ceases to act on the electric sensor 54 and this is the signal for the actuation of the hydraulic cylinder for the load device to the mill. When the loading device travels forward to the mill, the front part of the loading device body to the mill 45 pushes the bracket 63 and it, turning relative to the hinges 64, falls on the stop 66, releasing the stroke for the loading device to the mill together with the workpiece. The loading device in the mill moves forward to a strictly defined position. In this position, the axis of the transportable workpiece must coincide with the axis of the centering device 16: | preparations.

0 The workpiece 4 is freed from being gripped and the loading device in the mill is returned to its original position. When returning the boot device to the mill to its original rear position, cam M on the front part

5, the loading device in the mill is hooked onto the lever R of the bracket 63 and the bracket 63, together with the half-rim 62, is restored to its original position and held therein by the mutual engagement of the cam M and the lever R.

When the loading device is withdrawn, a command is sent to the mill in the initial back position to feed the upper girdle to the workpiece and the roller profile is rolled. The rolling and rolling time of the finished product profile 69 is set by a time relay.

Vygruznuyu vystupn to fit the vacated nakatniki rolled product

The roystvo from camp 9 and transfers the rolled product; -; on a chain conveyor 18.

From the gakhvat of the unloading device from the mill, the rolled product falls out and falls into the guides 72 and 77 of the chain conveyor. Here, the product moves along the guiding pushes 82, fig. 7, which are mounted on a continuously moving plate-shaped closed circuit 81. From the chain conveyor 18, the rolled products are transferred to the branch conveyors 22, 23, 24, FIG. 1. The overloading of rolled products is carried out by reloaders 19, 20, 21. One or another reloader operates according to the presence of rolled products in quenching devices 17. E1SLI all three quenching devices are free, then the reloader 19, which is first on the chain conveyor 18 in the course of movement of the rolled products on it. The loader 19 overloads the rolled product to the branch conveyor 22, along which the rolled product enters the first quenching device 17. The second rolled product moves along the chain conveyor no earlier than 72 seconds (the time is set by the rate of delivery of heated billets from the inductor), and this time is not enough to release the first quenching device from the rolled product. Therefore, the rolled product in this case passes through the chain conveyor 18 through the first material handler 19, and the second material handler 20 comes into operation. The material handler 20 overloads the rolled product to the branch conveyor 23, through which the rolled product enters the second quenching device 17.

The third rolled product passes through the chain conveyor 18 through the first and second material handlers 19 and 20, and the third material handler 21 enters the work. The material handler 21 loads the rolled product to the branch conveyor 24, through which the rolled product enters the third quenching device 17.

The fourth rolled product, but in time, is already ready to accept the first quenching device, and therefore the first material handler 19 comes into play along the way.

The work of loading cranes is carried out as follows.

If the quenching device that is serviced by the material handler is free of the rolled product, this is the signal for actuation of the hydraulic cylinder 94 (Fig. 8), controlled by the stop 83 (Fig. 7). The hydraulic cylinder 94 extends the cylinder of the hydraulic cylinder 93 and the latter, acting on the housing 86 through the hinge joint 92, rotates the housing 86 relative to the joint 88. The control stop 83 emerges from the groove X in which it is laid and is ready

chucking the rolled product moved along the chain conveyor. The rolled product 69, moving along the guides with its end surface Z, is located on the tip of the rod 85 (Fig. 8). At the same time, the brush 84 ' is embedded in the body 86, and the rolled product is stopped in the reloader. The cam 82 slips under the rolled product. The flag 89 acts on the electric sensor 90, which is a signal for the operation of the hydraulic cylinder 75.

0 The hydraulic cylinder rod 74, the output of the hydraulic cylinder, lifts the semi-prism 70 and rotates it on the arches 67 relative to the hinges 68. At the same time, the rolled product based on the semi-prism guide 71 and the right-hand 77 conveyor chain of the rolled product rolls between the arches 67 to the inclined receiving tray 78. conveyor belt. Thereafter, the loader comes to its original position and the controlled stop 83 is placed in groove X.

The following rolled products pass through the material handler until the next material handler until the quenching device serviced by the material handler is freed from the rolled product. By the branching transporter, the rolled product rolls on its flanges along the rails. The branch conveyor circuit is closed and in constant motion.

0 In quenching devices, quenching of treadmills and support roller flanges takes place, after which the finished products are rolled out into containers.

An automatic line can significantly improve the quality of heat treatment.

5 by ensuring that the blanks processed on it have the same exposure before quenching, including heating in one inductor, the same transfer time for all the blanks from the inductor to the inter-roll space, the same time of rolling and transferring the blanks from the multi-roll space to the quenching devices, to increase productivity by increasing the rate of issue of heated billets from the inductor and ensuring the forced

transfer of blanks, reduce energy consumption and labor intensity due to more optimal use of HDTV sources and reduction of service personnel.

Claims (3)

1. Automatic line for the manufacture of products such as support rollers of tractors, containing installed along the process and connected in series with each other kinematically and vehicles loading device, inclined drive, device for heating billets TV-H, device for loading billets in the cross-rolling mill , the unloading device from the mill and the quenching device, characterized in that, in order to improve the quality of the production, the productivity of the line and reduced and energy consumption, the line is equipped with a mechanism for transferring blanks from a device for heating HDTV blanks to a device for loading blanks into a mill, a device for heating HDTV blanks is designed as an inductor for sequential heating of two blanks simultaneously, and a device for loading blanks into a mill and The unloading device from the mill is equipped with grips for blanks and is made in the form of carriages installed with the possibility of reciprocating movement, ensuring the transportation of blanks from troystva for heating the preforms through HDTV cross rolling mill to a vehicle tempering device, designed as a chain conveyor with reloader mi. 2. Lines according to claim 1, characterized in that the loading device and the inclined storage unit are equipped with a lever cutter with three working stops, two of which are designed to interact with the last but one protuberance of the support roller pre-cutter, and the third with the bottom of the last workpiece of the support roller. 3. Lines according to claim 1, characterized in that the heating elements of the inductor of the device for heating the HDTV preforms are made in the form of electrically independent, interchangeable heating discs. 9 0 4. Lines according to claim 1, characterized in that the mechanism for transferring the workpieces from the device for heating HDTV blanks to the device for loading workpieces into the mill has a carriage mounted with reciprocating movement of a carriage half-mounted with a spring-loaded dog and it is forced to rotate it, and the device for heating HDTV blanks is equipped with a half-lens, joined with a semi-wave of the mechanism for transferring blanks from the device for heating HDTV blanks to the device for loading blanks in the mill, and the latter is equipped with a cam installed with the ability to interact with the broken arm of the forced rotation of the half-prism. 5. Lines according to claim 1, characterized in that the loading device of the vehicle of the quenching device is made in the form of two arcuate planks hinged with one end on the side wall of the said vehicle with the half-fastened at the other end. 6. Lini on PP. 1 and 5, characterized in that the material handler has a control abutment, made in the form of a spring-loaded rod with a command switch flag. Sources of information taken into account during the examination 1. Automated line type HC-1 3. Developed Rubtsovsk Design Institute of Tractor Engineering, 1973. 25 is Z7 Fig.Z / T / / A. / / / / / g + yj SO ti3 8 fZ f3 Fi. S s