JPS591125B2 - Metal billet rolling method and rolling machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to metal processing, and more particularly to a method and a rolling mill for rolling metal materials in a single pass to obtain rolled products from ferrous, non-ferrous metals or alloys. It is related to.

The present invention can be advantageously used to roll billets of low ductility and difficult to deform metals and alloys.

Castings, powder moldings, preformed billets, etc. can be used as starting materials.

For example, reducing a metal billet by processing rolls to create a deformation cone having a length along the axis of the billet that is significantly greater than the length of the deformed zone shaped in the billet by each processing roll at each given moment during its processing. As transition part (trans□1tional 5
A method of rolling a metal billet in a single pass is known in the art, which consists in alternating the axial feed of the processed billet and said reduction process during one step of rolling. ing.

The deformation cone means the transition from the initial dimensions of the billet to the dimensions of the finished product; in other words, the length of the billet from the initial dimensions of the billet to the dimensions of the finished product. It means a part whose cross-sectional area changes (decreases) in the direction.

It consists of a support frame having a guide passing axially along the billet to be rolled, supporting a roll housing which is transmission connected to the mill drive for reciprocating the stand inside the guide during rolling. A rolling mill for carrying out the method for rolling metal billets described above is also widely known.

A pair of variable cross-section processing rolls are supported in a roll housing, the axis of which is disposed symmetrically with respect to the billet axis and in a plane perpendicular to the billet axis.

Each rolling mill includes a feeding device supported on the side where the billet enters the work rolls and transmission connected to the rolling mill drive for feeding the billet in the axial direction.

Such rolling mills are typically used to roll hollow tubular billets supported on a mandrel, each billet having a
The work surfaces of the work rolls are reduced as they move along the billet axis and contact the billet with simultaneous rotation of each work roll about the work roll axis and the work surfaces of the work rolls approach each other.

The reduction of the billet is repeated with the axial feed through one pass.

The main drawback of the prior art re-rolling process and the two-high rolling mills implementing this process is that the deformation of the metal of the billet being rolled results in uniaxial compression, thus reducing the ductility of the metal. That's true.

Moreover, the reduction processing in such a rolling mill is performed unevenly on the circumference of the billet, which impairs the workability of the billet material.

Another drawback of prior art two-high rolling mills is the large difference in speed at various locations in the pass of the work rolls, which reduces the elongation capacity in the pass and leads to its rapid wear.

The above drawbacks are even more acute in the rolling of solid billets of low ductility metals and alloys, in which case prior art two-high rolling mills become impractical.

The rolling of the end portions of hollow billets in such rolling mills is only possible by inserting a mandrel therein, and the processing of solid billets is impracticable in such rolling mills. It should be noted that this is possible.

Also known in the prior art are rolling mills in which the reduction is carried out by two pairs of non-driven working rolls 5 each of which is operated as a unit moved in time phase with respect to each other (for example, US Pat. No. 3,439,519). , classification 72-189).

In such rolling mills, the shaft of each work roll is journaled in a lug attached to a long member, one end of which is
It surrounds and supports a rotatable eccentric via a drive, and the other end is rotatably connected to a link, which is rotatably connected to a projection of the rolling mill frame.

The eccentrics intended to impart percussive movements to the elongated members of each pair of work rolls are provided out of phase in the direction of the pass.

Movement of the eccentric causes each work roll to approach the pass line in a curved path and retreat from the pass line in a second curved path.

Therefore, the centerline of either work roll moves in a closed curved path.

When the work roll is supported to rotate freely and is not driven by the rolling mill prime mover, the work roll is free to rotate about its axis, and when the work roll is in contact with the workpiece in its path, Limiting rotation through an arc of less than 360° in a direction determined by the friction between the material to be reduced and the material to be processed and the motion exerted on the workpiece by the rolling mill's feed and pull devices. be done.

During the return movement of the axis of the work roll along the curved path, the work roll is returned to its initial position (for example by a spring).

In such a rolling mill, compared to the above two-high rolling mill,
The speed difference around the circumference of the work roll path is reduced and therefore the work roll wear is reduced.

Therefore, the reduction around the cross-section of the billet is more uniform than in a two-high rolling mill.

However, the main disadvantage of two-high rolling mills, namely the shrinkage of the billet in the deformation zone due to axial compression, is also present in this type of mill.

Among the drawbacks of prior art rolling mills with two pairs of work rolls that are spaced apart along the pass line, as shown by metal deformation studies, the displacement of the work rolls causes the deformation on the cross-section of the billet to This results in considerable non-uniformity of the material and impairs billet quality, especially billets made from low ductility metals and alloys.

Other drawbacks of prior art rolling methods and rolling mills are further described.

Significant spreading of billet metal reduces its elongation.

Reduction of the billet by non-driven rolls results in the development of tensile forces.

The curved shape of the travel path of the drive roll causes undulations to be formed in the billet after rolling.

Disadvantages also exist when the eccentric is driven by a bevel gear which has a relatively short life when operating under heavy loads in close proximity to hot metals.

This also affects the reliability of the spring-loaded device for rotation of the work roll during the return movement of the work roll.

The aim of the invention is to eliminate the above-mentioned drawbacks.

The present invention improves the workability of billet metal in the deformation zone of billet metal during shrinkage by reducing billet elongation rate and increase as well as billet spreading in a single pass, improving product quality; In particular, a method and a rolling mill for rolling metal billets in a single pass are provided that can improve the quality of products from low ductility metals and alloys and increase rolling production efficiency.

The above purpose is to reduce the metal billet by processing rolls, and during its processing, the billet is reduced almost uniformly over its entire circumference, and the deformation area formed by all processing rolls is reduced by one processing roll. limited throughout the reduction period within the length of the formed deformation zone;
A transition section is formed in the billet as a deformation cone having a length along the axis of the billet that is significantly longer than the length of the deformation zone formed in the billet by each working roll at each given moment, and rolling In a method for stepwise rolling of metal billets in which axial feeding and said reduction work are alternately carried out in one process, during the deformation process of said bit 1 over the entire length before each reduction process, said billet undergoes one process. Tilted alternately in opposite directions over half the angle α between one plane perpendicular to the axis 0 of the roll 2 and another plane perpendicular to the axis of the adjacent work roll, the sizing of said billets is determined during the reduction period. This is achieved by a method of stepwise rolling of metal billets, which is characterized in that it begins at the end of and ends simultaneously with the completion of the reduction of the transition section.

The term "deformation zone" means a portion of the deformation formed in the billet by one working roll at each given moment.

The above method improves the workability of billet metal.

This is because the deformation zone formed by all working rolls is limited within the same length of the billet by the two axial compression effects.

The above feature is that the deformed areas are spaced apart in the axial direction,
Experience has shown that it eliminates material non-uniformity in deformation that occurs across the billet, reduces shear deformation, and eliminates metal discontinuities.

Furthermore, bringing the deformation zones together axially along the billet makes it possible to reduce the spreading of the metal,
Assist billet elongation in a single pass.

During the axial feeding of the billet to be processed, the billet is tilted alternately in opposite directions over half the angle between the two planes passing through the axis of the billet, so that one of said two planes is Advantageously, it is perpendicular to the axis of the work roll and the other plane is perpendicular to the axis of the adjacent work roll.

If the billet being machined is tilted during axial feed,
To create a smooth surface on a billet coming out of a processing roll without creating fins or bulky bulges.

Alternating the direction of billet inclination during axial feeding prevents billet twisting.

At the end of each reduction cycle, the processed billet is preferably si-geed to prevent undulations on its surface.

The above object also provides a metal billet rolling machine for carrying out the method according to the invention, namely a frame having a roll housing running parallel to the axis of the billet to be processed and supported on a guide member; , supporting a variable radius work roll that is transmission-coupled to a rolling mill drive for reciprocation on the guide member during rolling and is disposed symmetrically with respect to the axis of the billet; a feeding device for feeding the billet in the axial direction; the feeding device is supported by the frame on the side where the billet enters the processing roll, and is transmission-coupled to the rolling mill drive device; In a billet rolling mill, the roll housing accommodates at least four actively rotatable work rolls, the geometric rotation axes of the work rolls being located in a plane perpendicular to the axis of the billet. This is achieved by a metal billet rolling mill characterized by

The structure of such a rolling mill makes it possible to limit the deformation zone formed in the billet rolled by all work rolls to within the deformation zone formed by one work roll at each given moment, thereby making the billet The deformation results in biaxial compression, resulting in better workability of the billet metal and, as a result, improved product quality.

Of note, the active rotation of the processing rolls improves its operating conditions and makes it possible to apply a preset compressive force (thrust) axially along the billet to be processed, making it possible for rolling The use of non-driven processing rolls exerts an axial tensile force on the billet.

The relative position of the working rolls and the billet to be worked will also be very constant at each instant of rolling.

In particular, this makes it possible to use a working roll working surface of a given shape in the sizing section.

Each work roll is preferably formed as a sector in a plane perpendicular to its geometric axis of rotation, the axis of the sector being arranged eccentrically with respect to the work roll's geometric axis of rotation and having a variable radius of curvature. A sizing section, which is located on the side of the billet coming out of the processing rolls and which matches the curved section, has a sizing section whose surface has all generatrices at the end of the processing movement of the processing rolls. The length t of the sizing section in the axial direction of the billet is defined by the axial feed of the billet for one process width as S, and the elongation rate of the billet in a single bath as λ. In this case, it is determined from the formula t≧S·λ.

The above configuration is a preferred embodiment, in which the working rolls of the rolling mill have a sector shape in a plane perpendicular to the geometric rotation axes o, o'.

The simple shape of the working surface makes it possible to manufacture rolling mill work rolls without special metal-cutting machine tools (i.e. other complex manufacturing techniques).

Moreover, the curved section AB and the sizing section BC connected thereto make it possible to reduce the billet above the deformation cone, and the formation of the finished profile with shape and cross-sectional dimensions (sizing) remains unchanged in length. It is done as follows.

First, the billet is reduced on a deformation cone, and then, before the above steps are completed, the sizing section of each work roll is actuated.

The above two steps are completed simultaneously.

No additional movement is imparted to the working rolls for sizing.

The above action is carried out by placing the sizing part of each work roll parallel to the rolling axis at the end of the formation of the deformation cone.

Since no additional movement is imparted to the work rolls to size the finished product, the efficiency of the rolling mill is improved and dynamic loads are reduced, which considerably improves the durability of the part.

S·λ in the above formula indicates the product of S and λ.

That is, the symbol ゛°·'' indicates multiplication. Therefore, the above equation indicates that t is greater than S·λ or that t is equal to S·λ.

When the axial feed of the billet is S, the elongation rate of the billet is denoted by λ, and this elongation λ can be measured as the ratio of the cross-sectional area of the billet before deformation to the cross-sectional area of the billet after deformation.

The axial feed S of the billet indicates the length that the billet advances axially toward the rolls after each pass through the rolling stand, and is measured in meters or millimeters.

The length of the sizing section BC is measured in meters or millimeters.

With such a construction of the working roll, the dimensions of the roll housing can be reduced and the whole becomes more compact.

In addition, the sizing section of the processing rolls that defines the final dimensional cross-section of the billet prevents the surface of the billet being processed from having undulations and, in combination with the slope of the billet, creates a smooth surface free from fins and bulky bulges. A surface is obtained.

To create sized portions of the billet that overlap each other, the length of the sizing section of the work roll along the axis of the billet is also greater than the length of the billet at exit from the work roll in a single pass. and this length depends on the axial feed of the billet and its elongation rate.

The construction of the processing roll according to the invention makes it possible to reduce its rotation angle and shorten the transition distance of the roll housing, so that the axial feed of the billet is reduced over one stroke of the roll housing. This improves the quality of the deformed metal in the billet without reducing the productivity of the rolling mill as a whole.

The billet metal after such rolling is dense and
The fineness of the particles also improves their mechanical properties and durability.

All of the above becomes particularly important in the rolling of metal and alloy billets with low ductility and resistance to deformation.

The portion of the work roll forming the curved and sizing portions is preferably made removable and comprises a replaceable insert of a wear-resistant, fire-resistant alloy; the remaining portions of the work roll are provided with suitable recesses. and a screw hole for attaching an insert here.

Inserts extend the life of processing rolls.

According to another embodiment of the invention, the positive rotation of each work roll about its axis is effected by a rocker rod, one end of which is rotatably connected to the work roll, and the other end of which rotates all the work rolls. It is rotatably connected to a support member common to the moving rod and is attached to the frame on the side where the billet emerges from the work roll.

The rotation of the processing rolls using a rocking rod operates under heavy loads and high temperatures compared to the processing roll drive systems in cold tube rolling mills and multi-roll rolling mills that use gear transmissions to drive the processing rolls. Improve the reliability of processing roll drives.

Furthermore, with this structure of the work roll drive, the billet metal pressure applied to the work roll is not directly transmitted to the parts of the roll housing drive, but is primarily transmitted through the rocker rod and the work roll shaft. Absorbed.

Each rocker bar can be bifurcated at one end, thereby accommodating a corresponding work roll at the pivot joint.

This construction makes the rocker rod stronger and much more reliable under the heavy loads exerted on the processing rolls.

The support member is preferably formed of a hollow cylindrical casing supported on the same axis as the billet, and has a through hole provided in both end walls of the casing on the same axis as the billet and receiving the guide member. , the guide member is formed as a tube for the bit passage and is rotatable about the axis together with the billet by means of an auxiliary device for axially feeding and tilting the billet in the support member. a clamp supported in the opening of the guide member for clamping the billet to the guide member;
a linkage device for transmission connection of the outlet end of the guide member to the roll housing for axial movement of the guide member; and a piston rod and support member rotatably connected to the guide member for rotating the guide member. and an air cylinder device having a cylinder rotatably connected to the air cylinder.

The installation of the rolling mill according to the invention consists of an auxiliary and tilting device supported behind the roll housing along the pass line and operating synchronously with the billet axial feed sump device on the side where the billet enters the working rolls. , making it possible to process the billet over its entire length in a single pass.

The structure of the auxiliary device for axially feeding the billet and tilting the billet on the side where the billet emerges from the processing rolls allows the billet to pass freely through the guide elements during the reduction process and Ensure axial feed and at the same time tilt the billet at the end of the return movement of the roll clamp.

The force-transmitting connection between this device and the mill stand housing creates a reliable synchronization of its operation with that of the mill stand.

Each clamp for clamping the billet in the guide member may consist of two jaws supported on opposite sides of the billet in a coaxial guide provided in the opening of the guide member, one jaw being attached to the guide member. It is fixed to the piston rod of another air cylinder arrangement supported outwardly on the member, the other jaw being connected to a dowel adjustment screw for adjusting the clearance between the two jaws.

Such a ramp makes the application of the clamping force to the billet smooth during its clamping.

The invention will be explained below with reference to specific embodiments shown in the drawings.

The method according to the invention for rolling a metal billet 1 in a single pass (FIG. 1) is based on the reduction of the billet by means of work rolls 2, together with the axial feed of the billet 1 being worked during the rolling process S. Repeat the reduction.

During the intermittent reduction of the billet 1, the transition section of the billet 1 is significantly longer than the corresponding length m of the deformed zone formed in the billet 1 by each working roll 2 at each given moment.
The billet is formed into a deformed cone having a length M along the axis of .

According to the invention, the billet 1 to be processed is uniformly reduced approximately over its gold circumference, and as shown in FIG. The deformation area formed by the processing rolls 2 is limited within the length m of the deformation area formed by one processing roll 2.

Therefore, at each given moment, the deformation of billet 1 is
It is carried out according to biaxial compression, thus improving the ductility of the material of the billet 1 and improving its quality.

According to the invention, during its axial feeding, the billet 1 has a 1
and the other plane perpendicular to the axis of the adjacent working rolls 2 and passing through the axis of the billet 1 (alternately inclined in opposite directions over half of FIG. .

In this example, the angle α is equal to 90° and the billet 1 is tilted by 45°.

At the end of each reduction step, the cross-section of the billet 1 is sized and combined with a simultaneous tilting of the billet, resulting in a billet 1 with a smooth and correct surface without fins and bulky bulges.

Further advantages of the method of rolling a metal billet 1 in a single pass according to the invention will become apparent from the description of the operation of a rolling mill implementing this method.

The rolling mill according to the invention for carrying out the method of rolling a billet in a single pass comprises an integral motor running parallel to the axis of the billet 1 to be processed and electrically connected to a rolling mill drive, e.g. an electric motor 6. A frame 3 (with a guide 4 supporting a target roll crank 5 and adapted to reciprocate the roll crank inside the guide 4 during rolling)
3 and 4).

The force-transmitting connection between the shaft of the electric motor 6 and the roll crank 5 is provided in this embodiment by reduction gears in the form of two crank units 7 and two spur gear transmissions 8.

The opening provided in the center of the roll housing 5 has a geometric rotational axis 0.0' (the first
and 4) are supported in one plane perpendicular to the axis of the billet 1.

The working rolls 2 are arranged in pairs symmetrically with respect to the axis of the billet 1.

In this rolling mill, as shown in Figures 4 and 5,
The rotational axes 0, 0' of one pair of processing rolls 2 extend substantially horizontally, and the axes of the other pair extend substantially vertically.

Each work roll according to the invention has an axis arranged with an eccentricity e (FIG. 4) relative to the geometric axis of rotation O of the work roll 2 in a plane perpendicular to its geometric axis of rotation O. It is formed in the shape of a sector of a circle, and a curved portion AB having a variable radius of curvature ρ is formed on the surface of the processing roll.

The curved section AB coincides with the sizing section BC on the side where the billet 1 emerges from the working roll 2, and this sizing section is such that all generatrix lines of its surface lie on the billet 1 at the end of the working movement of the working roll 2. It is formed to run parallel to the axis of the

In this particular embodiment, where the billet 1 is octagonal in cross-section, the sizing section BC of the working roll 2 is flat.

The length t of the sizing portion BC in the longitudinal direction of the billet 1 is determined from the formula t≧S・λ, where S is the axial feed of the billet 1 during one process and λ is the elongation rate of the billet. I can do it.

The curved section AB and the fixed size section BC (which are combined,
The part of the working roll 20 (which forms the working surface of the working roll 2 in contact with the billet 1 to be worked) is made removable by a replaceable insert 9 (FIG. 3) of a wear-resistant, refractory alloy.

The other parts of the work roll 2 have suitable recesses and threaded holes for mounting the inserts 9 therein by means of bolts 10.

, 'A shaft 11 of the processing roll 2 is supported by a pad 12.

The window wall of the roll housing 5 is the bud 1 of the processing roll 2.
The wedge 13 is designed to have an interior which cooperates with the wedge 2.

In the guidance of the housing 5 by means of the adjusting screw 14,
By moving the wedges 13, the gap between the axes 11 of the work rolls 2 can be adjusted during readjustment of the rolling mill to handle billets of different sizes.

The rotation of the processing roll 2 around the axis 11 of the processing roll 2 is
According to the invention, this is actively carried out in synchronization with the reciprocation of the roll housing 5 in the guides 4 of the rolling mill frames 2, 3.

For this purpose, each work roll 2 is rotatably connected by a rocker bar 15 (Figs. 3, 4 and 5) to a support member 16 common to all rocker bars 15,
is formed as a hollow cylindrical casing attached to the frame 3 on the side where the billet 1 emerges from the working roll 2 and supported on the same axis as the billet 1.

As shown in FIG. 5, each swing rod 15 has one end bifurcated, and holds the corresponding processing roll 2 at the pivot joint.

The other end of the swing rod 15 is rotatably connected to one end of an arm 17 attached to holes provided in both end surfaces of the support members 1 and 6.

The outer end surface of the support member 16 is connected to the support member 16 of the auxiliary device for the axial feed 9 and tilting sump of the billet 1 according to the invention.
A removable cover 1 adapted to be housed inside the
8.

A feed device 19 for adjusting the billet 1 in the axial direction is supported by the rolling mill frame 3 on the inlet side of the billet 10 with respect to the processing rolls 2.

The feeding device 19 may be of any suitable known design, for example similar to a forging manipulator (detailed description of which will be omitted), and is used to grip the billet 1 at one end and to move the roll housing back and forth. Used to synchronously feed and tilt the billet axially.

Both end walls of the support member 16 are formed with a hole coaxial with the billet 1, which hole receives a guide member 20 in the form of a tube for the passage of the billet 1 to be processed.

The guide member 20 is supported on the support member 16 in order to move axially with the billet 1 and rotate about the axis.

For this purpose, the guide member 20 is supported in a bearing 21 fitted in a bore in the support member 16, the axial adjustment and rotation of which is effected by an auxiliary device for feeding and tilting the billet 1 axially. and its function is synchronized with the reciprocation of the rollback lamp.

The auxiliary device includes a clamp 22 for clamping the billet 1 on the guide member 20 supported in the opening of the support member 16, and a roll roll for displacing the guide member 20 in the axial direction. ... an air cylinder device 24 (having a link device 23 transmission-connected to the clamp 5 and a cylinder rotatably connected to the cylindrical portion of the support member 16);
(Fig. 6), and the piston rod 25 is connected to the ring 2.
It is rotatably connected to the guide member 20 by 0a, so that the guide member 20 is rotated.

By introducing pressurized air to one side of the piston in the cylinder of the air cylinder device 24, the piston rod 25 in the cylinder is forced out of the cylinder, thereby making it possible to rotate or tilt the guide member.

The clamp 22 consists of two jaws 26 (FIGS. 4 and 5) supported on opposite sides of the billet 1 to be processed in coaxial guides provided in the opening of the guide member 20.

Joe 26 on the other hand. It is fixed to the piston rod 27 of another air cylinder device 28 supported on the outside of the guide member 20, the other jaw 26 of which clamps when the clamp 22 is readjusted for a different outlet cross-section of the billet 1. 2
In order to adjust the gap between the jaws 26 of the guide member 2
It is firmly connected to an adjustment screw 29 provided in the screw hole 0.

The link device 23 is connected to the swing arm 30 (Figs. 3 and 4).
One end is rotatably connected to a ring 31 supported on the outer end of the guide member 20 between the two collars, and the other end is rotatably connected to the rolling mill frame 3.

The slider 33 is rotatably connected to one end of a double arm lever 35 having a rotation shaft attached to the frame 3, and the other end of the lever is rotatably connected to the roll housing 5 via a pull rod 36. freely connected.

Axial displacement of guide member 20 (billet 1 is fed)
is adjusted by a movable stop 37 cooperating with a ring 31 supported at one end of the guide member 20.

The rolling mill according to the invention operates as follows.

When the electric motor 6 (FIG. 4) is energized, its output shaft is rotated to reciprocate the roll housing 5 in the guide 4 of the rolling mill frame 3 via the gear transmission 8 and the cranking device 7.

At the same time, the processing roll 2 swings around the shaft 11 under the action of the swing rod 15.

The billet 1 to be processed is advanced to the processing rolls 2 by a feeding device 19 and is intermittently reduced by the processing rolls.

The reduction of the billet 1 with the working rolls 2 takes place as follows (reference is made to the stepwise rolling of a billet 1 with an octagonal cross-section chosen as an example).

Roll in the right direction indicated by the arrow in Figure 1...
During the actuation movement of the clamp 5, the axes O and 0' of the work rolls 2 (as shown in FIG. ) is advanced from position 01 to position 02 and from position 00' to position 0□', so that the work roll 2 is moved clockwise and counterclockwise around its axes O and O'. (shown as a solid line).

At this time, the curved part AB of the processing surface of the processing roll 2 contacts the billet 1 during the rotation of the processing roll and processes all four surfaces of the billet 10 simultaneously into a deformed cone, that is, the entire circumference of the cross section of the billet is processed. Processing is approximately uniform, the deformation zones formed by all the work rolls 2 are located within the length m of one deformation zone during the entire reduction period, and the deformation zones are relative to each other in the axial direction along the billet 1. without displacement,
Simultaneously move up into the deformation cone.

The advantages of the rolling method according to the invention have already been mentioned.

At the end of the operating position of each work roll 2 (indicated by a thin line in FIG. , the billet 1 is sized.

Reverse movement of the roll housing and reverse rotation of the processing roll (
The return stroke) is carried out in the direction of the arrow indicated by the dotted line in FIG.

At the end of the idle stroke, the billet 1 is rotated again around its axis by half α, or 45°, and at the same time is fed one step S in the direction of the pass line in the baseline direction.

This is done as follows.

The billet 1 is the jaw 2 of the clamp 22 in the guide member 20.
6, the end portion of the billet 1 is transferred to the feeding device 1
9 is released and the billet axial feeding and tilting auxiliary device supported on the side from which the billet emerges from the work roll 2 begins to operate.

During the rightward actuation movement of the roll housing (as shown in FIG. 4), the upper jaw 26 of the clamp 22 is in its uppermost position.

This is because no pressure is then applied to the piston of the air cylinder device 28.

Thus, the tip of the billet 1 passes freely between the jaws 26, which themselves are guided by the guide member 20 by the action of the linkage 23, which includes the arms 30, 32, 35° 36.
move to the left with.

When the working movement of the roll housing and the work roll is completed, the next part of the billet 1 has been sized, and the roll housing begins its return movement, the air cylinder device 28 of the clamp 22 moves the upper jaw 26 of the billet 1. press against the surface.

The guide member 20 therefore begins to move to the right and the working roll 2 begins to move away from the deformation cone K of the billet 1 during the return movement of the roll housing.

At the beginning of the return movement of the roll housing, billet 1
The guide member 20 is tightened in the nip of the processing roll 2.
cannot move to the right.

At that stage, the swinging of the arm 32 is caused by the slider 33
to compress the spring 34.

When the work roll 2 is returned away from the billet 1 at the end of its working movement, the spring 34 acts to accelerate the swinging of the arm 30 and the movement of the guide member 20 to the right, thereby causing the clamp 22 This facilitates a more rapid completion of the rightward feeding of the billet 1 clamped in the jaws 26 of.

When the billet 1 enters the shrinking process again, the jaws 26 are separated.

At the beginning of each working movement of the roll housing, pressure is applied to the piston of the air cylinder device 24 in order to tilt the billet 1.

When the work roll 2 is returned from the billet 1, the billet is rotated together with the guide member 20, this rotation ending when the work roll 2 is wide apart at the end of the return movement of the roll housing.

During the next return movement of the roll housing, the direction of inclination of the billet 1 is positively changed, thus preventing the billet 1 from twisting.

The length of the axial cross section S of the billet 1 up to the processing roll 2 is determined by the through stopper 3 which limits the swing angle of the arm 30 to the right.
Adjusted by 7.

The rolling mill according to the invention is simple in construction, reliable in operation and easily useful for carrying out the rolling method according to the invention.

Reliability of operation is a hallmark of the rocker rod 15, which provides active rotation of the work roll 2 synchronously with the actuation of the roll backcrank and the crank drive of the roll housing.

Other embodiments of the rolling mill drive can be used, in which case the reciprocation of the roll housing can be performed by simpler devices, such as hydraulic cylinders and linear prime movers that do not require reduction gears.

In the rolling mill according to the invention, the pressure of the billet 1 applied to the working roll 2 is not directly transmitted to the rolling mill parts, but is distributed over the rocking rod 15 and the axis 11vC of the driven roll 2.

The structure of the auxiliary device for axially feeding and tilting the billet 1 allows a portion of the billet to pass through the guide member 20 during the reduction process guided by the processing roll 2 and allows the idle movement of the processing roll 2. At the end of the process, the billet is allowed to move during the axial feeding step S.

Said auxiliary device makes a force-transmitting connection with the roll crank 5 to ensure their synchronous operation.

The use of a clamp 22 with a pneumatic drive to clamp the billet 1 ensures a smooth application of the force at the moment of clamping and during the tilting of the billet 1.

It should be understood that various variations in the structure of the rolling mill can be made by those skilled in the art, and that the structure of the rolling mill has been described as a non-limiting example.

The rolling of billets of low ductility alloys carried out according to the invention on a rolling mill implementing the method according to the invention confirms the above-mentioned advantages of the method and rolling mill of the invention and shows that it can be used commercially. .

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the metal billet rolling method in a single pass according to the present invention, and FIG.
- Fig. 3 is a longitudinal sectional view of a rolling mill for carrying out the rolling method according to the present invention; Fig. 4 shows a chain mechanism of the rolling mill; FIG. 5 is a cross-sectional view taken along plane V-7 of FIG. 3 with an axial section of a portion of one processing roll, and FIG.
FIG. 1: Billet to be processed, 2: Processing roll, 5: Roll housing, 9: Processing roll insert), 10: Bolt, 11: Processing roll shaft, 15: Swing rod, 16: Support member, 20: Guide Member, 22: Clamp, 23: Link device, 24: Air cylinder device, 25: Piston rod, 2
6: clamp jaw, 27: piston rod, 28: air cylinder device, 29: adjustment screw, m: length of deformation area 5
α: Angle, o, o': Geometric axis of rotation of the processing roll, e: Eccentricity, AB: Curved part of the processing roll surface, ρ: Radius of curvature, BC: Sized section, t: Sized section Length, S: Billet axial feeding process, λ: Billet elongation rate.

Claims (1)

[Claims] 1. A metal billet is reduced by processing rolls, and during processing, the billet is reduced almost uniformly over its entire circumference, and the deformation area induced by all processing rolls is reduced to one limited throughout the reduction period within the length of the deformation zone formed by the work rolls and significantly longer than the length of the deformation zone formed into the billet by each work roll at each given moment. In a method of stepwise rolling of a metal billet, in which a transition section is formed in the billet as a deformed cone having a length along the axis, and the axial feed and the reduction process are alternately carried out during one rolling stroke, each reduction During the deformation process of the billet 1 over its entire length before machining, the billet forms an angle between one plane perpendicular to the axis 0 of one work roll 2 and another plane perpendicular to the axis of the adjacent work roll. A method for stepwise rolling of a metal billet, characterized in that the sizing of the billet is tilted alternately in opposite directions over half of α, and the sizing of the billet is started at the end of the reduction period and ends simultaneously with the completion of the reduction of the transition section. . 2 a frame having a roll housing running parallel to the axis of the billet to be processed and supported on a guide member; said housing being transmission connected to a drive of the rolling mill for reciprocating on said guide member during rolling; , and supporting a variable radius machining roll arranged symmetrically with respect to the axis of the billet; a feeding device for feeding the billet in the axial direction; in a metal billet rolling mill, comprising: being supported by the frame on the side into which the billet enters and being transmission connected to the rolling mill drive; Metal billet rolling mill, characterized in that the geometrical axis of rotation 0, 0' of said working roll is located in a plane perpendicular to the axis of said billet 1. . 3. In the metal billet rolling mill according to claim 2, each work roll 2 is formed into a fan shape in a plane perpendicular to its geometric axis of rotation, and the axis of this fan shape is
It is arranged at an eccentricity e with respect to the geometric rotational axis of the processing roll 2, and forms a curved portion AB having a variable radius of curvature ρ on its surface, and a curved portion AB is formed on the side where the billet 1 comes out from the processing roll 2. A sizing section BC that matches section AB is provided, and all generatrices on the surface of the sizing section are aligned with processing roll 2.
At the end of the machining movement, a fixed size section B in the longitudinal direction of the billet 1 is formed so as to pass parallel to the axis of the billet 1.
The length t of C is determined by the formula t≧S, where S is the axial feed of the billet 1 in one stroke and λ is the elongation rate of the billet.
A metal billet rolling mill characterized in that λ is determined from λ. 4. In the metal billet rolling mill according to claim 3, the work roll portion having the curved portion AB and the fixed size portion BC is formed of a removable insert 9 made of a wear-resistant and fire-resistant alloy, and the other portions of the work roll are , a metal billet rolling mill characterized in that it has a suitable recess and a threaded hole therein for mounting an insert 9 by means of a bolt 10. 5. In the metal billet rolling mill according to claim 2, a supporting member 16 is fixed to the frame 3 of the rolling mill, and a large number of rocking rods 15 are rotatably connected to this supporting member, and processing is performed. The active rotation of each work roll 2 around the circumference 9 of the roll axis 11 is achieved by one end rotatably connected to the work roll 2 and to a support member 16 common to all rocking rods 15. A metal billet rolling mill, characterized in that the rolling is carried out by means of a rocking rod 15 which has its other end attached to a frame 3 on the side where the billet 1 emerges from the working rolls 2. 6. In the metal billet rolling machine according to claim 5, each swing rod 15 has one end that is bifurcated so as to accommodate the corresponding processing roll 2 at the position of the pivot joint. A metal billet rolling machine characterized by: 7. In the metal billet rolling mill according to claim 5, the support member 16 is formed of a hollow cylindrical casing supported on the same axis as the billet 1, and the casing is supported on the same axis as the billet 1. The guide member 20 is formed as a tube for passage of the billet 1 and is used to feed the billet in the axial direction in the support member 16 and to receive the guide member 20. It is rotatable about the axis together with the billet 1 and movable in the axial direction by means of an auxiliary device of the tilting holder, and has a clamp 22 supported in the opening of the guide member 20 for clamping the billet to the guide member 20. Furthermore, a link device 23 transmission-connecting the outlet end of the guide member 20 to the roll clamp 5 to cause the guide member 20 to move in the axial direction; A metal billet rolling mill comprising an air cylinder device 24 having a piston rod 25 freely connected and a cylinder rotatably connected to a support member 16. 8. In the metal billet rolling machine as set forth in claim 7, the clamp 22 is linearly attached to one of the two jaws 26 supported on both sides of the billet 10 in the coaxial guide provided in the opening of the guide member 20. Joe 26 is
It is fixed to the piston rod 27 of another air cylinder device 28 supported outwardly on the guide member 20, the other jaw 26 being connected to an adjusting screw 29 for adjusting the gap between the two jaws 26. A metal billet rolling machine characterized by: