CN217173879U

CN217173879U - Fixed pickling cleaning tank

Info

Publication number: CN217173879U
Application number: CN202220177962.4U
Authority: CN
Inventors: 王建旭; 乔前宝; 计艳利
Original assignee: Leting Qianjin Steel Structure Co ltd
Current assignee: Leting Qianjin Steel Structure Co ltd
Priority date: 2022-01-24
Filing date: 2022-01-24
Publication date: 2022-08-12
Anticipated expiration: 2032-01-24

Abstract

The application relates to a fixed pickling washing tank belongs to the technical field of pickling equipment, and it includes the cell body, swing joint has the filter screen in the cell body, be equipped with the runner assembly that is used for driving the filter screen upset between filter screen one end and the cell body, just the filter screen is kept away from one side of runner assembly is equipped with and is used for the upset the auxiliary assembly of filter screen. This application has reinforcing finished piece pickling effect, improves the effect of finished piece quality.

Description

Fixed pickling cleaning tank

Technical Field

The application relates to the technical field of pickling equipment, in particular to a fixed pickling tank.

Background

Acid pickling is one of the pretreatment or intermediate treatment steps of electroplating, enameling, rolling and other processes, and generally, a workpiece is put into an acid solution such as sulfuric acid to remove oxide scales and rusts on the surface of the workpiece such as a steel workpiece and the like, so as to clean the metal surface.

Chinese patent with publication number CN203200343U discloses a pickling tank, including cell body and capping, the cell body includes the acidproof glass steel layer of inside lining, interbedded ceramic fibre layer and outer first steel deck, and first steel deck surface has first acidproof resin layer, and the capping corresponds the cell body setting, and the capping includes the second acidproof resin layer on second steel deck and second steel deck surface, has thermal insulation performance, increase of service life.

Acid liquor produces acid sludge when pickling the finished piece, and the descaling bath among the relevant art does not clear up the acid sludge, easily causes the acid sludge to adhere to the finished piece surface from this, and the condition that influences the finished piece pickling effect takes place, and then influences the finished piece quality.

SUMMERY OF THE UTILITY MODEL

In order to strengthen finished piece pickling effect, improve the finished piece quality, this application provides a fixed pickling tank.

The application provides a fixed pickling washing tank adopts following technical scheme:

the utility model provides a fixed pickling washing tank, includes the cell body, swing joint has the filter screen in the cell body, be equipped with the runner assembly that is used for driving the filter screen upset between filter screen one end and the cell body, just the filter screen is kept away from one side of runner assembly is equipped with and is used for the upset the auxiliary assembly of filter screen.

Through adopting above-mentioned technical scheme, fixed pickling washing tank accomplishes the pickling back, and drive runner assembly and auxiliary assembly overturn the filter screen, and the acid sludge that forms in the acid liquor is filtered to the filter screen this moment, and the acid sludge removes to filter screen one side gradually along with the filter screen upset simultaneously, is convenient for collect the acid sludge, avoids the condition that the finished piece is stained with the acid sludge in the acid liquor at the in-process of pickling to take place as far as possible to reinforcing finished piece pickling effect improves the finished piece quality.

Optionally, the rotating assembly comprises a driven wheel fixedly connected with one end of the filter screen, the groove body is fixedly connected with a driving wheel meshed with the driven wheel, and the axis of the driving wheel is fixedly connected with a rotating motor.

Through adopting above-mentioned technical scheme, when clearing up fixed pickling washing tank, the rotation motor drive action wheel rotates to drive and take place to rotate from the driving wheel, and then overturn to the filter screen, realize filtering out the dregs of acid in the acidizing fluid at the in-process of upset, and make the dregs of acid remove to filter screen one side gradually at the rotation in-process of filter screen, thereby the dregs of acid in the clearance cell body, the condition emergence of avoiding the finished piece to be stained with the dregs of acid in the acidizing fluid at the in-process of pickling as far as possible, thereby reinforcing finished piece pickling effect.

Optionally, the auxiliary assembly is including rotating the connection and being in the cell body both sides are located the outside auxiliary rod of cell body, the auxiliary rod sets up the filter screen is kept away from the one end from the driving wheel, the filter screen is close to the both sides of auxiliary rod one end all are equipped with the connecting rod, the connecting rod overlap joint is in on the cell body, just the connecting rod is kept away from the one end of filter screen all is located the cell body outside, just the auxiliary rod is kept away from the one end of cell body with one side the connecting rod overlap joint, just connecting rod one side is equipped with and is used for driving auxiliary rod pivoted driving motor.

Through adopting above-mentioned technical scheme, in-process that overturns the filter screen, the auxiliary rod of driving motor drive cell body both sides rotates, the auxiliary rod upwards perks the connecting rod at the pivoted in-process this moment, thereby turn over the filter screen in the one side of keeping away from runner assembly, thereby it is more convenient to make runner assembly turn over a filter screen, thereby can further realize filtering out the acid sludge in the acidizing fluid at the in-process of upset, thereby clear up the acid sludge in the cell body, avoid the condition emergence that the finished piece is stained with the acid sludge in the acidizing fluid at the in-process of pickling as far as possible, thereby reinforcing finished piece pickling effect.

Optionally, the cell body is close to the lower extreme from driving wheel one side installs out the acid pipe, go out the acid pipe with the inside intercommunication of cell body, just it keeps away from to go out the acid pipe the acid-resistant valve is installed to the one end of cell body, just it installs the filter that the slope set up to go out the acid intraductal, the filter is to being close to the one side tilt up of cell body.

Through adopting above-mentioned technical scheme, when the filter screen filters the dregs of acid in the acidizing fluid, open the acid-resistant valve, the spent acid can be followed and a tub department is discharged, and the filter can carry out secondary filter to tiny dregs of acid in the spent acid to it takes place to reduce the circumstances that the dregs of acid blockked up the acid-resistant valve, thereby avoids as far as possible causing the circumstances of damage to take place because of the long-term use of acid-resistant valve, and then prolongs the life of acid-resistant valve, further strengthens finished piece pickling effect, improves the finished piece quality.

Optionally, a slag storage barrel is fixedly connected to the lower side of the acid outlet pipe, the slag storage barrel is communicated with the acid outlet pipe, the slag storage barrel is located on one side, close to the groove body, of the filter plate, a mounting cover is arranged at one end, far away from the acid outlet pipe, of the slag storage barrel, and the mounting cover is in threaded connection with the slag storage barrel.

Through adopting above-mentioned technical scheme, when the filter filters the tiny dregs of acid in the spent acid, the dregs of acid gets into under the guide effect of filter and stores up a sediment section of thick bamboo, reduce the dregs of acid and in the accumulational possibility in filter one side to guarantee the work efficiency of filter, can collect and clear up the dregs of acid that filters out simultaneously, further reduce the dregs of acid and block up the condition emergence of acidproof valve, and then the life of prolonging acidproof valve, thereby can strengthen finished piece pickling effect, improve the finished piece quality.

Optionally, one side of the slag storage barrel, which is far away from the tank body, is set to be an inclined plane, the inclined plane is close to one side, which is far away from the filter screen, of the open end of the tank body, the inclined plane is gradually inclined upwards, and an acid inlet is formed above the open end of the tank body.

Through adopting above-mentioned technical scheme, new acidizing fluid can follow into in the acid mouth gets into the cell body, and new acidizing fluid flows into the cell body along the cell body inclined plane of entering acid mouth below to avoid new acidizing fluid to take place because of the condition that the velocity of flow is too fast causes splashing in the process of adding as far as possible, thereby reduce new acidizing fluid extravagant, reach reinforcing finished piece pickling effect, improve the effect of finished piece quality.

Optionally, the upper end of one side of the tank body close to the acid inlet is fixedly connected with a connecting plate, and the filter screen is close to one side of the connecting plate and a mounting assembly for connecting the connecting plate and the connecting plate is arranged between the filter screen and the connecting plate.

Through adopting above-mentioned technical scheme, when the filter screen accomplished the filtration of acid sludge and when the horizontal position was got back to in the upset, the installation component was connected filter screen and connecting plate, kept the relative stability of filter screen and cell body, made the filter screen be difficult for taking place relative movement under the effect of external force to avoid the filter screen to take place to remove the back acid sludge as far as possible and be stained with the condition emergence of attaching at the cell body inner wall, thereby reinforcing finished piece pickling effect improves the finished piece quality.

Optionally, the installation component is including setting up the filter screen is kept away from the installation piece of follow driving wheel one end, set up on the filter screen with the holding tank that the installation piece suited, installation piece one end insert in the holding tank and with holding tank sliding connection, fixedly connected with spring in the holding tank, spring one end with installation piece fixed connection, just the filter screen passes through the installation piece with the connecting plate is pegged graft, the terminal surface that the installation piece inserted connecting plate one end sets up to the arc.

By adopting the technical scheme, when the filter screen finishes cleaning acid sludge and turns back into the tank body, the mounting block is firstly contacted with the side wall of the connecting plate, the side wall of the connecting plate moves the mounting block to the direction close to the accommodating tank, the spring is compressed at the moment, and when the filter screen rotates to the horizontal position, the spring moves the mounting block to the direction close to the connecting plate until the mounting block is inserted into the connecting plate; when the filter screen rotated once more, the connecting plate extrudees the installation piece once more, breaks away from the connecting plate until will installing the piece, and the filter screen breaks away from the connecting plate this moment to make the installation component can realize the locking of filter screen and cell body and break away from under the environment that does not need the manual work, improve work efficiency, reduce personnel's consumption simultaneously.

In summary, the present application includes at least one of the following beneficial technical effects:

1. after the fixed pickling tank finishes pickling, the rotating assembly and the auxiliary assembly are driven to overturn the filter screen, the filter screen filters acid residues formed in the acid liquor, and the acid residues move to one side of the filter screen gradually along with the overturning of the filter screen, so that the acid residues are convenient to collect, the condition that the workpieces are adhered with the acid residues in the acid liquor in the pickling process is avoided as much as possible, the pickling effect of the workpieces is enhanced, and the quality of the workpieces is improved;

2. in the process of overturning the filter screen, the driving motor drives the auxiliary rods on the two sides of the tank body to rotate, and at the moment, the auxiliary rods upwards tilt the connecting rods in the rotating process, so that the filter screen is turned over on one side far away from the rotating assembly, and the rotating assembly can turn over the filter screen more conveniently, so that acid sludge in acid liquor can be further filtered out in the overturning process, the acid sludge in the tank body is cleaned, the condition that a workpiece is stained with the acid sludge in the acid liquor in the pickling process is avoided as much as possible, and the pickling effect of the workpiece is enhanced;

3. when the horizontal position was got back to in the filtration and the upset of acid sludge was accomplished to the filter screen, the installation component was connected filter screen and connecting plate, kept the relative stability of filter screen and cell body, made the filter screen be difficult for taking place relative movement under the effect of external force to avoid the filter screen to take place to remove the back acid sludge and be stained with the condition emergence of attaching at the cell body inner wall as far as possible, thereby reinforcing finished piece pickling effect improves the finished piece quality.

Drawings

FIG. 1 is a schematic view of the overall structure of a stationary pickling bath according to an embodiment of the present invention.

Fig. 2 is a schematic view showing the overall structure of the rotating assembly and the auxiliary assembly in the embodiment of the present application.

FIG. 3 is a schematic structural diagram of a slag storage barrel and a mounting cover in the embodiment of the application.

Fig. 4 is a schematic structural diagram of a mounting assembly in an embodiment of the present application.

Description of reference numerals: 1. a trough body; 11. a connecting plate; 111. a through hole; 112. mounting grooves; 2. a filter screen; 21. a connecting rod; 22. accommodating grooves; 3. an acid inlet; 4. an acid outlet pipe; 41. an acid-resistant valve; 42. a filter plate; 43. a slag storage cylinder; 431. installing a cover; 44. a baffle plate; 5. a rotating assembly; 51. a driven wheel; 52. a driving wheel; 53. rotating the motor; 6. an auxiliary component; 61. an auxiliary lever; 62. a connecting shaft; 63. a drive motor; 7. a collecting hopper; 8. mounting the component; 81. mounting blocks; 82. a spring.

Detailed Description

The present application is described in further detail below with reference to the accompanying drawings.

The embodiment of the application discloses a fixed pickling tank. Referring to fig. 1 and 2, the fixed pickling tank includes a tank body 1, a filter screen 2 for filtering acid residues in acid liquor is arranged in the tank body 1, an acid inlet 3 is arranged above one side of the tank body 1, and one side of the tank body 1 close to the acid inlet 3 is arranged to be an inclined plane gradually inclined upwards to one side far away from the filter screen 2. An acid outlet pipe 4 is arranged at the lower end of one side of the outer part of the tank body 1 far away from the acid inlet 3, the acid outlet pipe 4 is communicated with the inner part of the tank body 1, and an acid-proof valve 41 is arranged at one side of the acid outlet pipe 4 far away from the tank body 1.

During cleaning, the acid-proof valve 41 is opened, waste acid is discharged from the acid outlet pipe 4, acid sludge in the waste acid is filtered and is left in the filter screen 2 for collection, after the waste acid is completely discharged, acid is added into the tank body 1 through the acid inlet 3, and at the moment, new acid liquid flows into the tank body 1 along the inclined plane, so that cleaning of the fixed acid cleaning tank is completed, and splashing of the acid liquid is reduced.

Referring to fig. 2 and 3, in order to clean the acid sludge conveniently, both ends of one side of the filter screen 2 close to the bottom of the tank body 1 are set to be fillets, a rotating assembly 5 used for driving the filter screen 2 to rotate is arranged between one end of the filter screen 2 far away from the feed inlet and the tank body 1, and an auxiliary assembly 6 used for driving the filter screen 2 to rotate is arranged at one end of the tank body 1, which is close to the feed inlet. The outside fixedly connected with of one side that cell body 1 is close to runner assembly 5 collects and fights 7, and the lateral wall height that collects fight 7 and keep away from cell body 1 one side is higher than cell body 1 height.

After fixed pickling tank accomplished the pickling, drive runner assembly 5 and auxiliary assembly 6 overturn filter screen 2, and the dregs of acid that forms in the acidizing fluid of filter screen 2 this moment filters, and the dregs of acid moves to filter screen 2 one side gradually along with the upset of filter screen 2 simultaneously, and when filter screen 2 rotated to and fights 7 one side butt of keeping away from cell body 1 with the collection, the dregs of acid in the filter screen 2 got into during the collection was fought 7, accomplished the clearance.

The rotating assembly 5 comprises a driven wheel 51 fixedly connected to one end, close to the collecting hopper 7, of the filter screen 2, one end, close to the driven wheel 51, of the tank body 1 is arranged to be a round angle, one end, close to the driven wheel 51, of the tank body 1 is rotatably connected with a driving wheel 52 meshed with the driven wheel 51, and the axis of one side, away from the tank body 1, of the driving wheel 52 is fixedly connected with a rotating motor 53.

When the acid sludge in the acidizing fluid needs to be cleared up, rotate motor 53 drive action wheel 52 and rotate, the number of times drives filter screen 2 from driving wheel 51 and rotates, at this moment in filter screen 2's rotation in-process with acid sludge and acidizing fluid separation and stay in filter screen 2, and the acid sludge removes to the direction that is close to collection fill 7 gradually at filter screen 2's rotation in-process, when filter screen 2 rotates to the one side butt of keeping away from cell body 1 with collection fill 7, the acid sludge in the filter screen 2 gets into under the slight striking of collection fill 7 walls and filter screen 2 and collects in fighting 7, thereby the completion is to the clearance of fixed pickling washing tank.

The auxiliary assembly 6 comprises two auxiliary rods 61 arranged at the end, close to the acid inlet 3, of the tank body 1, the two auxiliary rods 61 are arranged at two sides of the outside of the tank body 1, the tank body 1 is internally provided with a connecting shaft 62 in a penetrating and rotating mode, and the auxiliary rods 61 are arranged at two ends of the connecting shaft 62 and fixedly connected with the connecting shaft 62. The equal fixedly connected with connecting rod 21 that a perpendicular to filter screen 2 set up in both sides that filter screen 2 is close to into sour mouth 3 one end, auxiliary rod 61 be located with auxiliary rod 61 with the connecting rod 21 below of one side and with connecting rod 21 overlap joint, and connecting axle 62 one side is installed and is used for driving auxiliary rod 61 pivoted driving motor 63.

When the rotating assembly 5 drives the filter screen 2 to rotate, the driving motor 63 drives the auxiliary rod 61 to rotate anticlockwise, so that the filter screen 2 is tilted from one end far away from the driven wheel 51, and the effect of assisting the rotating assembly 5 to rotate the filter screen 2 can be achieved.

Referring to fig. 3 and 4, a horizontally arranged connecting plate 11 is fixedly connected to the inside of the upper end of the tank body 1 near the acid inlet 3, and a through hole 111 matched with the acid inlet 3 is formed in the connecting plate 11, so that the filter screen 2 is stable when not required to be filtered, and a mounting assembly 8 for fixing the filter screen 2 is arranged between the connecting plate 11 and one side of the filter screen 2 near the connecting plate 11. The mounting assembly 8 comprises a mounting block 81 arranged at one end of the filter screen 2 close to the connecting plate 11, and the end face of one end of the mounting block 81 close to the connecting plate 11 is arc-shaped. One side of the filter screen 2 close to the mounting block 81 is provided with a receiving groove 22 adapted to the mounting block 81, one end of the mounting block 81 is inserted into the receiving groove 22 and is slidably connected with the receiving groove 22, a spring 82 is fixedly connected to the receiving groove 22, and one end of the spring 82 close to the mounting block 81 is fixedly connected with the mounting block 81. One end of the connecting plate 11 close to the mounting block 81 is provided with a mounting groove 112 corresponding to the mounting block 81, and the filter screen 2 is connected with the connecting plate 11 by the way of splicing the mounting block 81 with the mounting groove 112.

When the filter screen 2 finishes cleaning acid sludge and turns back to the tank body 1, the mounting block 81 is firstly contacted with the side wall of the connecting plate 11, the side wall of the connecting plate 11 moves the mounting block 81 to the direction close to the accommodating groove 22, the spring 82 is compressed at the moment, and when the filter screen 2 rotates to the horizontal position, the spring 82 moves the mounting block 81 to the direction close to the connecting plate 11 until the mounting block 81 is inserted into the connecting plate 11; when the filter screen 2 rotates again, the connecting plate 11 presses the mounting block 81 again until the mounting block 81 is separated from the connecting plate 11, at which time the filter screen 2 is separated from the connecting plate 11, and the filter screen 2 can continue to rotate.

Referring to fig. 2 and 3, in order to completely clean acid residues in waste acid, a filter plate 42 which is inclined upwards in the direction close to the tank body 1 is fixedly connected in the acid outlet, and the filter plate 42 is positioned on one side of the acid-proof valve 41 close to the tank body 1. One side fixedly connected with that goes out acid outlet and follow driving wheel 51 and store up a sediment section of thick bamboo 43 with acid outlet intercommunication, the one end that stores up a sediment section of thick bamboo 43 and be close to acid outlet pipe 4 is equipped with the baffle 44 that the slope set up, and baffle 44 is located acid outlet pipe 4 and baffle 44 one end and the fixed connection of 4 inner walls of acid outlet pipe, and the other end is to the one side tilt up that is close to filter 42. The slag storage barrel 43 is positioned on one side of the filter plate 42 close to the tank body 1, an installation cover 431 is arranged at one end, away from the acid outlet pipe 4, of the slag storage barrel 43, and the installation cover 431 is in threaded connection with the slag storage barrel 43.

When the waste acid in the tank body 1 is discharged, the acid-proof valve 41 is opened, the waste acid enters the acid outlet pipe 4, the filter plate 42 separates the fine acid sludge from the waste acid, the acid sludge is guided, the acid sludge enters the slag storage cylinder 43, the baffle 44 on the slag storage cylinder 43 avoids the acid sludge from separating from the slag storage tank under the flowing of the acid liquid as much as possible, after the acid is discharged, the mounting cover 431 is twisted to separate the mounting cover 431 from the slag storage cylinder 43, the acid sludge in the slag storage cylinder 43 is poured out, and the acid sludge cleaning is completed.

The implementation principle of the fixed pickling tank in the embodiment of the application is as follows: after fixed pickling tank accomplished the pickling, action wheel 52 and from the rotation of driving wheel 51 drive filter screen 2, auxiliary rod 61 drives the upset of filter screen 2 at the other end simultaneously, filter screen 2 filters the dregs of acid that forms in the acidizing fluid this moment, the dregs of acid move to filter screen 2 one side along with the upset of filter screen 2 gradually simultaneously, when filter screen 2 rotates to one side butt far away from cell body 1 with collection fill 7, the dregs of acid in the filter screen 2 gets into collection fill 7, tiny dregs of acid in the spent acid gets into out acid pipe 4 along with the spent acid, filter 42 separates tiny dregs of acid and spent acid, and lead to the dregs of acid, make the dregs of acid get into storage sediment section of thick bamboo 43, after the row of sour is accomplished, twist installation lid 431 and make installation lid 431 break away from with storage sediment section of thick bamboo 43, and pour out the dregs of acid in the storage sediment section of thick bamboo 43, accomplish the dregs of acid clearance.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims

1. A fixed pickling cleaning tank comprises a tank body (1), and is characterized in that: swing joint has filter screen (2) in cell body (1), be equipped with runner assembly (5) that are used for driving filter screen (2) upset between filter screen (2) one end and cell body (1), just filter screen (2) are kept away from one side of runner assembly (5) is equipped with and is used for the upset auxiliary assembly (6) of filter screen (2).

2. The stationary acid wash tank of claim 1, wherein: the rotating assembly (5) comprises a driven wheel (51) fixedly connected with one end of the filter screen (2), the groove body (1) is fixedly connected with a driving wheel (52) meshed with the driven wheel (51), and a rotating motor (53) is fixedly connected with the axis of the driving wheel (52).

3. The stationary acid wash tank of claim 2, wherein: auxiliary assembly (6) are connected including rotating cell body (1) both sides are located cell body (1) outside auxiliary rod (61), auxiliary rod (61) set up filter screen (2) are kept away from the one end of following driving wheel (51), filter screen (2) are close to the both sides of auxiliary rod (61) one end all are equipped with connecting rod (21), connecting rod (21) overlap joint is in on cell body (1), just connecting rod (21) are kept away from the one end of filter screen (2) all is located the cell body (1) outside, just auxiliary rod (61) are kept away from the one end of cell body (1) with same one side connecting rod (21) overlap joint, just connecting rod (21) one side is equipped with and is used for driving auxiliary rod (61) pivoted driving motor (63).

4. The stationary acid wash tank of claim 2, wherein: cell body (1) is close to go out sour pipe (4) are installed to the lower extreme from driving wheel (51) one side, go out sour pipe (4) with the inside intercommunication of cell body (1), just it keeps away from to go out sour pipe (4) acid-proof valve (41) are installed to the one end of cell body (1), just install filter (42) that the slope set up in going out sour pipe (4), filter (42) are to being close to one side tilt up of cell body (1).

5. The stationary acid wash tank of claim 4, wherein: go out sour pipe (4) downside fixedly connected with and store up a sediment section of thick bamboo (43), store up a sediment section of thick bamboo (43) with go out sour pipe (4) intercommunication, just store up a sediment section of thick bamboo (43) and be located filter (42) are close to one side of cell body (1), just store up a sediment section of thick bamboo (43) and keep away from the one end of going out sour pipe (4) is equipped with installation lid (431), installation lid (431) with store up a sediment section of thick bamboo (43) threaded connection.

6. The stationary acid wash tank of claim 5, wherein: one side of the slag storage barrel (43) is arranged to be an inclined plane, the inclined plane is close to one end, with an opening, of the tank body (1) is gradually inclined upwards to one side far away from the filter screen (2), and the inclined plane is close to an acid inlet (3) is formed above one end, with an opening, of the tank body (1).

7. The stationary acid wash tank of claim 6, wherein: the tank body (1) is close to one side upper end fixedly connected with connecting plate (11) of acid inlet (3), just filter screen (2) are close to one side of connecting plate (11) with be equipped with between connecting plate (11) and connect installation component (8) between them.

8. The stationary acid wash tank of claim 7, wherein: installation component (8) are including setting up filter screen (2) are kept away from installation piece (81) from driving wheel (51) one end, set up on filter screen (2) with installation piece (81) holding tank (22) that suit, installation piece (81) one end is inserted in holding tank (22) and with holding tank (22) sliding connection, fixedly connected with spring (82) in holding tank (22), spring (82) one end with installation piece (81) fixed connection, just filter screen (2) are passed through installation piece (81) with connecting plate (11) are pegged graft, the terminal surface that installation piece (81) inserted connecting plate (11) one end sets up to the arc.