CN217236545U

CN217236545U - Efficient cooling slewer

Info

Publication number: CN217236545U
Application number: CN202221173621.6U
Authority: CN
Inventors: 周远莉; 任强; 全健森; 金玲玲
Original assignee: Keda Clean Energy Co Ltd
Current assignee: Keda Clean Energy Co Ltd
Priority date: 2022-05-16
Filing date: 2022-05-16
Publication date: 2022-08-19
Anticipated expiration: 2032-05-16

Abstract

The utility model discloses an efficient cooling slewer belongs to chemical industry technical field. The utility model discloses a rotary kiln main part, first header tank, second header tank and heat exchange tube, wherein, first header tank and second header tank process into annular structure, install respectively in rotary kiln main part both ends, and the heat exchange tube is wholly installed in the interior intracavity of rotary kiln main part, and the heat exchange tube both ends communicate with the header tank that both sides set up, through combining heat exchange tube and rotary kiln main part ingeniously, can effectively improve cooling efficiency, promote the cooling effect; meanwhile, a water-cooling jacket is formed between the inner cylinder and the outer cylinder of the rotary kiln main body and communicated with the water collecting tank, and materials are in direct contact with the wall surface of the inner cylinder during cooling, so that the heat exchange area is greatly increased, and the heat exchange efficiency is improved. The utility model discloses a device cooling efficiency is high, simple structure, and it is convenient to make, can effectively practice thrift the cost for follow-up transport of material, storage, packing.

Description

Efficient cooling slewer

Technical Field

The utility model belongs to the technical field of the chemical industry, more specifically say, relate to an efficient cooling slewer for high temperature solid particle cools off after calcining raw materials, reduction reaction.

Background

The rotary kiln is a high-temperature material firing device, and after the material is sintered by the rotary kiln, the material temperature is high, the material needs to be rapidly cooled, and the qualification rate of products is ensured, so that a set of cooling system needs to be specially designed for the rotary kiln, and forced cooling is carried out on the rotary kiln. At present, the structural forms of the commonly used cooling rotary device are generally divided into a water immersion type and a spraying type. Wherein, the immersion structure is that partial kiln body is arranged in the water tank, which occupies large area and has poor cooling effect. The spraying type structure is simple, but the cooling water consumption is large, and the field use environment is severe.

Through retrieval, relevant patents have been published on cooling rotary devices, for example, chinese patent application nos.: 201921926856.6, filing date: 11 and 8 months in 2019, the name of the invention is: a rotary kiln spray type cooling system. The cooling system of the application comprises a main pipeline arranged below a rotary kiln body, a plurality of groups of spraying devices arranged above the rotary kiln body and arranged at intervals along the feeding direction of the rotary kiln body, and a water tank arranged below the discharge end of the rotary kiln body; an opening for cooling water to flow into the water tank is formed in the top of the water tank, and a water outlet of the water tank is communicated with a water inlet of the main pipeline; each group of spraying devices is communicated with the main pipeline through a communicating pipe; and a cooling device is arranged in the water tank.

This application improves through the fountain cooling system to conventional, has promoted the cooling effect to a certain extent and has reduced the waste of cooling water. But the application still adopts a spraying mode to cool the materials in the rotary kiln, and on one hand, the spraying cooling mode has limited cooling effect; on the other hand, the plurality of pipelines arranged outside the rotary kiln of the application still occupy a certain space, the occupied area is large, and the cooling effect can be better achieved only if the consumption of cooling water is still relatively large.

For another example, the chinese patent application number is: 201821833543.1, application date is: 11, 8 months and 2018, the name of the invention is: a cooling device of a rotary kiln. The device of the application comprises a base, a horizontal moving mechanism and an air cooling device, wherein the air cooling device is arranged on the base, and the horizontal moving mechanism drives the air cooling device to axially move along the rotary kiln; the air cooling device comprises an air outlet pipeline, a cooling air pipeline and an air supply device, the air outlet pipeline is located below the rotary kiln, the air outlet pipeline is close to one side of the rotary kiln, a plurality of air outlets are further uniformly formed in the side of the rotary kiln, the air outlet pipeline is further connected with the air supply device through the cooling air pipeline, and the air supply device is used for supplying cooling air.

The application adopts the forced air cooling to realize the cooling to the rotary kiln, and its effect is relatively poor compared with water-cooling, and also need set up corresponding device and mechanism around the rotary kiln, and area is big.

SUMMERY OF THE UTILITY MODEL

1. Problems to be solved

An object of the utility model is to overcome the above not enough of current cooling slewer existence, provide an efficient cooling slewer. The utility model discloses a combine heat exchanger structure and slewer ingenious, cooling efficiency is high, simple structure, and it is convenient to make, can effectively practice thrift the cost for follow-up transport of material, storage, packing.

2. Technical scheme

In order to solve the above problem, the utility model discloses the technical scheme who adopts as follows:

the utility model discloses an efficient cooling slewer, including the rotary kiln main part, still including installing first header tank, second header tank and the heat exchange tube in the rotary kiln main part, wherein, first header tank and second header tank processing are the loop configuration, install respectively in rotary kiln main part both ends, and heat exchange tube integral erection is in the internal intracavity of rotary kiln main part, and the header tank intercommunication that sets up in heat exchange tube both ends and both sides. The utility model discloses a with the ingenious combination of heat exchange tube and rotary kiln main part, can effectively improve cooling efficiency, promote the cooling effect, simultaneously, the utility model has the advantages of simple overall structure, need not to set up other equipment and device in the rotary kiln outside to effectively solved because of traditional slewer cooling arrangement is bulky and take up the big problem in space. More optimally, the utility model discloses a rotary kiln main part adopts the binocular structure of inside and outside barrel, and the clearance of leaving between the inside and outside barrel forms the water-cooling and presss from both sides the cover, and the water-cooling presss from both sides the cover and is linked together with the header tank, and the accessible lets in the cooling water to between this water-cooling presss from both sides the cover and the heat exchange tube, material and interior barrel wall direct contact, greatly increased heat transfer area, improved heat exchange efficiency.

As a further improvement, the first water collecting tank is arranged at the feed end of the rotary kiln body, and the second water collecting tank is arranged at the discharge end of the rotary kiln body. The rotary kiln discharge end department still installs water inlet assembly and water outlet assembly, wherein, water inlet assembly links to each other with the header tank on the one hand, on the other hand passes through the pipeline and the rotary joint links to each other with outside cooling water supply device, through water inlet assembly's setting, outside cooling water gets into the header tank through water inlet assembly, carry again in heat exchange tube and the water-cooling jacket, carry out the heat transfer to the high temperature material, and simultaneously, water outlet assembly and rotary joint intercommunication, this rotary joint also designs for the jacket formula structure, inside is used for into water, outside is used for out water, can be with the water after the heat transfer from the discharge in the rotary kiln main part.

As a further improvement, the water inlet component is communicated with the second water collecting tank, and the water outlet component is communicated with the water-cooling jacket of the rotary kiln main body. The cooling water can get into in the heat transfer pipe from the second header tank, then gets into the water-cooling jacket through first header tank to guarantee inside the rotary kiln, when the material contacted with the heat transfer pipe, realize efficient thermal convection and heat-conduction, and then fully guarantee the heat exchange of high temperature material and cooling water, can reach the cooling effect of preferred in the short time.

As a further improvement, the first water collecting tank and the second water collecting tank are of an annular structure, and the water collecting tank convenient to install on the barrel body at the two ends of the rotary kiln main body. Meanwhile, the heat exchange tubes are distributed along the circumferential direction of the inner cavity of the rotary kiln main body inner tube, the materials are located at the center of the cooling device, the materials in the rotary kiln main body are in full contact and heat exchange, and the outer wall of each heat exchange tube is in direct contact with the high-temperature materials, so that the heat exchange tubes are preferably made of wear-resistant stainless steel tubes, and the service life of the heat exchange tubes can be effectively prolonged.

As the utility model discloses a further improvement, install helical blade in the water-cooling jacket of rotary kiln main part, whole helical blade welds in interior barrel surface, can make the circulating water that lets in the water-cooling jacket reach turbulent state, has improved coefficient of heat transfer, reinforces the heat transfer. In addition, more optimally, a baffle plate assembly is arranged in the inner cavity of the rotary kiln body, so that materials in the rotary kiln can be lifted and turned over, and heat transfer is further enhanced.

As the utility model discloses a further improvement, the feed end of rotary kiln main part links to each other with feeding spiral subassembly, adopts spiral feeding structural style not only to avoid the material raise dust, leak the material, can guarantee moreover that the material evenly gets into the kiln body, ensures heat transfer effect. Simultaneously, the rotary kiln main part discharge end passes through movable seal subassembly and links to each other with the dustcoat, and the discharge gate has been seted up to the dustcoat bottom, and the material is discharged from the discharge gate through the dustcoat after the heat transfer in the rotary kiln main part intracavity. More optimally, still install guide helical blade in the activity seal assembly, and the installation of rotary kiln main part slope, its discharge gate is less than its feed inlet, and whole inclination is 0 ~ 5 to further do benefit to the material ejection of compact.

As the utility model discloses a further improvement, the rotary kiln main part is outside to link to each other with the motor reducer drive through chain drive subassembly, and through the rotational speed of the motor frequency control slewer of control slewer, the cooling time of adjustment material in the kiln to ensure material safety exit temperature.

As a further improvement, the supporting wheel supporting component is arranged on two sides of the main body of the rotary kiln, and plays a role in supporting the kiln body, and the kiln body can be prevented from moving around when rotating.

Compared with the prior art, the beneficial effects of the utility model are that:

the utility model discloses a cooling slewer compares with traditional cooling slewer: on one hand, under the same diameter, the heat exchange area under unit length is large, and the heat transfer efficiency is high; on the other hand, the utility model discloses cooling slewer can carry out indirect heat transfer with the material, effectively avoids producing a large amount of vapor, improves the site work environment greatly. In addition, the rotary device adopts a heat exchange mode of heat convection, heat conduction and heat radiation at the same time, and indirect contact and countercurrent modes are adopted between the materials and the cooling circulating water, so that the efficient cooling effect is achieved.

Drawings

Fig. 1 is a schematic structural view of an efficient cooling slewing device according to the present invention;

in the figure:

1. a feed screw assembly; 2. a first header tank; 3. an outer cylinder; 4. a helical blade; 5. a riding wheel support assembly; 6. an inner cylinder; 7. a heat exchange pipe; 8. a baffle assembly; 9. a second header tank; 10. a movable seal assembly; 11. a material guiding helical blade; 12. a housing; 13. a rotary joint; 14. a discharge port; 15. a water outlet assembly; 16. a water inlet assembly; 17. a motor reducer; 18. a chain drive assembly.

Detailed Description

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the scope of the present invention.

It is also to be understood that, unless otherwise explicitly stated or limited, the terms "mounted," "connected," and "connected" are to be construed broadly and may include, for example, fixed connections, removable connections, or integral connections; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The present invention will be further described with reference to the following specific embodiments.

Example 1

As shown in fig. 1, the high-efficiency cooling rotary device of the embodiment comprises a rotary kiln body, a first water collecting tank 2 and a second water collecting tank 9 which are symmetrically arranged at two ends of the rotary kiln body, and a heat exchange pipe 7 arranged in an inner cavity of the rotary kiln body. The two ends of the heat exchange tube 7 are respectively communicated with the first water collecting tank 2 and the second water collecting tank 9, so that cooling water in the water collecting tubes can be conveyed into the heat exchange tube 7, and high-temperature materials in the rotary kiln main body can exchange heat with the heat exchange tube 7. More optimally, the utility model discloses in process first header tank 2, second header tank 9 and process into the loop configuration, be convenient for install it at rotary kiln main part both ends, do not influence the normal work of rotary kiln main part.

Additionally, the utility model discloses a heat transfer part is except heat exchange tube 7, still includes the water-cooling clamp cover that the outer barrel 3 of rotary kiln main part and interior barrel 6 formed, and the rotary kiln main part adopts double-deck tubular structure, and the water-cooling clamp cover that forms between inside and outside urceolus still is linked together with first header tank 2.

The utility model discloses a with the ingenious combination of heat exchange tube 7 and rotary kiln main part, can effectively improve cooling efficiency, promote the cooling effect, simultaneously, the utility model has the advantages of simple overall structure, need not to set up other equipment and device in the rotary kiln outside to effectively solved because of traditional slewer cooling arrangement is bulky and take up the big problem in space. More optimally, the utility model discloses a leave the clearance between including, the urceolus to form the water-cooling and press from both sides the cover and be linked together with the header tank, can be through pressing from both sides the cover and the heat exchange tube 7 between letting in the cooling water to this water-cooling, when cooling down the high temperature material, material and interior barrel wall direct contact, greatly increased heat transfer area, improved heat exchange efficiency.

Example 2

The main structure of the high-efficiency cooling rotary device of the present embodiment is basically the same as that of embodiment 1, and the main differences are as follows: first header tank 2 locates rotary kiln main part feed end department, and rotary kiln body discharge end department is located to second header tank 9, promptly, as shown in the orientation in fig. 1, the utility model provides a first header tank 2 installs in the front portion of rotary kiln main part, and second header tank 9 installs the afterbody in the rotary kiln main part. Meanwhile, the rotary kiln also comprises a water inlet assembly 16 and a water outlet assembly 15 which are arranged on the rotary kiln body. The water inlet assembly 16 and the water outlet assembly 15 are both arranged at the tail discharge end of the rotary kiln body, and the water outlet assembly 15 is used for discharging the water after heat exchange or cooling the water after heat exchange to be used as circulating water for recycling.

In addition, the water inlet assembly 16 of the present invention is connected to an external cooling water supply device through a pipe and a rotary joint 13. The rotary joint 13 is also designed to be of a jacket type structure, the inside of the rotary joint is provided with a water inlet passage which is communicated with a water inlet assembly 16, and the outside of the rotary joint 13 is provided with a water outlet passage which is communicated with a water outlet assembly 15. Through setting up rotary joint 13 and carrying out optimal design to its concrete structure, under the rotatory condition of rotary kiln main part, not only can guarantee that subassembly 16 and outside water supply installation of intaking are connected, guarantee the stability of supplying water, can also guarantee to go out water stably. It is worth explaining, the utility model discloses a design into subassembly 16 and go out the connected mode that water subassembly 15 respectively with header tank, water-cooling pressed from both sides the cover, can control cooling water flow direction in heat exchange tube 7 and the water-cooling pressed from both sides the cover, all can realize letting in cooling water in to above-mentioned cooling part, finally realize the cooling action to the interior high temperature material of rotary kiln main part.

Furthermore, in order to ensure a more efficient cooling effect in the present embodiment, the water outlet assembly 15 is communicated with the water cooling jacket of the rotary kiln body by communicating the water inlet assembly 16 with the second water collecting tank 9. Therefore, cooling water can enter the heat exchange tube 7 from the second water collecting tank 9 and then enter the water cooling jacket through the first water collecting tank 2, so that when materials contact the heat exchange tube 7 in the rotary kiln, the materials and the cooling water perform countercurrent heat exchange, the heat exchange efficiency is obviously improved, efficient heat convection and heat conduction are realized, the heat exchange of high-temperature materials and the cooling water is fully ensured, and the better cooling effect can be achieved in a short time.

Example 3

The main structure of a high-efficiency cooling rotary device of this embodiment is basically the same as that of embodiment 2, and the main differences are as follows: first header tank 2 and second header tank 9 are the loop configuration, for the convenience install the header tank in the rotary kiln main part to and make the structure of header tank and rotary kiln more adaptation, design first header tank 2 and second header tank 9 for above-mentioned structure, do not actually restrict its shape, only need it satisfy catchments and carry the function that cooling water carried to heat exchange tube 7 and water-cooling jacket can. More optimally, in the embodiment, the heat exchange tubes 7 are distributed along the circumferential direction of the inner cavity of the inner cylinder of the rotary kiln body, the material is positioned at the center of the heat exchange part, and the distribution condition of the heat exchange part around the material is formed, so that the material is ensured to be in contact with the heat exchange part constantly, efficient heat convection and heat conduction are realized, and when the temperature of the material is higher, the heat radiation also occupies a certain proportion. In addition, because the heat exchange tube 7 is located inside the rotary kiln main part, its lateral wall is direct and high temperature material contact, can gain very outstanding cooling effect, but inevitably, can take place wearing and tearing in the long-term use, simultaneously, treat that refrigerated material still has higher temperature, consequently, the heat exchange tube 7 of this embodiment adopts wear-resisting stainless steel pipe to make to guaranteed good wear resistance, and then promoted its life, guarantee that production goes on in succession, reduce cost of maintenance, be favorable to improving enterprise economic benefits.

In addition, more optimally, on one hand, the helical blade 4 is installed in the water-cooling jacket of the rotary kiln main body, the helical blade 4 is welded on the outer surface of the inner cylinder body 6 of the rotary kiln main body, and the circulating cooling water can reach a turbulent flow state through the arrangement of the helical blade 4, so that the heat transfer coefficient is improved, and the heat exchange is enhanced. On the other hand, a baffle plate assembly 8 is arranged in the inner cavity of the rotary kiln body, the baffle plate assembly 8 comprises a baffle plate and a shoveling plate, and in the using process, the shoveling plate can lift and turn over the materials along with the rotation of the rotary kiln body, so that the heat transfer is further enhanced.

Example 4

The main structure of the high-efficiency cooling rotary device of the present embodiment is basically the same as that of embodiment 3, and the main differences are as follows: the feed end of rotary kiln main part links to each other with feeding spiral subassembly 1, and the material is through feeding spiral subassembly 1 in the at the uniform velocity gets into a section of thick bamboo from rotary kiln body front end, adopts spiral feeding structural style not only to avoid the material raise dust, leak material, guarantees the even entering kiln body of material moreover, ensures heat transfer effect. Meanwhile, the discharge end of the rotary kiln body is connected with the outer cover 12 through the movable sealing component 10, the discharge hole 14 is formed in the bottom of the outer cover 12, the movable sealing component 10 can be sealed through elastic radial combined type group pieces, the sealing effect is good, and the rotary kiln body can be effectively used for sealing of a rotary device. Furthermore, a material guiding helical blade 11 is further installed in the movable sealing assembly 10, so that the material is conveniently conveyed and discharged.

In addition, more optimize, the rotary kiln main part adopts the slope installation, and its discharge gate is less than its feed inlet, and whole inclination is 0 ~ 5, and the feed end through controlling whole rotary kiln main part is higher than its discharge end, and the material is very easy to move to the discharge end by oneself under the effect of self gravity to the ejection of compact of being convenient for.

The outer side of the outer cylinder 3 of the rotary kiln main body of the embodiment is fixedly provided with a chain transmission assembly 18, the chain transmission assembly 18 is arranged on the kiln body in a tangential installation mode and is in driving connection with a motor reducer 17, and the motor reducer 17 is used as a power source to drive the kiln body to rotate. The motor speed reducer 17 adopts frequency conversion, and the rotating speed of the rotating device is controlled by controlling the motor frequency of the rotating device (namely the rotary kiln main body), so that the cooling time of the material in the kiln is conveniently adjusted, and the temperature of a material safety outlet is ensured. Preferably, the inner and outer cylinders of the rotary kiln body of this embodiment are formed with cooling jackets, so that the chain drive assembly 18 can be kept at a safe use temperature.

In addition, the cooling rotary device also comprises supporting wheel supporting components 5, the supporting wheel supporting components 5 are arranged at the front end and the rear end outside the rotary kiln main body, the supporting wheel supporting components 5 are composed of supporting wheel components and supporting and blocking wheel components, the effect of supporting the rotary kiln body is achieved, meanwhile, the rotary kiln body can be prevented from moving forwards and backwards during rotation, and the supporting structure is simple and easy to install.

The utility model discloses a cooling slewer's theory of operation and working process as follows:

high temperature material gets into the slewer left end through feeding spiral component 1, and the high temperature material after getting into carries out the heat exchange simultaneously with heat exchange tube 7, interior barrel 6, and baffle subassembly 8 in the slewer plays the effect of guide, material raising, improves heat transfer efficiency. The material reaching the design outlet temperature is collected centrally by the rear housing 12 at the outlet 14. The cooling medium circulating water enters the water inlet assembly 16 through the rotary joint 13 and then converges in the second water collecting tank 9, the circulating water is uniformly distributed in the second water collecting tank 9 and then enters the heat exchange tube 7, the circulating water after heat exchange by the heat exchange tube 7 enters the first water collecting tank 2, the circulating water flows into the water-cooling jacket formed by the inner barrel 6 and the outer barrel 3 after the hole is formed in the barrel wall of the first water collecting tank 2, and finally the circulating water is gathered by the water outlet assembly 15 and flows out of the rotary joint 13. The material and the circulating water form countercurrent, the heat exchange efficiency is high, the structure is simple, the rotating speed is adjustable, and the maintenance is convenient.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. The utility model provides an efficient cooling slewer, includes the rotary kiln main part, its characterized in that: also comprises a first water collecting tank (2), a second water collecting tank (9) and a heat exchange pipe (7), wherein,

the first water collecting tank (2) and the second water collecting tank (9) are respectively and symmetrically arranged at two sides of the rotary kiln body;

the heat exchange tube (7) is arranged in the rotary kiln body, and two ends of the heat exchange tube (7) are respectively connected with the first water collecting tank (2) and the second water collecting tank (9) on two sides of the heat exchange tube;

the rotary kiln main body adopts a double-layer cylinder structure, and a water-cooling jacket formed between the inner cylinder and the outer cylinder is communicated with the first water collecting tank (2).

2. A high efficiency cooling slewing device as defined in claim 1, wherein: first header tank (2) are located rotary kiln main part feed end department, and rotary kiln body discharge end department is located in second header tank (9).

3. A high efficiency cooling slewing device as defined in claim 1, wherein: the rotary kiln is characterized by further comprising a water inlet assembly (16) and a water outlet assembly (15) which are arranged on the rotary kiln main body, wherein the water inlet assembly (16) and the water outlet assembly (15) are both arranged at the discharge end of the rotary kiln body, and the water inlet assembly (16) is connected with an external cooling water supply device through a pipeline and a rotary joint (13).

4. A high efficiency cooling slewing device according to claim 3, wherein: the water inlet assembly (16) is communicated with the second water collecting tank (9), and the water outlet assembly (15) is communicated with a water-cooling jacket of the rotary kiln body on one hand and is also communicated with the rotary joint (13) on the other hand.

5. A high efficiency cooling slewing device according to any one of claims 1-4, characterized in that: the first water collecting tank (2) and the second water collecting tank (9) are of annular structures, the heat exchange tubes (7) are distributed along the circumferential direction of the inner cavity of the rotary kiln main body inner barrel, and the heat exchange tubes (7) are made of wear-resistant stainless steel tubes.

6. A high efficiency cooling slewing device according to any one of claims 1-4, characterized in that: and a helical blade (4) is arranged in a water-cooling jacket of the rotary kiln main body, and a baffle plate assembly (8) is arranged in an inner cavity of the rotary kiln main body.

7. A high efficiency cooling slewing device according to any one of claims 1-4, characterized in that: the feeding end of the rotary kiln main body is connected with the feeding spiral component (1), the discharging end of the rotary kiln main body is connected with the outer cover (12) through the movable sealing component (10), and the bottom of the outer cover (12) is provided with a discharging hole (14).

8. A high efficiency cooling slewing device as defined in claim 7, wherein: and a material guiding helical blade (11) is also arranged in the movable sealing assembly (10).

9. A high efficiency cooling slewing device according to any one of claims 1-4, characterized in that: the rotary kiln body is obliquely arranged, a discharge port of the rotary kiln body is lower than a feed port of the rotary kiln body, the integral inclination angle is 0-5 degrees, and the outer part of the rotary kiln body is in driving connection with a motor reducer (17) through a chain transmission assembly (18).

10. A high efficiency cooling slewing device according to any one of claims 1-4, characterized in that: the rotary kiln is characterized by further comprising two supporting wheel supporting assemblies (5), wherein the two supporting wheel supporting assemblies (5) are arranged on two sides of the outer portion of the rotary kiln body.