US3307621A

US3307621A - Heat transfer apparatus

Info

Publication number: US3307621A
Application number: US421808A
Authority: US
Inventors: John K Whisnant; Roger A Dysart
Original assignee: Fiber Industries Inc
Current assignee: Celanese Corp
Priority date: 1964-12-29
Filing date: 1964-12-29
Publication date: 1967-03-07
Anticipated expiration: 1984-03-07
Also published as: ES320824A1; NO119608B; AT280462B; BE674472A; FR1462078A; DE1660298B2; GB1116436A; DK116304B; DE1660298A1; NL6516998A

Description

March 7,1967; J. K. WHIVSNANT ETAL Q 3,

' HEAT TRANSFER APPARATUS FiledDec. 29, 1964 s Sheets-Sheet 1 Afro/nay March 1967 J. K. WHISNANT YETAL 3,307,621

HEAT TRANSFER APPARATUS Filed Dec. 29, 1964 3 Sheets-Sheet 2 //vl//v 70/?5 Jahn A. Wh/snarz/ Roger A. Dyson Afro/nay March 19.67 J. K. WHISNANT ETAL 3,307,621

HEAT TRANSFER APPARATUS Fil ed Dec. 29, 1964 3 sheets sheet 3 //V VE/VTORS John K W/v/snon/ Roger A Oysar/ A Nor/76y United States Patent 3,307,621 HEAT TRANSFER APPARATUS John K. Whisnant and Roger A. Dysart, Shelby, N.C., assignors to Fiber industries, Inc., a corporation of Delaware Filed Dec. 29, 1964, Ser. No. 421,808 Claims. (Cl. 16589) This invention is directed to an improved heat transfer apparatus. More particularly, the invention is directed to an improved unit of uniformly heated rolls and to an improved heat transfer roll.

In the production of synthetic fibers, the extruded polymers such as nylon, polypropylene, polyethylene terephthalate in the form of filaments, generally, do not at this stage have the desired physical properties for suitable use in their final fiber form for the production of fabrics in the textile or industrial areas. These extruded filaments must be further processed to impart full strength, durability, denier control and the like. One important part of this further processing is known as drawing or drawtwisting which includes stretching the yarn, twisting, kinking or texturizing. All of these stretching operations should be performed under precisely controlled temperature conditions.

The most critical problem in performing these operations is to heat the yarn to the desired temperature level to properly relax the long molecular chains resulting in maximum strength and stability. The equipment widely used to accomplish this purpose is stationary heated platens or blocks to heat the fibers. These methods of heating fibers have considerable disadvantages of short contact times and problems created by friction, among others.

Attempts to overcome these problems have been directed to the heating of the yarns on the draw rolls but this procedure has not been completely satisfactory because of the difficulty of temperature control. The usual method of heating rolls is by electrical heating units with suitable controls in each individual roll and transfer of heat through a short space of air. Under these conditions, it has been found difficult to control the temperature precisely. The thermal lags of heat transfer to the roll are formidable and are the major deterrent to the approach. To overcome these problems, numerous unsuccessful attempts have been made to provide uniformly heated rolls for the drawing or draw-twisting operations.

It is the object of this invention to provide unique and economically attractive units of uniformly heated rolls which overcome the predominant disadvantages of the above-described heated rolls. A further object is to provide an improved heat transfer apparatus which makes up an individual part of the units of uniformly heated rolls.

Other objects and advantages will become more apparent to those skilled in the art by reference to the disclosure of the preferred embodiments in the specification, claims and drawings in which:

FIGURE 1 represents a perspective schematic of a unit of heated rolls arranged in series as used in a drawtwister operation;

FIGURE 2 is a cross-sectional side view of an individual heated roll in the unit of heated rolls of FIGURE 1;

FIGURE 3 is a front-sectional view taken along lines 3-3 of FIGURE 2.

FIGURE 1 represents a draw-twister apparatus incorporating a unit of uniformly heated rolls as claimed. The main inlet means 10 for the flow of heat conducting materials from the heating source, as indicated in the drawing, supplies the heating means under a slight pressure to the plurality of feeder rolls 11 through the individual inlet means 12 to the heating core within the rotatable or feeder rolls 11. The heat conducting material is withdrawn from the heating core through the individual outlet means 13 by means of the differential of pressure of the heat conducting material in the main inlet means 10 and individual inlet means 12 to the main outlet means 14. Through the main outlet means the heat conducting material is returned to the heating source, as shown. It should be noted that the excess heat conducting material which does not pass through the heating core to heat rollers 11 is returned to the heating source through line 10 along with the material used to heat the rollers 11. If it is'desired, heating elements 15 such as indicated, can be included at appropriate places on the main inlet and outlet lines. Bobbins of undrawn yarns are arranged in such a manner so as to permit the undrawn yarn to pass over the individual heated rollers 11 and to pass on to its respective unnumbered roller which is running at a higher speed than the heated rollers 11 to provide a stretching effect of the yarn to provide strength properties. The string-up of the yarn from the feed bobbin to the collection bobbin is described in the prior art and has not been shown in FIG- URE 1 in order to avoid confusion whileemphasizing the method of heating a plurality of rolls.

FIGURE 2 represents a cross-section of a preferred embodiment of the improved individual heat transfer apparatus as claimed herein which can be used in the unit as described in FIGURE 1. A hollow rotatable roll 16 which can be used primarily for heating filamentary material by passing the yarns or filaments over or around the outside surface of the roll 16, has a connecting rotatable shaft 17 to provide the desired rotating movement. A back plate 18 is attached to the rear portion of the hollow rotatable roll 16. The back plate 18 has an annular trough 19 extending inwardly toward the hollow portion of the roll 16. The back plate 18 is shaped in such a way so that a drip ring assembly 20 which is placed on the stationary heat radiating core 21 will prevent the escape of the heat conducting material 22 from the inside of the hollow portion of roller 16. The stationary heat radiating core 21 is projected within the hollow portion of roller 16 and the core 21 is shaped so as to substantially conform to the hollow shape of roller 16 and at the same time surround the rotatable shaft 17. Within the heating core 21 is a passageway 23 for the flow of heat conducting materials which in turn heats core 21. The flow of heat conducting materials for the heating of core 21 is introduced from the main inlet means (not shown) through the inlet means 24 and is removed to the main outlet means (not shown) through the outlet means (not shown) in FIGURE 2. The flow of the heat conducting means through the passageway 23 of core 21 transfers the heat through core 21 to the heat conducting material 22 which intimately contacts the outer portion of the stationary heat radiating core 21 and the inner wall of the hollow rotatable roll 16. The heat conducting material 22 is uniformly distributed by centrifugal force on the turning of the roll 16. It should be noted by this system, that an extremely high efiiciency of heat transfer is available since there are no air spaces to hinder or disrupt the heat transfer. A guard 25 is placed around the back plate 18 of rotatable roll 16 to prevent the heat conducting material 22 from escaping from the roll 16 and contaminating the products being heated on the outer surface of roll 16.

FIGURE 3 is a front-sectional view taken along lines 33 of FIGURE 2 showing the inlet means 24 for the flow of heat conducting materials connecting with passageway 23 and passing out at the outlet means 26. It should be noted that the non-vapor heat conducting ma terial 22 within the rotatable roll 16 is maintained between the inner Wall of roll 16 and the outer portion of the stationary heat radiating core 21 in a uniform layer by centrifugal force on the rotating of roll 16. When roll 16 ceases to rotate, a reservoir 27 is available for the nonvapor heat conducting material 22.

The materials which can be used in the manufacture of the rotatable roll and the heat radiating stationary core can include those materials which readily transfer heat and are known in the art for roller production such as mild steel, stainless steel, aluminum, brass, etc.

The heat conducting materials which can be utilized in the rotatable roll are non-vapor materials including suitable and preferably liquids such as high temperature resistant lubricating oils, molten metal and the like. It is conceivable to utilize finely powdered or minute balls of heat conducting materials or combinations of finely powdered or minute balls of heat conducting materials and suitable liquids. It is essential, however, for these purposes that the heat conducting materials in the roll will be uniformly distributed on the inside of the surface of the roll and will not interfere with the rotation of the roll.

The means of heating the stationary heating core in the apparatus of this invention can be by electrical heating units or preferably by heat conducting materials passing through the core such as heating vapors or heating liquids.

The heat conducting materials used to heat or cool the heat radiating core can include a variety of materials such as lubricating oils, molten metal, dowtherm, steam, etc. to obtain the desired effect. The preferable method is to utilize a suitable heating vapor such as steam or a high temperature resistant lubricating oil. It should be obvious to one skilled in the art that the method of heating large quantities of fluids provides one of the best types of control of temperature for minimum fluctuations.

The apparatus, as claimed herein, when used in a drawtwisting operation, especially for polyethylene terephthalate yarns or filaments, provides high uniform products such as uniform shrinkage properties, the same physical properties etc. because of the maintenance of constant temperatures used throughout the unit of feeder rolls as described herein.

It is to be understood that the foregoing description is merely illustrative of preferred embodiments of the invention of which many variations may be made by those skilled in the art within the scope of the following claims without departing from the spirit thereof.

What is claimed is:

1. A unit of uniformly heated rolls comprising a plurality of roll units wherein each of said roll units comprises a hollow rotatable roll, a stationary heat radiating core, said core projected within the hollow portion of said hollow rotatable roll substantially conforming to the shape of said hollow portion, means for heating said core and non-vapor heat conducting fluid-like material self contained within said hollow rotatable roll uniformly distributed and intimately contacting the inner wall of said hollow rotatable roll and outer portion of said stationary core projected within said hollow rotatable roll by centrifugal force while the roll is turning.

2. A unit of uniformly heated rolls comprising a plurality of roll units wherein each of said roll units comprises a hollow rotatable roll, a stationary heat radiating core containing a passageway for the flow of heat conducting materials, said core projected within the hollow portion of said hollow rotatable roll substantially conforming to the shape of said hollow portion, inlet and outlet means connected to the passageway in said core for the flow of heat conducting materials and non-vapor heat conducting fluid-like material self contained within said hollow rotatable roll uniformly distributed and intimately contacting the inner wall of said hollow rotatable roll and outer portion of said stationary core projected within said hollow rotatable roll by centrifugal force while the roll is turning; a main inlet means connected to each individual inlet means within the stationary heating core of each individual hollow rotatable roll for the flow of heat conducting materials from the heating source and a main outlet means connected with each individual outlet means within the stationary heating core of each individual hollow rotatable roll for the return flow of heat conducting materials to the heating source.

3. A unit of uniformly heated rolls comprising a plurality of roll units wherein each of said roll units comprises a hollow rotatable roll, a stationary heat radiating core containing a passageway for the flow of liquid heat conducting materials, said core projected within the hollow portion of said hollow rotatable roll substantially conforming to the shape of said hollow portion, inlet and outlet means connected to the passageway in said core for the flow of liquid heat conducting materials and liquid heat conducting materials self contained within said hollow rotatable roll uniformly distributed and intimately contacting the inner wall of said rotatable roll and outer portions of said stationary core within said hollow rotatable roll by centrifugal force while the roll is turning; a main inlet means connected to each individual inlet means within the stationary heating core of each individual hollow rotatable roll for the flow of liquid heat conducting materials from the heating source and a main outlet means connected with each individual outlet means within the stationary heating core of each individual hollow rotatable roll for the return flow of liquid heat conducting materials to the heating source.

4. A unit of uniformly heated rolls comprising a plurality of roll units wherein each of said roll units comprises a hollow rotatable roll, a stationary heat radiating core containing a passageway for the flow of liquid heat conducting materials, said core projected within the hollow portion of said hollow rotatable roll substantially conforming to the shape of said hollow ortion, inlet and outlet means connected to the passageway in said core for the flow of vapor heat conducting materials and liquid heat conducting materials self contained within said hollow rotatable roll uniformly distributed and intimately contacting the inner wall of said rotatable roll and outer portions of said stationary core within said hollow rotatable roll by centrifugal force while the roll is turning; a main inlet means connected to each individual inlet means within the stationary heating core of each individual hollow rotatable roll for the flow of vapor heat conducting materials from the heating source and a main outlet means connected with each individual outlet means within the stationary heating core of each individual hollow rotatable roll for the return flow of vapor heat conducting materials to the heating source.

5. A unit of uniformly heated rolls comprising a plurality of roll units wherein each of said roll units comprises a hollow rotatable roll containing a rotatable shaft, a back plate attached to said hollow rotatable roll, a stationary heat radiating core containing a passageway for the flow of heat conducting materials, said core projected within the hollow portion of said hollow rotatable roll substantially conforming to the shape of said hollow portion and surrounding the rotatable shaft projecting from said hollow rotatable roll, inlet and outlet means connected to the passageway in said core for the flow of heat conducting materials, non-vapor heat conducting fluid self contained within said hollow rotatable roll uniformly distributed and intimately contacting the inner Wall of said hollow rotatable roll and outer portions of said stationary core within said hollow rotatable roll by centrifugal force while the roll is turning; a drip ring assembly of opposed portions located on said stationary core and confronting said back plate of said hollow rotatable roll as to maintain and prevent leakage of fluids within said hollow rotatable roll, a main inlet means connected with each individual inlet means within the stationary heating core of each individual hollow rotatable roll for the fiow of heat conducting materials from the heating source and a main outlet means connected with each individual outlet means within the stationary heating core of each individual hollow rotatable roll for the return flow of heat conducting materials to the heating source.

6. A heat transfer apparatus comprising a hollow rotatable roll, a stationary heat radiating core, said core projected within the hollow portion of said hollow rotatable roll substantially conforming to the shape of said hollow portion, means for heating said core and nonvapor heat conducting fluid-like material self-contained within said hollow rotatable roll uniformly distributed and intimately contacting the inner wall of said hollow rotatable roll and outer portion of said stationary core projected within said hollow rotatable roll by centrifugal force while the roll is turning.

7. A heat transfer apparatus comprising a hollow rotatable roll, a stationary heat radiating core containing a passageway for the flow of heat conducting materials, said core projected with the hollow portion of said hollow rotatable roll substantially conforming to the shape of said hollow portion, means to conduct heat to and from said core, means to supply and withdraw heat conducting materials from the passageway of said core, and non-vapor heat conducting fluid-like material self-contained within said hollow rotatable roll uniformly distributed and intimately contacting the inner wall of said hollow rotatable roll and outer portion of said stationary core within said hollow rotatable roll by centrifugal force while the roll is turning.

8. A heat transfer apparatus comprising a hollow rotatable roll containing a rotatable shaft, a stationary heat radiating core containing a passageway for the flow of heat conducting materials, said core projected within the hollow portion of said hollow rotatable roll substantially conforming to the shape of said hollow portion, and said core completely surrounding said rotatable shaft projecting from said hollow rotatable roll, inlet and outlet means connected to the passageway in said core for the flow of heat conducting fluids and non-vapor heat conducting material self-contained within said hollow rotatable roll uniformly distributed and intimately contacting the inner wall of said hollow rotatable roll and outer portion of said stationary core within said hollow rotatable roll by centrifugal force while the roll is turning.

9. A heat transfer apparatus comprising a hollow rotatable roll containing a rotatable shaft, a back plate attached to said hollow rotatableroll, a stationary heat radiaing core containing a passageway for the flow of heat conducting material, said core projected within the hollow portion of said hollow rotatable roll substantially conforming to the shape of said hollow portion and surrounding the rotatable shaft projecting from said hollow rotatable roll, heat conducting fluid self-contained within said hollow rotatable roll uniformly distributed and intimately contacting the inner wall of said hollow rotatable roll and outer portion of said stationary core within said rotatable roll by centrifugal force while the roll is turning, and a drip ring assembly located on said stationary core confronting said back plate to maintain and prevent leakage of fluids within said hollow rotatable roll.

10. The apparatus of claim 9 wherein the heat conducting fluid within the hollow rotatable roll is a lubricating oil.

References Cited by the Examiner UNITED STATES PATENTS 2,873,538 2/1959 Shumaker -89 X 3,022,047 2/ 1962 Swaney 165-89 3,238,592 3/1966 Killoran et al. 2871 X FOREIGN PATENTS 1,186,750 2/1959 France.

1,323,071 2/1963 France.

ROBERT A. OLEARY, Primary Examiner. MEYER PERLIN, Examiner. T. W. STREULE, Assistant Examiner.

Claims

1. A UNIT OF UNIFORMLY HEATED ROLLS COMPRISING A PLURALITY OF ROLL UNITS WHEREIN EACH OF SAID ROLL UNITS COMPRISES A HOLLOW ROTATABLE ROLL, A STATIONARY HEAT RADIATING CORE, SAID CORE PROJECTED WITHIN THE HOLLOW PORTION OF SAID HOLLOW ROTATABLE ROLL SUBSTANTIALLY CONFORMING TO THE SHAPE OF SAID HOLLOW PORTION, MEANS FOR HEATING SAID CORE AND NON-VAPOR HEAT CONDUCTING FLUID-LIKE MATERIAL SELF CONTAINED WITHIN SAID HOLLOW ROTATABLE ROLL UNIFORMLY DISTRIBUTED AND INTIMATELY CONTACTING THE INNER WALL OF