US3494603A

US3494603A - Apparatus for the controlled cooling of hot rolled steel rod

Info

Publication number: US3494603A
Application number: US453312A
Authority: US
Inventors: William J Hill
Original assignee: Morgan Construction Co
Current assignee: Siemens Industry Inc
Priority date: 1965-05-05
Filing date: 1965-05-05
Publication date: 1970-02-10
Anticipated expiration: 1987-02-10
Also published as: NO126512B; LU51028A1; BE680425A; AT307348B; NL154786B; NL6605925A; JPS4831446B1; ES326670A1; FI50841C; FI50841B; GB1128350A; DE1527818A1; SE317345B

Description

w. J. mu. 3,494,603

APPARATUS FOR THE CONTROLLED COOLING 0F HOT ROLLED STEEL ROD Feb. 10, 1970 13 Sheeis-Shet 1 Filed May 5, 1965 Na N9 INVENTOR.

Hill m I a N 3 3 w n m 2 +1 2 3 3 mv vb. v 11 1 m 0 B Q WW f vb ww mm 7., mhmfi l I} I IBM] ME w r a w a 5 3 J S x v Q EN EN Feb. 10, 1970 "3,494,603

APPARATUS FOR THE CONTROLLED COOLING 0F HOT ROLLED STEEL Rm) 7 Filed May 5, 1965 w. J. mu,

1: Sheets-She et a v INVENTOR ZU'I'ZZI'am HI'ZZ orneys Feb. 10, 1970 w. J. HILL I 3.4

APPARATUS FOR THE CONTROLLED COOLING OF HOT ROLLED STEEL ROD I Filed May 5. 1965 1 3 Sheets-Sheet s INVENTOR.

Feb. 10, 1970 w. J. mu. 3,494,603

APPARATUS FOR THE CONTROLLED COOLING OF HOT ROLLED STEEL ROD I Filed May 5. 1965 13' Sheets-Sheet 4 4 INVENTOR. )3 zz/zzz dm gfljzz Q' www N N Hum Feb. 10,1910 W.JI.HIILL 3,494,6 3

APPARATUS FOR THE CONTROLLED COOLING OF HOT ROLLED STEEL ROD IN VEN TOR.

v Hm

w; J. HILL 3,494,603

APPARATUS FOR THE CONTROLLED COOLING 0F HOT ROLLED STEEL ROD Feb. 10, 1970 13 Sheets-Sheet 6 Filed May 5, 1965 ZI/il l jam Hill BY M W ,W

H orneys w. J. mu. 3,494,603 APPARATUSFOR THE CONTROLLED COOLING 0F HOT ROLLED STEEL ROD I "13 Sheets-Sheet '7 Feb. 10, 1970 Filed May 5, 1965 g. QR

orneys MS in wnN 2w I'fl {Hil I I'IIE Feb. 10, 1970 3,494,603

APPARATUS FOR THE CONTROLLED COOLING OF HOT ROLLED STEEL ROD Filed May 5, 1965 w. J. mm.

13 Sheets-Sheet 8 INVENTOR.

Feb. 10, 1970 w. J. HILL 7 3,

APPARATUS FOR THE CONTROLLED COOLING OF HQT' ROLLED STEEL RODv Filed May 5, 1965 13 Sheets-Sheet 9' "'3 N r; Y N N N I 5 WE I I a a! w U' g3 "11 R} w 1' g? I Q N I N o J g 8 a L l s Q 3 O INVENTOR. 1 L William HI'ZZ Feb. 10, 1970 w. J. HILL 3,494,603.

APPARATUS FOR THE CONTROLLED COOLING OF HOT ROLLED STEEL ROD Filed Maya, 1965 13 Sheets-Sheet 1o 3 INVENTOR. wjzzzdm 2. Hill APPARATUS FOR THE CONTROLLED COOLING 0F HOT ROLLED STEEL ROD Filed May 5, 1965 W. J. HILL Feb. 10; 1970 13 Sheets -Sheet 11 5 Z m 6y mflw m W 0 m m ME w. J. mu. 3, 9 0

APPARATUS FOR THE CONTROLLED COOLING OF HOT ROLLED STEEL ROD Feb. 10, 1970 13 Shets-Shegt 1:

Filed May 5, 1965 w mNN Feb. 10, 1970 w. J. mu. 3,494,503

APPARATUS FOR THE CONTROLLED COOLING 0F HQ'I' ROLLEb STEEL ROD I Filed May 5, 1965 1s Sheets-Sheet 15 INVENTOR. ZZ/I'ZZI'dm gzzz United States Patent ()1 hoe 3,494,603 APPARATUS FOR THE CONTROLLED COOLING OF HOT ROLLED STEEL ROD William J. Hill, Holden, Mass., assignor to Morgan Construction Company, Worcester, Mass., a corporation of Massachusetts Filed May 5, 1965, Ser. No. 453,312

Int. Cl. C21d 9/52 US. Cl. 266-3 17 Claims ABSTRACT OF THE DISCLOSURE This invention relates to rolling mills producing hot rolled steel rod and more particularly to an improved apparatus for cooling rod at a controlled rate in direct sequence with the rolling operation.

An important technological advance in the steel industry has recently demonstrated both the desirability and feasibility of cooling rod in direct sequence with a rolling operation in order to impart predetermined metallurgical properties to the rod along its entire length. A description of this new development, which will hereinafter be referred to for convenience of reference as the McLean- Easter process, appears in US. patent application Ser. No. 402,495, now Patent No. 3,231,432, issued Ian. 25, 1966. The McLean-Easter process teaches the method of preparing steel rod for subsequent cold working by performing a controlled cooling operation on the rod as it emerges from the final finishing stand of the mill. The cooling (often referred to as quenching) is done at mill speed in such a way that a substantially uniform metallurgical structure is imparted to the rod along its entire length with an accompanying reduction in scale loss and without formation of detrimental constituents such as martensite.

At present, the McLean-Easter process is practiced by depositing the rod in nonconcentric overlapping rings on a moving conveyor. The conveyor is provided with a relatively open framework which permits free circulation of the cooling medium while still furnishing adequate support for the overlapping rod rings. Controlled condi tions are achieved by regulating the flow rate of coolant through the conveyor and/or by varying the type of coolant utilized. Experience has shown that use of the Me- Lean-Easter process results in the attainment of a product having uniform metallurgical properties suitable for subsequent cold working without the need for an intermediate annealing or patenting step.

The present invention relates to an alternate and improved apparatus for practicing the McLean-Easter process and has as one of its objects the attainment of a more uniform exposure of rod surface to the cooling medium. Other objects of the present invention include greater flexibility and closer control over the cooling operation.

The foregoing objects are achieved in the present invention by arranging high temperature rod issuing from the mill in a continuous series of nontouching but closely adjacent concentrically aligned rings. The rings are appropriately supported by an axially disposed perforated tubular carrying structure. With the rings arranged in a Patented Feb. 10, 1970 nontouching relationship, a more uniform exposure to the cooling medium is made possible by avoiding ring overlapping. Moreover, pressurized coolant is radially applied to the exposed surfaces of the rod rings in a uniform manner around the entire circumference of the tubular carrying structure. Finally, where circumstances warrant, the tubular carrying structure may be combined with additional means including an outer housing for closely controlling the amount and/or type of coolant being applied to the rod rings. This latter feature is particularly useful where the mill is rolling a wide range of rod sizes.

The invention will hereinafter be described in connection with the controlled cooling of hot rolled steel rod. It is to be understood, however, that this reference to a particular type of product is for illustrative purposes only and is not intended as a limitation upon the scope of the claims appended hereto. In actuality, the invention may be practiced with any hot rolled steel product capable of being formed into a continuous series of rings by a rotating laying ahead. Thus, as herein utilized, the term rod is intended to include all such products.

The nature of the invention will become more apparent as the description proceeds with the aid of the accompanying drawings in which:

FIG. 1 is a plan view of one embodiment of the invention with a portion ofthe outer housing structure partially cut away to show a series of concentrically aligned rod rings moving axially along an inner cantilevered arm member;

FIG. 2 is .a side elevational view of the apparatus as shown in FIG. 1 with cooled rod rings dropping from the delivery end of the cantilevered arm member onto a coil forming apparatus;

FIG. 3 is an enlarged plan view of the apparatus shown in FIG. 1 with the mid-portion cut away and with the outer housing structure removed in order to illustrate an alternate possible use of the invention;

FIG. 4 is an enlarged horizontal sectional view taken along line 44 of FIG. 2;

FIG. 5 is a longitudinal sectional view of the cantilevered arm member prior to its connection to the laying head;

FIG. 6 is a sectional view of the arm member taken along lines 6-6 of FIG. 3;

FIGS. 7 and 8 are sectional views of the arm member taken along lines 7-7 and 8-8 of FIG. 3 with components such as the chain conveyors omitted in the interest of clarity;

FIG. 9 is a modified sectional view of the apparatus taken along line 99 of FIG. 1 with one semicylindrical half section of the outer housing structure laterally displaced to an inoperative position;

FIG. 10 is a plan view of two abutting semi-cylindrical housing half sections equipped with water spray nozzles;

FIG. 11 is a view in side elevation taken along line 11-11 of FIG. 10;

FIG. 12 is a modified sectional view taken along line 1212 of FIG. 10 showing one of the semicylindrical sections equipped with water nozzles displaced laterally to an inoperative position;

FIG. 13 is a view in side elevation of a housing section equipped with draft inducers;

FIG. 14 is a sectional view taken along line 14-14 of FIG. 13;

FIG. 15 is a view in side elevation of a housing section equipped with heating elements for retarding the cooling rate of rod rings;

FIG. 16 is a sectional view taken along line 16-16 of FIG. 15;

FIG. 17 is a side elevational view similar to FIG. 2 showing an outer housing structure which includes in sequence the combination of air cooling, heating and Water quenching units;

FIG. 18 is a partial view in side elevation of an alternate embodiment of the invention wherein the delivery end of tubular arm member is supported by the coil collecting apparatus which is shown in section;

FIG. 19 is a view similar to FIG. 18 showing the delivery end of the tubular arm temporarily supported by the separator plate when the coil collecting mechanism is lowered to permit coil discharge;

FIG. is a sectional view taken along line 20-20 of FIG. 19;

FIGS. 21-23 illustrate the operational sequence the shear mechanism;

FIG. 24 is a sectional view taken along line 2424 of FIG. 1; and

FIG. is a sectional view taken along line 2525 0 FIG. 24.

GENERAL DESCRIPTION OF THE INVENTION Referring initially to FIGS. 1 and 2 wherein are best shown general features of one embodiment of the invention, the apparatus generally indicated by the reference numeral 12 comprises a laying head 14 having an arm member 16 extending horizontally therefrom. As will hereinafter be described in greater detail, the arm member 16 visible where the surrounding housing has been cutaway is supported at the rod receiving end 13 by laying head 14 and extends outwardly therefrom in cantilever fashion to terminate in an unsupported rod delivery end generally indicated by the reference numeral 18. The arm 16 is comprised basically of an elongated tubular wall 20 perforated along its entire length as indicated typically at 22. Wall 20 defines an inner longitudinal passageway 24 (see FIGS. 69) extending axially therethrough. It should be understood at this point that the support of arm member 16 in cantilever fashion is not a strict requisite. For example, under certain circumstances where the length of the arm precludes such an arrangement, the arm may be supported at both the rod receiving end 13 and the rod delivery end 18. This alternate construction is illustrated in FIGS. 18-20 and will presently be described in greater detail.

During operation of the mill, hot rolled steel rod emerges from the final finishing stand of the mill (not shown) and is carried by delivery pipe 32 to a suitably shaped laying pipe 34 rotatably supported within laying head 14. The delivery pipe may be additionally equipped with water cooling means to reduce the rod temperature somewhat prior to its entry into the laying pipe. However, it is to be understood that the rod will always enter the apparatus at a temperature above that at which transformation commences. The laying head operates to rotate laying pipe 34, thereby forming the incoming rod into a continuous series of rings indicated typically in FIGS. 1 and 2 by the reference-numeral 36. The rotational speed of the discharge end of the laying pipe is timed to the linear delivery speed of the rod so that the rod as it leaves the pipe is stationary in space. As each successive ring 36 is formed and axially deposited on arm member 16, it is immediately picked up and carried by

parallel chain conveyors

38 and 40. The chain conveyors run continuously from rod receiving end 13 to rod delivery end 18 and operate to move the rod rings along the length of the arm. This movement has the added effect of creating a predetermined spacing between each suc- :essive ring 36 as shown in FIGS. 1 and 2. The space between adjacent rings has been exaggerated slightly in FIGS. 1 and 2 for illustrative purposes. Arm 16 is further provided with suitably positioned staggered, overlapping rub rails 26 which cooperate with the

chain conveyors

58 and 40 to prevent the higher temperature rod rings from sagging into contact with tubular wall 20. It can :herefore be seen that the rotating laying pipe 34, elongated arm 16 and

chain conveyors

38 and 40 cooperatein arranging the rod in a continuous series of closely spaced,

concentrically aligned rings 36.

In the embodiment of the invention shown in FIGS. 1 and 2, arm member 16 is surrounded along substantially its entire length by an outer tubular housing structure 44 made up of individual semicylindrical housing half sections indicated typically by the reference numeral 46. When arranged as shown in FIGS. 1 and 2, the housing half sections 46 cooperate with the tubular wall 20 of arm member 16 to form an annular passageway 48 through which the rod rings move towards rod delivery end 18. As can be best seen in FIG. 2, a conventional blower 50 is suitably positioned beneath laying head 14 and connected by an air duct 52 and passageways within the laying head to the inner passageway 24 extending axially through the tubular wall 20 of arm member 16. When the blower is operated, a continuous flow of cooling air is forced into arm member 16. The cooling air fills passageway 24 before radially escaping through perforations 22 into annular passageway 48 where it ultimately contacts the exposed surfaces of the spaced rod rings 36 being carried along the length of arm 16 by

parallel chain conveyors

38 and 40. It should, .of course, be understood that gaseous coolants other than air such as steam, flue gas, etc. could be applied to the rod surfaces in substantially the same way.

By radially passing pressurized coolant through perforations 22, a uniform application to the exposed rod surfaces is assured around the full circumference of arm member 16. Thus, the rod rings are not dependent upon natural convection for cooling, afactor of considerable importance in view of the fact that natural convection would result in the upper halves of the rod rings being exposed to an upward flow of air which had already been heated by the lower half of the rod rings.

Each housing half section 46 is further provided with a plurality of suitably positioned exhaust dampers indicated typically by the reference numeral 54. These dampers may be individually adjusted to provide zone control for the volume of air flowing through perforations 22. The term zone control may be explained as follows: the volume of air flowing radially through perforations 22 will depend primarily on the volume of air being exhausted from annular passageway 48. If passageway 48 were to be sealed off entirely, a pressure would soon develop which would prevent further radial air flow from the interior 24 of arm member 16. By providing exhaust dampers 54 which may be opened to any desired adjustment, a relatively direct radial path is provided from the interior of arm member 16 through perforations 22 in wall20 and the tubular housing structure 44. This direct radial path will facilitate air flow through any of the perforations 22 in the vicinity or zone of a particular damper. Thus, the term zone control" is used to describe the effect realized from individually adjusting each exhaust damper 54 to in turn provide maximum control over the cooling rate of rod rings 36 as they are advanced continuously by the

conveyors

38 and 40. As the cooled rod rings arrive at the delivery end 18 of cantilevered arm 16, they are guided downwardly through an angle of approximately 90 by an appropriate means such as a guide frame 57 comprised of curved guide member 56. The rings are finally deposited on a conventional coil gathering device 58 where they are collected into a relatively concentrated coil.

Having thus generally described one embodiment of the apparatus as illustrated in FIGS. 1 and 2, it should now be apparent to one skilled in the art that the rod is received directly from the final finishing stand of the mill and formed by the rotating laying pipe 34 into a continuous series of relatively closely spaced rings. The rings are axially deposited on the rod receiving end 13 of arm member 16 and moved toward the delivery end 18 by

chain conveyors

38 and 40. Depending on the speed at which the'chain conveyors are operated, a predetermined spacing will be produced between successive rod rings 36 being formed by rotating laying pipe 34. In the embodiment shown in FIGS. 1 and 2, cooling air is introduced into the interior of arm member 16 by blower 50. The air then flows radially outward through perforations 22 in tubular wall 20 to flow over the exposed surfaces of rod rings 36 to remove heat therefrom. The flow of air passing radially through perforations 22 will be controlled by the particular setting of exhaust dampers 54 on each semicylindrical housing half section 46. Thus it can be seen that by properly adjusting both the operational speed of

chain conveyors

38 and 40 and the setting of exhaust dampers 54, the above-mentioned McLean-Easter process can be practiced with the present invention by uniformly cooling the rod rings at a predetermined controlled rate in order to impart desired metallurgical properties to the rod over its entire length.

In the more detailed description to be hereinafter presented, it will become apparent that the invention is not restricted to the particular embodiments illustrated in FIGS. 1 and 2. For example, under certain conditions it may be desirable to operate without tubular housing structure 44. Moreover, the individual semicylindrical sections which comprise housing structure 44 may be modified to achieve varying results such as water quenching or cooling retardation (commonly referred to as soaking). In addition, where the conditions require that arm member 16 be extended beyond that which is practical for a cantilevered construction, rod delivery end 18 may be supported by a modified coil forming apparatus. With this general description in mind, a more detailed description of the invention will now be provided with the aid of the remaining drawings.

DETAILED DESCRIPTION OF ARM MEMBER 16 AND LAYING HEAD 14 In FIGS. 1 and 2, arm member 16 is supported at the rod receiving end 13 in a nonrotating cantilever fashion by laying head 14. In FIGS. 3-8, the tubular housing structure 44 which is part of the apparatus as shown in FIGS. 1-2 has been removed to better illustrate arm member 16 and related parts, and, in addition, to depict an alternate embodiment of the invention wherein gaseous coolant under pressure is allowed to escape radially from the interior of arm member 16 through perforations 22 and to thereafter mix freely with the surrounding atmosphere.

Arm member 16 will now be described in greater detail with particular reference of FIGS. 3, 5 and 8. As stated in the general description, arm member 16 is comprised basically of an elongated tubular wall 20 which defines an inner axial passageway 24. The arm member terminates at one end in a mounting head generally indicated by the reference letter A which is adapted to be connected to the laying head 14 in a manner presently to be described. The other end of arm 16, which is referred to as the rod delivery end 18, is provided with arcuate guide tracks 56 suitably spaced and interconnected to provide a downwardly curving guide frame 57 over which the cooled rod rings may readily slide onto an underlying conventional coil forming device 58. The length of arm 16 may of course be varied to accommodate variables such as the delivery speed of the mill, type and size of product being rolled, etc.

As briefly mentioned in the general description, two

continuous chain conveyors

38 and 40 are located on arm member 16 to provide a means for moving rod rings formed by laying head 14 over the length of the arm towards rod delivery end 18 where they are eventually carried by guide frame 57 onto the underlying coil forming device 58. The chain guides run between idler sprockets 66 positioned adjacent rod delivery end 18 and driven sprockets 68 near the mounting head A. As can be best seen in FIGS. 7 and 8, the driven sprockets 68 are fixed to a common transverse shaft 70 suitably journaled for rotation between bearings 72 which are in turn attached by angular brackets 73 to the interior of tubular wall 20. A drive connection is provided between shaft 70 and a gear reducer 74 mounted on an intermediate shelf 76 by means of a third sprocket 78 connected to a sprocket on the output shaft 80 of gear reducer 74 by an intermediate drive chain 82. Gear reducer 74 operates through the aforementioned arrangement to drive sprockets 68 in a counterclockwise direction as viewed in FIGS. 2 and 5. The means for driving gear reducer 74 will be presently described in connection with the description of laying head 14.

The idler sprockets 66 which are located adjacent rod delivery end 18 are rotatably mounted on a common transverse shaft 84. Shaft 84 is in turn supported by spaced link members 86 pivotally connected at their lower ends as at 88 to brackets 90 which are fixed to a bafile plate 91. Baflle plate 91 seals off one end of the passageway 24 running axially through arm member 16. Links 86 are interconnected by intermediate web members 92 to which are attached rods 94. Rods 94 pass through baffle plate 91 and are constantly urged in a direction away from mounting head A by compressed coil springs 96. With this arrangement, the

chain conveyors

38 and 40 are maintained taut.

As can be best seen in FIGS. 6 and 7, the upper strands of both

chain conveyors

38 and 40 move longitudinally along cantilevered arm member 16 in stepped depressions 98 which extend from the driven sprockets 68 to the idler sprockets 66. The base of each depression is provided with replaceable longitudinal wear plates 100 which provide additional support for the upper conveyor strands as they travel along the arm. Similarly, the lower strands of the chain conveyors are supported in their travel from the idler sprockets 66 back to the driven sprockets 68 by a second set of replaceable wear plates 102 supported by angular brackets 104 running along the interior of passageway 24. As previously mentioned, while moving along the length of arm 16 under the influence of

chain conveyors

38 and 40, the rod rings are radially supported and held away from tubular wall 20 by rub rails 26. The rub rails are angularly disposed and arranged along the outer surface of arm 16 at spaced overlapping intervals to avoid the creation of cold spots on the rod caused by prolonged metal to metal contact at any one location. The rub rails may be fabricated of any suitable material such as bronze in order to avoid marking the surfaces of the rod rings.

Referring now to FIG. 5 wherein arm member 16 is shown prior to its connection to laying head 14, it can be seen that the end referred to as mounting head A is provided with a relatively constant diameter section 108 tapering gradually as at 110 to finally terminate in a reduced diameter end section 112. A relatively large diameter bearing assembly 114 surrounds constant diameter section 108 at a point spaced inwardly from another smaller diameter bearing assembly 116 located on reduced diameter end section 112 near the tip of the arm. A rotatable drive shaft 118 extends axially through mounting head A from gear reducer 74 to a spur gear 120 located at the outermost tip of the arm. Another fixed gear 122 is mounted on mounting head A immediately to the rear of bearing assembly 116.

When attaching arm 16 to laying head 14, mounting head A is inserted and supported by inner components of the laying head as shown in FIG. 4. Laying head 14 is comprised basically of an outer stationary housing structure B containing an intermediate laying head rotor assembly C to which is attached the curved laying pipe 34. Mounting head A is axially positioned and supported within the intermediate laying head rotor assembly C, the former being held in a nonrotatable relationship to the latter by means of a planetary gear arrangement D. Thus it can be seen that when arm 16 is attached to laying head 14, mounting head A is axially supported within an intermediate laying head rotor assembly C which is 1n turn rotatably contained within the stationary housing structure B.

With this brief introductory reference to the combination of laying head subassemblies (B, C, D) which cooperate with mounting head A in supporting the rod receiving end 13 of arm member 16, a more detailed description of each subassembly willnow be provided. The laying head rotor assembly C is comprised of a rotor element 124 rotatably mounted within the stationary outer housing structure B by means of two relatively large diameter bearing assemblies 126a and 12Gb. Curved laying pipe 34 is attached to the laying head rotor 124 and rotates with it relative to housing structure B. P ogressing from right to left as viewed in FIG. 4, laying pipe 34 may be described as having a straight entry section 128 concentrically aligned with the axis of rotation of laying head rotor 124. Straight entry section 128 is contained within and fixed at its entering end to a larger diameter sleeve 130 which is flared out as at 132. Sleeve [30 rotates with laying pipe 34. From straight entry section 128, laying pipe 34 curves outwardly through the flared portion 132 of sleeve 130 and the center portion of rotor 124. The laying pipe then passes through passageway 134 in laying head rotor 124 adjacent bearing assembly 126a. As can be best seen in FIG. 8 which is a sec- ;ional view taken through arm 16 looking towards laying head 14, the end portion of guide pipe 34 turns as at [36 and then follows a semicircular path spaced from and extending around tubular wall 20 of cantilever arm [6. With this construction, rod 30 will pass through the straight entry section 128 and thereafter be guided by laying pipe 34 around tubular wall 20 where it will finally emergeas shown in FIG. 8. Laying pipe 34 is addi- :ionally braced at a point adjacent its delivery end by in L-shaped bracket 138 which is secured as at 140 to the aying head rotor 124.

Laying head rotor assembly C is driven by means of 1 circumferentially disposed ring gear 142 which meshes with a drive gear 144 keyed to a relatively short shaft [46. Shaft 146 is journaled for rotation between bearing issemblies 148 and connected by means of coupling 150 :o the output shaft of a variable speed drive motor 152.

As shown in FIG. 4, the mounting head A of arm nember 16 is axially inserted and supported within layng head rotor assembly C. More particularly, the outer races of bearing

assemblies

114 and 116 on mounting lead A are fixed within the axially spaced bores 154 and [56 which are integrally formed as parts of the laying lead rotor 124. As diagrammatically illustrated in FIG. 5, when arm member 16 is supported in a cantilever Fashion (as shown in FIGS. 1-17), its weight is, con- :entrated at an approximate point indicated by the force IectorF This downward force is counterbalanced by in upward force F exerted through bearing assembly [14 and a downward force F exerted through bearing issembly 116. This results in the arm 16 being supported n cantilever fashion while still permitting relative rotaion between it and the laying head rotor assembly C which is in turn rotatably contained by bearing assemblies [26a and 126b within the stationary housing structure )f laying head 14.

When supported in cantilever fashion, arm member [6 will have a tendency to rotate with laying head rotor issembly C due to the friction constantly being de- Ieloped between the inner and outer races of bearing as- :

emblies

114 and 116. A planetary gear arrangement D s used to overcome this tendency, thereby maintaining arm 16 is a nonrotating position. As can be best seen n FIG. 4, planetary gear arrangement D is comprised )f a shaft member 158 journaled for rotation as a part of laying head rotor 124 between bearings 160. A spur gear [62 is keyed to one end of shaft 158 and is positioned to mesh with gear 122 which is fixed to the reduced diameter end section 112 of mounting head A immediately to adjacent bearing assembly 116. The other end of shaft 158 is provided with an identical spur gear 164 which meshes with an adjacent fixed ring gear 166. Gear 166 is fixed to an internal sleeve 168 which is a nonrotating integral portion of housing structure B. Gears 122 and 166 are the same size and have the same pitch and number of teeth. The same relationship applies to gears 162 and 164. Thus it can be seen that as laying head rotor assembly C rotates within housing structure B, under the driving force of gear 144 acting on ring gear 142, gear 164 will rotate as a planetary gear around fixed gear 166 as gear 162 rotates in a similar manner around gear 122. Since gear 166 is part of housing structure B and does not rotate, gear 122 which is part of mounting head assembly A will also be maintained in a nonrotating relationship, thereby preventing rotation of arm 16. In this manner, laying pipe 34 will spin around nonrotating arm 16. During operation of the apparatus, the rotational speed of the laying head rotor assembly C and the associated laying pipe 34 is adjusted so that the peripheral speed of the discharge end of the laying pipe is equal to that of the rods linear speed as it issues from the final finishing stand. This results in the rod being formed into a continuous series of stationary adjacent rings 36.

Referring now to FIG. 3 which clearly shows the position of laying pipe 34 overlying arm 16, it can be seen that each successive rod ring that is formed by a revolution of laying head motor assembly C will be deposited on

chain conveyors

38 and 40. As previously pointed out, the upper strands of each chain conveyor are continuously running in a direction away from laying head 14 and towards rod delivery end 18. Thus as each rod ring is formed, it is immediately picked up by

chain conveyors

38 and 40 and carried along arm 16 towards rod delivery end 18. By properly adjusting the speed at which the chain conveyors are running in relation to the rotational speed of laying head rotor assembly C, a predetermined spacing can be provided between the successive rod rings being formed, thereby insuring maximum exposure of rod surface which, as will hereinafter be discussed in more detail, is important to the attainment of a truly uniform cooling operation.

The means provided for driving

chain conveyors

38 and 40 through gear reducer 74 will now be described with, particular reference to FIG. 4. A variable speed motor 170 of conventional design is connected through an intermediate coupling 172 to a relatively short shaft member 174 which is journaled for rotation between bearing assemblies 176 carried by housing structure B. A gear 178 fixed to shaft 174 meshes with a second gear 180 mounted on one end of a nonuniform diameter tubular sleeve 182 which surrounds the inner sleeve 130 attached to guide pipe 124. Sleeve 182 is journaled for rotation between bearing assemblies 184 carried by the fixed internal sleeve 168 which is an integral portion of housing structure B. Sleeve 182 is additionally provided at its other end with another gear member 186 which meshes with an adjacent gear 188 mounted on shaft 190. Shaft 190 is journaled for rotation between bearing assemblies 192 which are carried by the rotatable laying head rotor 124. A second gear member 194 is mounted adjacent the other end of shaft 190 to mesh with spur gear 120 fixed to the end of shaft 118. As previously discussed, shaft 118 extends axially through mounting head assembly A and is connected to gear reducer 74. With this arrangement, it can be seen that although laying head rotor 124 rotates relative to both housing structure B and mounting head assembly A, power will continuously be supplied to gear reducer 74 through the above-described mechanical arrangement which provides a direct drive connection between motor 170 and shaft 118. Since both

motors

170 and 152 are of the variable speed type, the relative operational speeds of laying head rotor assembly C and

chain conveyors

38 and 40 may be readily adjusted to achieve any desired predetermined spacing between rod rings 36 being axially deposited on arm 16. The position of gear 194 in laying head rotor 124 is angularly removed from pipe 34 so that these two parts as viewed in FIG. 4 are side by side in noninterfering relation.

As previously mentioned with reference to FIG. 2, a blower 50 is located beneath laying head 14 and connected to the interior thereof by means of an intermediate air duct 52. When blower 50 is operated, a continuous flow of cooling air is forced into a segregated chamber 196 of generally annular shape located between the interior of housing structure B and laying head rotor assembly C. As diagrammatically indicated by the dotted arrows in FIG. 4, the air then flows through connecting

intermediate passages

198 and 200 in both the laying head rotor 124 and the stationary mounting head A to enter the interior passageway 24 of cantilevered arm 16. The air is prevented from escaping from chamber 196 other than through

passageways

198 and 200 by a plurality of noncontacting labyrinth type air barriers indicated typically by the reference numeral 202.

DESCRIPTION OF HOUSING STRUCTURE 44 Having thus provided a description of laying head 14, arm member 16 and the various components associated therewith, attention will now be focused on housing structure 44. In the embodiment shown in FIGS. 1, 2 and 9-17, arm member 16 is shown enclosed along substantially its entire length by a housing structure 44 comprised of a plurality of semicylindrical half sections 46. The half sections are arranged on either side of arm 16 and when brought together as shown, they cooperate with the arm in defining an annular passageway 48 through which rod rings 36 are carried from the rod receiving end 13 of the arm adjacent laying head 14 towards rod delivery end 18 by the

chain conveyors

38 and 40.

As can be best seen by comparing FIGS. 1, 2 and 9, housing sections 46 are comprised basically of semicylindrical wall members 204 having vertically disposed carriage members 206 attached as by welding to their outer surfaces. The carriage members are in turn provided with rollers 208 which are arranged to roll along suitably spaced underlying tracks 210. The tracks are located on the mill floor and run in a direction transverse to the longitudinal axis of arm 16. Stops 211 (see FIG. 9) on the innermost ends of the tracks limit the extent to which the housing half sections 46 may be advanced and in this manner control their final positioning by operating personnel. When each half section is fully advanced, the sections 46 will abut at the top and bottom.

In the housing construction shown in FIGS. 1, 2 and 9, each half section 46 is further provided with a plurality of aligned upper and lower exhaust damper assemblies 54. Each damper assembly is comprised basically of a short duct 212 leading from an opening in the semicylindrical wall member 204 to the surrounding atmosphere. A damper plate 216 which is manually adjusted by a hand wheel 218 is positioned within each duct 54 and depending on its setting will control the flow of air being exhausted from annular passageway 48. As shown in FIG. 9, the upper exhaust dampers are closed and the lower dampers open.

As mentioned earlier, the above-described damper arrangement provides a means for controlling the flow rate of air passing radially through the perforations 22 in arm 16. More particularly, by closing an exhaust damper 54, the outward flow of air from annular passageway 48 in the zone of this damper will be retarded with a corresponding retardation in the flow rate of air passing through the perforations 22 in the same zone. In this manner, a greater degree of control is attainable over the temperature reduction rate of rod rings 36 being carried along arm member 16 by

chain conveyors

38 and 40.

An alternate embodiment of the basic housing section shown in FIGS. 1, 2 and 9 is disclosed in FIGS. 13 and 14 wherein draft inducing means in the form of exhaust fans 220 are connected to each half section. This housing modification is particularly useful where arm 16 is of considerable length and difiiculties are encountered in maintaining an adequate air flow through the perforations 22 near its rod delivery end 18. This alternate embodiment of the housing half section which shall be referred to by the reference numeral 46a is comprised of two

semicylindrical wall members

222 and 224 spaced to define an arcuate chamber 226 closed at both ends. Each arcuate chamber 226 is in communication at its upper end through an intermediate duct 227 with an exhaust fan 220. Operation of exhaust fan 220 will create a nega tive pressure in arcuate chamber 226. Chamber 226 is connected to the annular passageway 48 formed between housing 46a and the tubular wall 20 of arm 16 by openings 228 over which are positioned valve assemblies 230. Each valve assembly is comprised of a pivotal plate member 232 seated over the underlying openings 228 and connected to a manually adjustable hand wheel 234. As shown in FIG. 14, the upper valve assemblies of two abutting half sections 46a have been adjusted to the open position and the lower valve assemblies closed. With this arrangement, it can be seen that by properly adjusting valve assemblies 234, a suitable draft can be induced in annular passageway 48, thereby promoting an outward radial flow of cooling air from inner axial chamber 24 through perforations 22 in tubular wall 20 of arm 16. In this manner, a flow of cooling air past the rod rings 36 being carried by the arm can be assured even at points far removed from the fan 50 located beneath laying head 14.

To this point, the description of the housing structure 44 which surrounds arm member 16 has related to

semicylindrical half sections

46 and 46a. These half sections deal primarily with the control of cooling air flow past rod rings 36 as they are carried by the

chain conveyors

38 and 40 along the length of arm member 16. However, the housing construction is not limited solely to the forms thus far described and may be modified further to achieve varying results, depending on the requirements of a particular mill installation. An example of such an additional modification is illustrated in FIGS. 10-12 where two abutting semicylindrical housing half sections generally indicated by the reference numeral 46b have been provided with means for applying a water spray to the rod rings 36 being carried along arm 16. As shown in these drawings, each housing half section 46b is exteriorly provided with two vertical stand pipes 236 which are suitably connected by a lower intermediate pipe and a flexible hose 238 to water headers 240 running under the mill floor. The stand pipes 236 are further connected by means of control valves 242 and short flexible hoses indicated typically by the reference numeral 244 to water spray nozzles 246 extending through the Wall of the housing section. A control valve 248 at the lower end of each stand pipe may be adjusted to close off the entire bank of water spray nozzles being fed by a particular stand pipe.

As is best illustrated by the left-hand side of FIG. 12, when a housing half section 46b is advanced along tracks 210 to its operative position adjacent arm 16, nozzles 246 will cooperate to produce a fine water spray which depending on the particular setting of valves 242, will quench the rod at any predetermined rate. The water will flow over the surface of the spaced rod rings 36 and then pass downwardly as indicated diagrammatically by the dotted arrows into a centrally located flume 249. This type of installation provides a means for quickly reducing the temperature of the rod rings where such treatment is required to produce desired metallurgical properties in the rod. I

In addition to reducing the temperature of the rod either by the use of cOOling air or by the application of a water spray, it may be desirable under certain circumstances to hold the rod temperature at a given level for a predetermined period of time. When such is the case, the housing structure 44' surrounding cantilever arm member 16 may be further modified as illustrated by the embodiments shown in FIGS. 15 and 16. In this particular modification, the semicylindrical housing sections which will hereinafter be referred to by the reference numeral 460 are provided internally with heating elements 250. The heating elements are connected to an external source of power by means of insulated flexible wire leads 252 and when energized generate radiant heat which serves to retard the cooling rate of rod rings 36 being carried by arm 16. In this manner, the temperature of the rod may be held at or near a predetermined temperature for a given period of time prior to being cooled further either by a flow of cooling air or an application of water as described in connection with the other housing half section embodiments previously discussed.

As a precautionary measure, housing structure 44 may also include two generally semicylindrical cobble guard half sections 231a and 231k (see FIG. 24) arranged to I surround arm member 16 at the area adjacent the circular path traveled by the delivery end of the guide pipe 34. When the rotational speed of guide pipe 34 is properly adjusted to equal that of the rod delivery speed of the mill, the rod will be laid properly on arm member 16 and there will be no need for surrounding cobble guard. However, should the rotational speed of the guide pipe and the delivery speed of the mill be improperly synchronized, as may be the case when the mill is initially being put into operation, then the guard sections 231a and 231b will serve to contain the rod and prevent injury to operating personnel.

It should also be noted that as a length of rod enters the apparatus from the rod mill, its leading end may emerge from laying pipe at any point relative to the circumference of supporting arm 16. If the rod emerges from the laying pipe as the pipe is making an upward counterclockwise sweep (as shown in FIG. 24 from approximately 135 to the leading rod end will lie on the arm without dangling. However, this ideal condition cannot always be assured. For example, if the rod emerges from the'laying pipe as the pipe rotates in a counterclockwise direction from 0 to approximately 135, the leading rod end may slip from the arm and fall until contacted by one or both of the surrounding cobble guard half sections 231a and 231b. When this occurs, the dangling rod section should preferably be cut in order to avoid any possibility of subsequent snagging as the rod iscarried through the apparatus by the chain conveyors 38 and 40'.

To this end, piston actuated shears 233a and 233b are mounted on the cobble guards 231a and 23112. As can be best seen in FIG. 25, shear 233a includes a C-shaped frame 235 having a fixed blade 237 which cooperates with a movable blade '239 to perform a cutting operation. Movable blade 239 is mounted on the end of a piston rod 241 reciprocally contained within a cylinder 243 which may be of the hydraulically or pneumatically actuated type. A control switch 245 having an actuating finger 251 extending across the jaw of the shear serves as a means of triggering the shear. It is to be understood that although shear 233b is positioned on cobble guard 23112 at a different point in relation to' supporting arm 16, its

construction is identical to that of shear 233a.

With this arrangement, if rod should emerge from laying pipe 34 in the angular range between 225 and 135, a portion 253 will dangle from arm 16 as shown in FIG. 24. As the rod advances into the cooling apparatus, rod portion 253 will enter the paws of shear 233a and as shown diagrammatically in FIG. 25 will eventually ac luate switch 245 by striking finger 251. The shear will then operate to sever the dangling rod portion 253, causing it to slide downwardly through an opening 257 between the lower abutting edges of cobble guards 231a and 231b into a crop pit 259.

Should rod emerge from guide pipe 34 in the range between 0 and 270, the dangling portion will be of greater length, as for example that shown dotted in FIG. 24 at 253a. Under these conditions, both shears 233a and 233b will be actuated to cut the dangling portion into two pieces in order to facilitate dumping through opening 257 into crop pit 259.

In view of the above, it can therefore be seen that regardless of the point at which rod begins to emerge from guide pipe 34, the possibility of a dangling portion becoming snagged in the apparatus will be obviated by the operation of one or both the shears 233a and 233b.

NONCANTILEVERED ARM CONSTRUCTION As mentioned earlier in the description, where a cantilevered construction is not practical because of the extended length of arm member 16, the arm may be additionally supported at the rod delivery end 18 by a slightly modified coil forming apparatus. One such arrangement is disclosed in FIGS. 18-23 wherein the downwardly disposed guide frame 57 at the delivery end 18 of arm 16 is provided with depending

noses

254 and 255. Nose 254 is suitably positioned to be engaged by the core 256 of a modified coil forming apparatus 258. The core 256 is supported between roller guides 260 for vertical movement between a raised position contacting note 254 as shown in FIG. 18 and a lowered position as shown in FIG. 19. This core may be vertically displaced by any conventional means such as the hydraulic ram 262 shown in the drawings.

When the core 256 of cooling apparatus 258 is in a raised position as illustrated in FIG. 18, it will support the delivery end 18 of arm 16 by virtue of its contact with nose 254. At this point, cooled rod rings 36 will be guided downwardly by guide frame 57 to accumulate in coil form as at 264 in the annular chamber 265 formed between core 256 and the surrounding horse-shoe shaped wall 266 of coil forming apparatus 258. At this stage, core 256 will be locked in the raised position by a linkage assembly 268.

When a suflicient weight of coiled rod rings has been deposited within chamber 265, a separator plate 270 is advancedfrom its retracted position shown in FIG. 18 to a position inserted between guide frame 57 and coil forming apparatus 258. Separator plate 270 may be advanced and subsequently retracted by any conventional means such as the hydraulic ram 272 shown in the drawings. When separator plate 270 is advanced to the inserted position shown in FIG. 19, two basic functions are fulfilled. First, the deposit of rod rings 36 into chamber 265 is temporarily interrupted, causing subsequent rings to begin accumulating on the top surface of the plate as shown in FIG. 19. Moreover, as can be best seen in FIG. 20, the forward edge of separator plate 270 is cut away as at 271. The rod portion 269 intercepted by plate 270 'will be caught within cut away portion 271 and carried forward to an area adjacent shear mechanism 273 when the separator plate is advanced. Shear mechanism 273 is comprised basically of a cutter 275 and a barbed spear 276 which may advance and retract by means of a cylinder 277. Once the separator plate 270 is in position between guide frame 57 and coil forming apparatus 258, spear 276 is then advance as shown in FIG. 21 until the barb apparatus 258 to its surrounding wall 266. More particularly, as the separator plate is advanced it will pass beneath the shorter length depending nose 255. The plate will be guided and carried by rollers 274 on the outer wall 266 of coil forming apparatus 258 and will also avoid contact with depending nose 254 due to the cut away section 271 in its forward edge. Following advancement of the separator plate to an operative position as shown in FIG. 19, core 256 is dropped. When this occursjthe rod delivery end 18 of arm 16 will also drop slightly until nose 255 comes to rest on the upper surface of separator plate 270. This has the effect of transferring the support of arm 16 from core 256 to the separator plate, which is in turn supported by rollers 274 on wall 266. A pusher arm 280 is then advanced by a horizontally disposed ram 282 to push the collected coil 284 out through the open side of horseshoe shaped wall 266 (compare FIGS. 19 and 20). With coil 284 ejected from coil forming apparatus 258, the pusher arm 280 is withdrawn, core 256 again elevated to contact nose 254 (causing nose 255 to be lifted off separator plate 270 and separator plate 270 withdrawn, all in this order. The rod rings which had previously accumulated on the top surface of the separator plate as at 288 drops into the coiling apparatus as soon as the separator plate is withdrawn and the coil cycle is again repeated. With this arrangement, individual coils are formed and removed from the apparatus whilemaintaining a continuous uninterrupted support under the rod delivery end 18 of arm 16.

OPERATIONAL DESCRIPTION OF THE APPARATUS In view of the above, it should. now be apparent to one skilled in the art that the basic form of the apparatus as shown in FIG. 3 comprises an elongated arm 16 extending horizontally from a laying head 14 which is positioned to receive hot rolled steel rod 30 issuing directly from the final finishing stand of the mill. The arm may also be supported at the rod delivery end 18 as shown in FIGS. 18-23. Although the rod may-have been cooled to some extent by conventional means such as water spray nozzles in the delivery pipes, its temperature when it enters the apparatus will still be above that at which metallurgical properties are fixed. The laying head contains a laying pipe 34 which'rotates at a speed adjusted to the rod delivery speedto form the incoming rod into a continuous series of concentrically aligned rings 36. The rings are deposited on arm 16 at its rod receiving end 13 and thereafter are carried by

chain conveyors

38 and 40 towards the rod delivery end 18. By regulating the operational speed of the chain conveyors in relation to the speed at which the laying pipe is rotating, a predetermined spacing is provided between each successive rod ring being deposited on the arm. Thus it can be seen that the rod rings are placed in a controlled closely spaced concentrically aligned arrangement, thereby achieving maximum exposure of surface area.

With the basic form of the invention as described above, cooling will take place as a result of conduction, radiation and natural convention. Localized heat transfer due to conduction will be kept to a minimum because each ring is supported at only two points by the

chain conveyors

38 and 40, and at three other points by the radially disposed rub rails. The rub rails are placed in an angularly disposed overlapping arrangement to avoid contacting the rod at any given point for an extended period of time.

Cooling by radiation will be substantially uniform and accelerated over the entire length of the rod due to the spaced arrangement of the individual rod rings and the radial spacing from the wall 20 of the axially extending arm member 16. Finally, cooling by natural convention will be promoted and to a considerable extent controlled by the number and distribution of perforations 22 which connect passageway 24 to the surrounding atmosphere. All of these factors will combine to provide uniform cooling of successive rings in a controlled manner to achieve the objectives of the McLean-Easter process.

Beginning with this basic construction, alternate de vices may be employed to vary the results being obtained. For example, arm member 16 may be enclosed within a tubular housing structure 44 as shown in FIGS. 1 and 2. This arrangement should preferably 'be coupled with use of means such as a blower 50 for forcing air into passageway 24. With this embodiment, cooling due to conduction would be at a minimum and radiational cooling would be substantially uniform over the entire length of the rod. However, closer control over the cooling due to convection would be provided by virtue of the damper assemblies 54 which are individually adjustable to regulate the flow of air passing over the exposed surfaces of the rod.

As shown in FIGS. 10-17, the housing structure 44 may be modified extensively by simply combining different types of semicylindrical housing sections. FIG. 17 is an illustration of one such modification wherein the rod is initially air cooled while passing through housing sections 46, then held at a relatively constant temperature by being exposed to heating elements 250 (see FIG. 16) contained within housing section 46c, and finally water quenched by a battery of water spray nozzles 246 mounted within sections 46b. It should now be obvious to one skilled in the art that many different combinations are possible with this equipment since the various housing half sections are fully interchangeable. Thus a rod producer may modify the housing construction to suit the particular needs of a current rolling operation and thereby attain increased flexibility while still maintaining close control over the cooling rate of the rod.

I claim:

1. Apparatus for cooling hot rolled steel rod at a controlled rate in direct sequence with a rolling mill comprising: means for forming hot rolled rod issuing from said mill into a continuous series of rings, means including spaced open supports for temporarily supporting and advancing said rings in a spaced concentrically aligned arrangement abouta common axis with a major portion of the rod surface exposed, and means for directing a fluid cooling medium through said supports and said rings at least along a substantial length of said supports in such a manner as to control the rate of heat loss from each of said moving concentrically aligned rings during the temporary arrangement thereof about said common axis to achieve a predetermined uniform metallurgical structure progressively over the entire length of said rod.

2. The apparatus as set forth in claim 1 further characterized by means for collecting said spaced concentrically aligned rings into a relatively compact coil following the controlled cooling thereof.

3. For use with a rolling mill, apparatus for cooling hot rolled steel rod at a controlled rate comprising: laying means for forming high temperature rod being received directly from said mill into a continuous series of rings; an elongated arm member supported at one end at saidlaying means and extending outwardly therefrom to terminate in a rod delivery end, said arm member adapted with spaced supports to receive and support the rings being formed by said laying means in axial alignment thereon; means for moving said rings along the length of said arm member on said supports towards said rod delivery end; and means associated with said arm member for directing a fluid cooling medium through and between said supports and rings and at least along a substantial length of said arm in such a manner as to produce a substantially uniform rate of heat transfer per unit of rod length from said rings to the surrounding atmosphere while the rings are moving along said arm member.