U.S. patent number RE33,490 [Application Number 07/272,719] was granted by the patent office on 1990-12-18 for apparatus to mechanically stress a bolt-type fastener.
Invention is credited to Rolf H. Steinbock.
United States Patent |
RE33,490 |
Steinbock |
December 18, 1990 |
Apparatus to mechanically stress a bolt-type fastener
Abstract
A plurality of jack bolts are threadedly engaged with openings
in a flange on a fastener to stress a shank part of the fastener.
The flange can be a collar retained on a shaft by a retainer, a nut
on a threaded end of a bolt or the head portion of a bolt. The jack
bolts can be arranged in a flange on an end of the tension rod to
stress arbors against opposite sides of a roll sleeve to form a
roll assembly for use in a rolling mill.
Inventors: |
Steinbock; Rolf H. (Carnegie,
PA) |
Family
ID: |
27402504 |
Appl.
No.: |
07/272,719 |
Filed: |
November 16, 1988 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
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595402 |
Mar 30, 1984 |
|
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Reissue of: |
704967 |
Feb 27, 1985 |
04622730 |
Nov 18, 1986 |
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Current U.S.
Class: |
492/2; 403/320;
411/432; 492/7 |
Current CPC
Class: |
B21B
27/035 (20130101); B25B 29/02 (20130101); F16B
31/04 (20130101); F16D 1/033 (20130101); F16D
1/06 (20130101); F16D 1/097 (20130101); Y10T
403/589 (20150115) |
Current International
Class: |
B21B
27/02 (20060101); B25B 29/00 (20060101); B25B
29/02 (20060101); F16D 1/06 (20060101); F16D
1/097 (20060101); F16D 1/033 (20060101); F16B
31/00 (20060101); F16D 1/091 (20060101); F16D
1/02 (20060101); F16B 31/04 (20060101); F16D
001/00 (); F16D 035/00 (); B21B 013/02 () |
Field of
Search: |
;29/110,116.2,426.6,446
;403/11,12,320
;411/432,433,431,435,427,337,353,354,511,516,517,521,533,535,536,539,916,917,140
;285/396,361 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2135015 |
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Nov 1972 |
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DE |
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643329 |
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May 1928 |
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FR |
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349811 |
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Dec 1972 |
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SU |
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473545 |
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Oct 1937 |
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GB |
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510144 |
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Jul 1939 |
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GB |
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764539 |
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Dec 1956 |
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GB |
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1136280 |
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Dec 1968 |
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GB |
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2088263 |
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Jun 1982 |
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GB |
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2134613 |
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Aug 1984 |
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GB |
|
2144819 |
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Mar 1985 |
|
GB |
|
Primary Examiner: Eley; Timothy V.
Attorney, Agent or Firm: Poff; Clifford A.
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATION
This application is continuation-in-part of application Ser. No.
595,402, now abandoned, filed Mar. 30, 1984.
Claims
I claim as my invention:
1. A fastener apparatus to compress a support member against a
first member, said apparatus including an elongated shank part
extending from said first member and passed freely through an
enlarged opening in said support member, an anchor flange connected
to one end portion of said elongated shank part for support by said
first member, a stress generating flange connected to an opposite
end portion of said elongated shank part for exerting a compressive
force on said support member, said stress generating flange having
a plurality of holes at spaced-apart locations about an outer
peripheral part thereof to overlie said support member, and a
plurality of jack bolts threadedly engaged with said holes to
separately receive a torque, the jack bolts having end parts
extending from said holes to stress said elongated shank part
extending between said anchor flange and said stress generating
flange through torquing said jack bolts for applying a compressive
reaction force between said support member and said first
member.
2. The apparatus according to claim 1 wherein said support member
includes a washer having a face surface defining a preselected
hardness for preventing deformation of surfaces of said jack bolts
in contact therewith.
3. The apparatus according to claim 1 wherein said stress
generating flange includes a collar having an opening to receive a
portion of said elongated shank part, said apparatus further
including retaining means for anchoring said collar to said
elongated shank part.
4. The apparatus according to claim 3 wherein said retaining means
includes a retainer supported in a recess in said shank.
5. The apparatus according to claim 4 wherein said support member
is an anti-friction bearing.
6. The apparatus according to claim 5 wherein said retaining means
includes projection on said collar and said elongated shank part
forming a releasable bayonet connection.
7. The apparatus according to claim 1 further including a spacer
between said jack bolts and said support member.
8. The apparatus according to claim 7 wherein said spacer includes
web and flange sections for breaking and shearing .[.in the.].
.Iadd.when .Iaddend.said jack bolts are torqued to produce an
excessive load.
9. The fastener apparatus according to claim 1 wherein said support
includes a hardened washer for contact by the end parts of said
jack bolts.
10. The fastener apparatus according to claim 1 wherein said
support member includes a roll sleeve, said anchor flange and
stress generating flange include bearing chocks and said elongated
shank part includes an arbor.
11. The fastener apparatus according to claim 1 wherein said stress
generating flange comprises an enlarged head portion of a bolt.
12. The fastener apparatus according to claim 1 wherein said stress
generating flange comprising a nut member secured by threads to
said shank.
13. The fastener apparatus according to claim 1 wherein said stress
generating flange has a plurality of holes spaced about different
diameter bolt circles, and a jack bolt threadedly engaged with each
.[.hole.]. .Iadd.bolt .Iaddend.in each hole circle.
14. Apparatus to compressively support a roll sleeve between arbors
for forming a roll assembly, the combination therewith of an
elongated shank part secured to one of said arbors to extend freely
through an enlarged opening in said roll sleeve and through an
enlarged opening in the other arbor, said elongated shank being
spaced by an annular gap from said roll sleeve, a stress generating
flange secured to an end portion of said elongated shank part
extending from said other arbor, said stress generating flange
having a plurality of holes at spaced-apart locations about an
outer peripheral part thereof overlying the said other arbor, and a
plurality of jack bolts threadedly engaged with said holes to
separately receive the torque, the jack bolts having end parts
extending from said holes against said outer shank part for
applying a compressive reaction force on said roll sleeve by said
arbors through torquing of said jack bolts.
15. The apparatus according to claim 14 wherein said arbors include
annular sleeve support surfaces and an overlying conically-shaped
surface for compressively engaging said sleeve.
16. The apparatus according to claim 14 wherein said stress
generating flange comprises a nut member threadedly attached to
said elongated shank part.
17. The apparatus according to clai 16 including bearing chocks for
supporting said arbors.
18. The apparatus according to claim 14 wherein said roll sleeve is
compressed between said arbors to resist radially-applied rolling
forces on the roll sleeve perpendicular to the length of said
elongated shank. .Iadd.
19. A fastener apparatus to compress a support member, said
apparatus including an elongated shank part extending from said
support member and passed through an opening in said support
member, said shank extending portion and said support member in
said opening having a mechanical free relationship throughout the
length of said shank portion, an anchor flange connected to one end
portion of said elongated shank part for exerting a compressive
force on a first portion of said support member, a stress
generating flange connected to an opposite end portion of said
elongated shank part for exerting a compressive force on a second
portion of said support member, said stress generating flange
having a plurality of holes at spaced-apart locations about an
outer peripheral part thereof to overlie said support member, and a
plurality of jack bolts threadedly engaged with said holes to
separately receive a torque, the jack bolts having end parts
extending from said holes to stress said elongated shank part
extending between said anchor flange and said stress generating
flange through torquing said jack bolts for applying said
compressive reaction forces on said support member. .Iaddend.
.Iadd.20. The apparatus according to claim 19 wherein said
mechanical free relationship is characterized as a press fit
between said shank extending portion and said
support member. .Iaddend. .Iadd.21. The apparatus according to
claim 19 wherein said mechanical free relationship is characterized
by the absence of intermeshing threads between said shank extending
portion and said support member. .Iaddend. .Iadd.22. The apparatus
according to claim 19 wherein said mechanical free relationship is
characterized by adjacent sliding surfaces between said shank
extending portion and said support member. .Iaddend.
Description
BACKGROUND OF THE INVENTION
This invention relates to apparatus to stress a shank part of a
fastener such as a bolt, shaft, or a stud, and more particularly to
providing a plurality of jack bolts arranged at spaced-apart
locations to extend between a surface of a support and an outer
peripheral part of a flange for stressing the fastener through
torque applied to the various jack bolts. The flange can be an
integral part of the shank or the flange can be retained on the
shank by, for example, threads, any of numerous forms of a retainer
ring or a fastener. The apparatus of the present invention can be
used, for example, to clamp arbors against opposite sides of a roll
sleeve to form a roll assembly.
It is a common practice for workmen to stress a bolt by applying
torque to the bolt head to advance a threaded portion along threads
in a tapped hole or a nut member so that the shank portion of the
bolt is placed under a desired or predetermined mechanical stress.
The stress imparted to the shank portion of the bolt can be
determined by using a torque wrench to measure the torque applied
to the bolt or by using other means to measure the applied force by
a spanner wrench. The torque may be applied to the head portion of
the bolt or to the nut. A stud can be stressed in a similar way by
torque applied to a nut engaged with a threaded portion of the
stud. The present invention is designed to permit stressing of a
large fastener, e.g., a bolt or a stud, having a diameter generally
one-inch or larger. The magnitude of stress than can be applied to
a bolt, stud or similar fastener has limits of practicality,
particularly with respect to workmen. A one-inch diameter threaded
bolt made of high-strength material can be tightened by the use of
a spanner wrench to the elastic limit of the material. With coarse
threads, a stress to the elastic limit of the material requires
about 1000 ft-lb of torque, .[.i.e..]. .Iadd.e.g. .Iaddend.100
pounds of force applied by a 10 foot lever. Under ordinary
.[.condition.]. .Iadd.conditions.Iaddend., this exceeds .Iadd.both
.Iaddend.the practical length of the lever and the amount of force
a workman can deliver to the lever. Under usual conditions, a
workman using a spanner wrench cannot stress the shank of a nut and
bolt assembly that is four inches in diameter with coarse threads
to 57,000 ft-lb which is the required torque to stress the bolt to
the elastic limit of a typical material comprising the nut and
bolt. To develop torque of this magnitude, 5700 pounds of force
must be applied to a 10-foot long lever which cannot be
accomplished without employing massive machinery or special
facilities.
Hydraulically-powered devices are known in the art for stressing or
tensioning the shank portion of a fastener but such devices are
undesirable because the magnitude of force which can be developed
is restricted to available mounting space for the device. If space
is available for mounting a hydraulic tensioning device, it is
typically necessary to develop a hydraulic pressure of about 15,000
psi. Examples of such hydraulic tensioning devices can be found in
U.S. Pat. Nos. 3,835,523; 3,841,193; 3,886,707; 4,075,923 and
4,182,215.
Thermal shrinkage is a much older method for stressing a bolt. The
bolt is first heated to elongate its shank. The bolt is then
torqued to a precalculated stress and finally the bolt is allowed
to cool so that upon cooling, thermal shrinkage tensions the bolt.
Usually, this method cannot be used where the amount of stress must
be accurately controlled or precisely established. It is also
difficult to unscrew the bolt from the threaded member without
reheating the bolt.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an apparatus
for stressing a shank portion of a bolt, shaft or stud such as a
fastener by relatively simple, mechanical means by which relatively
high stress levels can be obtained with reasonable accuracy.
It is .Iadd.a .Iaddend.further object of the present invention to
provide an apparatus embodying a compact construction of parts that
can be economically produced for stressing the shank portion of a
fastener.
It is a still further object of the present invention to provide a
roll assembly wherein a tension rod is arranged to stress arbors
against opposite sides of a roll sleeve.
More particularly, the present invention provides an apparatus to
stress a fastener which includes a shank part extending to a flange
and having a plurality of spaced-apart holes spaced about an outer
peripheral part thereof to overlie a support member, and a
plurality of jack bolts threadedly engaged with the holes to
separately receive a torque, the jack bolts having end parts
extending from the holes against the support member under an
applied torque to develop a stress sufficient to tension the shank
part by applying a compressive reaction force against the support
member.
The support member may include a washer-like member that can be
pressed against a suitable face surface of the support structure. A
face surface of a washer-like member directed in a generally
confronting relation to the flange on the shank part of the
fastener can be hardened to withstand the force of the jack bolts
or, if desired, the face surface can be made soft relative to the
material of the jack .[.bolt.]. .Iadd.bolts .Iaddend.to avoid
upsetting .[.a.]. contacting end .[.face.]. .Iadd.faces .Iaddend.of
the jack bolts. The flange is provided with an opening or threads
to engage with a shank of a bolt, stud or shaft. When the flange
takes the form of a ring, a retainer such as a split ring, a snap
ring or interlocking fastener, is used to secure the flange to the
shank. The magnitude of the compressive force on each jack bolt is
only a fractional part of the stress imparted to the shank portion
of the fastener. A nut member.Iadd., .Iaddend.or a head portion of
a standard nut and bolt assembly, provides sufficient space for
threaded engagement of bolts about one or more bolt circles to
stress the shank part of the bolt to a magnitude that will at least
equal the strength of the bolt shank. Moreover, the apparatus of
the present invention is equally useful in specialized applications
including a roll assembly for a rolling mill in which the roll
assembly includes arbor members that are pulled together against
opposite sides of a sleeve under a tremendous clamping force. This
clamping force is developed by stress imparted to a shaft connected
at one end to one of the arbors and extending through an opening in
the other arbor so that an end portion of the shaft projecting
therefrom can be provided with a flange. The flange can carry a
multitude, e.g. between 10 and 500 or more jack bolts while
pressing against the arbor. Means other than a flange and jack
bolts can be used to stress the arbors against the roll sleeve. A
clamping force of more than 12,000,000 pounds on the roll sleeve
can be established. By this arrangement of parts, a roll assembly
with a roll body diameter of 50 inches and a width of 86 inches can
be provided for use as a backup roll in a hot strip rolling mill or
a cold rolling mill.
The invention further provides a roll assembly including a tubular
roll sleeve with opposite ends engaged for support by arbors, one
of which is connected to a tension rod extending through the roll
sleeve and through the other arbor, and means connected to the
other arbor and the tension rod for stressing the arbors against
opposite sides of the roll sleeve.
These features and advantages of the present invention as well as
others will be more fully understood when the following description
is read in light of the accompanying drawings, in which:
FIGS. 1A and 1B are longitudinal and end views, respectively, of
one embodiment of a fastener apparatus embodying the features of
the present invention;
FIGS. 2A and 2B are views similar to FIGS. 1A and 1B and
illustrating a second embodiment of the fastener apparatus;
FIGS. 3A and 3B are views similar to FIGS. 1A and 1B and
illustrating a third embodiment of the fastener apparatus;
FIG. 4 is an elevational view, partly in section, of a rolling mill
wherein a roll assembly includes a fastener apparatus embodying the
features of the present invention;
FIG. 5A is a longitudinal sectional view through a backup roll
assembly for a rolling mill embodying the features of the present
invention;
FIG. 5B is a partial end view of the roll assembly shown in FIG.
5A;
FIG. 6 is a view illustrating a further form of a roll assembly
embodying the features of the present invention.[...]. .Iadd.;
.Iaddend.
FIG. 7 is a partial sectional view illustrating a thrust collar
embodying the features of the present invention held in place by a
snap ring;
FIG. 8 is a partial sectional view illustrating a thrust collar
similar to FIG. 7 held in place by a split ring made from round
wire or bar stock;
FIG. 9 is a partial sectional view illustrating a thrust collar
similar to FIG. 7 held in place by a double split ring having a
square or rectangular cross section;
FIG. 10 is a view similar to FIG. 7 and illustrating a thrust
collar held in place by a bayonet connection;
FIG. 11 is a view similar to FIG. 10 and illustrating the use of
additional threaded fasteners for preventing rotation of the thrust
collar on a shaft member;
FIG. 12 is an .[.elevation.]. .Iadd.elevational .Iaddend.view
illustrating the use of the apparatus of the present invention for
clamping and centering a pulley on a shaft and use of the apparatus
of the invention to clamp a bearing assembly to the shaft;
FIG. 13 is a sectional view taken along lines 13--13 .[.in.].
.Iadd.of .Iaddend.FIG. 12;
FIG. 14 is a view similar to FIG. 13 but illustrating a further
embodiment of apparatus according to the present invention;
FIG. 15 is a sectional view illustrating a split thrust collar
embodying the features of the present invention;
FIG. 16 is a sectional view taken along lines 16--16 of FIG.
15;
FIG. 17 is an elevational view of a further embodiment of a thrust
collar embodying the features of the present invention clamped to a
shaft by a single threaded fastener;
FIG. 18 is a sectional view taken along lines 18--18 of FIG.
17;
FIG. 19 is an elevational view in section illustrating an
arrangement of two collars each embodying the features of the
present invention for mounting a bearing assembly on a shaft in a
bearing block; and Details 19A and 19B are enlarged views of
portions of the apparatus shown in FIG. 19; and
FIG. 20 is an elevational view in section illustrating apparatus of
the present invention for use with a spacer for clamping a shank
portion of a fastener to a member.
In FIGS. 1A and 1B, there is illustrated a fastener embodying the
features of the present invention for forming part of a
high-pressure pipe flange assembly which includes two pipe members
10 and 11 having pipe flanges 12 and 13.[.,.]. which are clamped
together .[.with a gasket 14.]. between the pipe flanges. A
plurality of fastener assemblies 15 is received in suitable
openings which are spaced about the outer peripheries of the pipe
flanges. Each fastener assembly 15 includes a bolt member having a
head portion 16, a shank portion 17 and a threaded end portion 18.
The threaded end portion is engaged with a nut member 19. The nut
member .[.function.]. .Iadd.functions .Iaddend.as a flange and
includes a plurality of drilled and tapped holes spaced about a
bolt circle located between the outer edge of the nut and the
threaded bore. A jack bolt 21 is received in each of the drilled
and tapped holes in the nut. The jack bolts may be of a standard
design and may be embodied as socket-head cap screws each having a
length sufficient to extend through tapped holes in the nut 19 and
present an end portion extending into compressive engagement with a
support surface 12A provided by flange 12. Because the jack bolts
have socket head portions, the length of the jack bolts must be
sufficient so that the threaded shanks can be advanced along the
tapped holes until a .[. desire.]. .Iadd.desired .Iaddend.torque is
established without contact between the socket-head portion 21A and
the nut member 19. It will be understood that the nut member 19 can
be rotated on the threaded end portion 18 to contact or form a
small gap between the nut member and surface 12A of flange 12. The
jack bolts 21 are then rotated until the end portions extend from
the nut member to contact flange 12. It is preferable to torque the
jack bolts in a patterned sequence such as by torquing jacks bolts
at opposite sides of the nut and then advancing to a next jack bolt
in the bolt circle. A torque wrench or other control means such as
an impact wrench with a variable torque setting can be used to
tighten the jack bolts. Also, a lubricant such as graphite can be
applied to the threads of the jack bolts to facilitate torquing
thereof.
To further illustrate the utility of the present invention, let it
be assumed that a fastener assembly 15 is 11/2 inches,
course-thread series, with six threads per inch. Ten jack bolts can
be arranged in a bolt circle in the nut member. When all the jack
bolts are torqued to 60 ft-lb, the shank part 17 of the fastener is
stressed to a maximum stress of 93,000 psi. By way of comparison,
for example, the torque required to obtain the maximum stress level
with a standard nut is 2700 ft-lb and this requires 270 pounds of
force on a ten-foot lever arm of a torque wrench. This same stress
level can be developed by applying 60 pounds of force on a one-foot
lever arm of a torque wrench to each of the ten jack bolts. In this
example, the maximum total clamping force on the flange using
fastener assembles of the present invention is 120,000 pounds. By
way of a further example, a bolt size of 31/2 inches with a course
thread series of four threads per inch can be provided with sixteen
jack bolts in the nut member thereof. The fastener can be stressed
to 96,000 pounds psi by torquing each jack bolt to 480 ft-lb which
can be accomplished by applying 48 pounds of force to a ten-foot
long lever arm of a torque wrench. By way of comparison, 40,000
ft-lb of torque must be .[.applies.]. .Iadd.applied .Iaddend.to the
same nut member of this fastener assembly which is too high for
torquing directly by a wrench.
FIGS. 2A and 2B illustrate a further embodiment of fastener
assembly 22 to anchor a structure, a portion of which is identified
by reference numeral 23 to a foundation 24. The structure 23
includes a suitable opening through which the shank portion 25
extends. A projecting end portion of the shank portion 25 is
provided with threads to engage with threads on a collar 26 which,
as is apparent from FIG. 2B, takes the form of a sleeve ring. The
concentric bolt circles have their center situated to coincide with
the axial center of the threads in the collar 26. A staggered or
alternating arrangement of bored and tapped holes is provided in
the collar, and a jack bolt 27 is threaded in each tapped hole.
Each jack bolt includes a threaded portion that extends to an
elongated and cylindrical shank 27A. The shank is supported by the
bore in the nut to prevent buckling along the length of the shank.
At the terminal end of the shank there is .[.preferable.].
.Iadd.preferably .Iaddend.provided a chamfered end which extends
from the collar 26 into engagement with a ring 28 which can be
hardened to better withstand the clamping force developed by the
jack bolts which press the ring against the structure 23. The ring
28 can be made of relatively soft metal or other material so that
the material of the ring will upset under the .[.applied force.].
.Iadd.force applied .Iaddend.by the jack bolts and, thereby, avoid
.[.an.]. upsetting of the end face of the bolts in contact with the
ring. The end of each jack bolt which is opposite the chamfered
portion extends from the ring and .[.has.]. has a head to receive a
socket coupled to a suitable torque wrench. For illustrative
purposes only, there are twenty-four jack bolts arranged in the
flange with twelve jack bolts spaced about each of the bolt centers
in an alternating arrangement. It is to be understood, of course,
that the number of jack bolts that can be arranged in a given
collar member is selected according to the desired stress that is
to be imposed on the shank portion of the fastener. The jack bolts
can be arranged in only one bolt circle.Iadd., .Iaddend.but two or
more bolt circles may be used to accommodate a required number of
jack bolts.
In FIGS. 3A and 3B, a third embodiment of the fastener assembly
according to the present invention is illustrated which differs
from .[.that.]. .Iadd.those .Iaddend.already described by the fact
that jack bolts 30 are engaged in threaded openings spaced about a
bolt circle in the head portion of a conventional bolt 32. The bolt
shown in FIG. 3A forms part of an anchor for a machine element 33.
A shank portion 34 of the bolt member extends through an opening in
the machine element and projects into a foundation where it is
anchored in a suitable, well-known manner. As shown in FIG. 3B, the
jack bolts are embodied as socket-head cap screws having socket
portions at their ends projecting from the head of the fastener.
The opposite ends of the jack bolts are chamfered and engage with a
hardened steel support ring 35.
In FIG. 4, there is illustrated a still further embodiment of the
present invention in which a fastener assembly 40 is part of a roll
assembly for use in a 2-inch rolling mill. The rolling mill
includes spaced-apart mill housings 41 and 42 each having window
openings into which bearings chocks are received and carry bearings
on journals at opposite ends of upper and lower roll assemblies 44
and 45. An end portion of each roll assemblies extends to coupling
members 47 of spindles which are coupled to a drive at one side of
the mill stand. A screwdown is provided in the mill housings for
adjusting one roll assembly relative to the other. The rolls are
held apart by roll balance cylinders, not shown. Each roll assembly
includes spaced-apart arbors 48 and 49 mounted in bearings received
in bearing chocks 50 and 51, respectively. A tension shaft 52 has a
threaded end portion engaged with threads formed in an opening in
arbor 48 and extends through an opening in arbor 49. Shaft 52 is
centered and supported by a collar 54 on a shaft 52 in the opening
in arbor .[.48.]. .Iadd.49.Iaddend.. Projecting outwardly beyond
the collar portion 54 is a threaded end portion, the threads of
which engage with threads on the flange 55. A hardened ring 56 is
positioned between the flange 55 and arbor 49. The ring can be made
of a relatively soft material, if desired, to prevent upsetting of
the ends of the jack bolts as described hereinbefore. The flange is
provided with a plurality of spaced-apart drilled and tapped holes,
each of which receives a jack bolt 57. A roll sleeve 59 has an
enlarged central bore which is sufficiently large so that an
annular gap is formed between the roll sleeve and the tension
shaft. Opposite end surfaces of the roll sleeve include an annular
support surface 60 and an outwardly-tapering conical clamping
surface 61 which .[.engages.]. .Iadd.engage .Iaddend.with mating
surfaces formed in the arbors. The clamping force which can be
developed by the jack bolts is sufficient to maintain the arbors
tightly clamped to the roll sleeve even when the roll assembly is
subjected to a massive separating force occurring during the
rolling operation. The rolling forces are transmitted from the
sleeve while supported only at its ends by the arbors. A gap or
space between the sleeve and the tension member is intended and
this space is so great that no contact exists therebetween.
.[.FIG. 5.]. .Iadd.FIGS. 5A and 5B .Iaddend.illustrates a further
embodiment of the present invention embodied as a backup roll
assembly for 4-high rolling mill. As is well known in the art, two
backup roll assemblies are supported by spaced-apart mill housings
to transfer rolling loads from relatively small diameter work rolls
to the mill housings. The backup roll assembly shown in FIG. 5
includes spaced-apart bearing chocks 60 and 61, each of which
supports bearing assemblies that are mounted on arbors 62 and 63,
respectively. Arbor 62 has a central bore that is enlarged by a
counterbore that is threaded and receives the threaded end portion
of a tension rod 64. The tension rod extends through a central
opening in arbor 63 where the rod is held in a central position by
a collar 65. An end portion of the tension rod extends from the
arbor 63 and has threads that mate with threads formed on a collar
66. A hardened ring 67 is positioned between the arbor 63 and the
collar for engagement with the end parts of the multitude of jack
bolts 68. For the purpose described previously, the hardened ring
can be replaced with a ring made of relatively soft metal. Merely
for purposes of illustration, it is contemplated that between 200
and 250 jack bolts .[.are.]. .Iadd.be .Iaddend.spaced apart about
six different and concentric bolt circles to stress the tension rod
64 which has a nominal diameter of about 15 inches. The jack bolts
can be develop at least 6,000,000 pounds and up to 12,000,000
pounds of stress on the tension rod which is sufficient to
withstand a nominal rolling load of 12,000,000 pounds on the roll
sleeve. This is 300% more than an anticipated rolling load. The
roll sleeve can have a nominal outside diameter of 50 inches and a
length of 86 inches. The opposite ends of a roll sleeve are
supported by the arbors in the same manner as described previously
in regard to the embodiment of FIG. 4.
A still further embodiment of the present invention
.[.illustrated.]. .Iadd.illustrating .Iaddend.a rolling mill
arrangement using a pair of cooperating grooved roll assemblies 70
and 71 is shown in FIG. 6. The roll assemblies cooperate to form a
roll gap having a square configuration. .[.The.]. .Iadd.Each of the
.Iaddend.roll assemblies .[.each.]. includes a roll collar 72 which
is supported on an end portion of a shaft 73 extending in
cantilevered fashion from a bearing housing 74 wherein an
anti-friction bearing 75 supports the shaft. Between the collar 72
and the shaft 73 there is an annular tapered sleeve 76 which is
pressed into a tapered gap between the roll collar and the shaft by
a plurality of jack bolts 77 spaced apart along a bolt circle
defined on a nut collar 78. The collar 78 includes a central
threaded portion which is threadedly engaged with threads on the
end of the shaft 73. To facilitate assembly and disassembly of the
roll sleeves on the shafts, sleeve 76 is provided with a large
tapered angle, e.g., 12 degrees. The tension bolts 77 can be
tightened to relatively low torque levels for forcing the tapered
sleeve tightly between the collar 72 and the shaft 73.
In FIGS. 7-11 additional embodiments .Iadd.are illustrated
.Iaddend.of a fastener apparatus .[.are illustrated.]. according to
the present invention for retaining an anti-friction bearing 81 on
a bearing-seat surface of a shaft 82. An inner race 83 of the
bearing is pressed against a conventional shoulder surface formed
on shaft 82 by a fastener assembly. In FIG. 7, the fastener
assembly includes a ring 84 which is formed with a plurality of
drilled and tapped holes in a bolt circle at spaced-apart locations
with the tapped hole extending parallel to the bore in the ring.
Jack bolts .[.85.]. .Iadd.86 .Iaddend.in the form of socket set
screws are threaded in the drilled and tapped holes so that end
portions extend from the ring into engagement with the inner race
83 of the bearing, as shown. A snap ring 85 is placed in a groove
located in the end of the shaft to form an abutment surface that
prevents displacement of ring 84 from the shaft when the jack bolts
are torqued. In the embodiment of FIG. 8, a ring 87 is provided
with drilled and tapped holes as described previously in regard to
FIG. 7 for receiving jack bolts 88 which take the form of
socket-cap screws. Ring 87 is held in place on shaft 82 by a snap
ring 89 that is fitted in a circular opening to engage a portion of
the ring 87 when jack bolts 88 are torqued to a desired extent.
In FIG. 9, a ring 90 is provided with drilled and tapped holes as
shown and described previously in regard to FIG. 7. Jack bolts 91
have shank portions engaged in the drilled and tapped holes so that
end portions of the jack bolts extend from the ring 90 into
engagement with the inner race of bearing 81. The ring 90 is
retained on the shaft against a force developed by the jack bolts
by a double-split ring 92 having a square or rectangular
cross-sectional shape. The socket head portions of jack bolts 91
are provided with drilled openings extending transversely to the
.[.length.]. .Iadd.lengths .Iaddend.of the .[.bolt.]. .Iadd.bolts
.Iaddend.and a length of wire is threaded through openings of the
various jack bolts to interlock them and prevent unwanted twisting
in the threads in the collar after the jack bolts are torqued to
produce the desired force on the inner race of the bearing.
In FIG. 10, ring 93 is provided with drilled and tapped holes
arranged in a bolt circle in the same manner as described in regard
to the embodiment of FIG. 7 and a socket-set screw is provided in
each of the drilled and tapped holes. The .[.inter.]. .Iadd.inner
.Iaddend.bore of the ring is formed with projecting lug portions
separated from one another by a space to form a part of a bayonet
connection. The end portion of shaft 82 is provided with milled
slots spaced about the circumference thereof so that a slot in the
shaft can receive a projecting lug of the ring 93. The ring is
advanced toward the bearing until the lug is received in a recess
94 whereupon ring 93 is rotated so that the lug of the ring and a
lug of the shaft contact each other. Thereafter the socket set
screws are torqued to a desired .[.extend.]. .Iadd.extent
.Iaddend.to establish a force of a desired magnitude on the inner
race of the bearing. In FIG. 11, a ring 95 is provided with drilled
and tapped holes in a bolt circle as shown and described in regard
to the ring 84 in FIG. 7. Ring 95 is additionally provided with
radially extending drilled and tapped holes into which there
.[.is.]. .Iadd.are .Iaddend.received .[.a.]. socket set .[.screw.].
.Iadd.screws .Iaddend.96 .[.is advanced along.]. .Iadd.to be
advanced along .Iaddend.the threads in the ring until an end
portion protrudes from the ring into a drilled hole in shaft 82.
The screws 96 form an interlocking member extending between the
ring 95 and shaft 82 to prevent ring 95 from rotating. The jack
bolts .[.85.]. .Iadd.86 .Iaddend.are arranged in drilled and tapped
holes in a bolt circle such that these holes do not intersect with
the drilled and tapped holes containing screws 96. The ring 95 is
retained on shaft 82 by a ring 92 in the same manner as described
hereinbefore in the embodiment of FIG. 9.
In FIG. 12, there is illustrated a shaft 100 on which there
.[.is.]. .Iadd.are .Iaddend.positioned at a spaced-apart locations,
a sheave 101 and a bearing assembly 102. Fastener assemblies 103
and 104 are arranged on shaft 100 at opposite sides of the sheave
101 and a fastener assembly 105 and a retainer plate 106 are
arranged on shaft 100 at opposite sides of the bearing assembly
102. The retainer plate is secured to the shaft by a pin 107 that
extends through a diametrical opening in the retainer plate and an
aligned opening in shaft 100. In a similar way, fastener assemblies
103, 104 and .[.106.]. .Iadd.105 .Iaddend.are secured to shaft 100
by a pin 107. Each of the fastener assemblies includes .[.a ring
108.]. .Iadd.rings .Iaddend.having drilled and tapped holes spaced
about a bolt circle with a jack .[.bolt.]. .Iadd.rings .Iaddend.108
received in each of the drilled and tapped holes. The jack bolts in
the embodiment of FIG. 12 comprise socket-head cap screws. End
portions of the jack bolts extend from rings 103 and 104 into
engagement with an annular section of the sheave. The jack bolts
are torqued to a desired extent so that the sheave 101 is clamped
between the fastener assemblies under sufficient force to prevent
rotation of the sheave on shaft 100. The jack bolts 108 in
.[.ring.]. .Iadd.fastener assembly .Iaddend.105 are torqued to a
sufficient extent so that the bearing assembly 102 is pressed
between ring 105 and ring 106 so that the bearing assembly cannot
move in an axial direction along shaft 100.
FIG. 13 illustrates a typical section through any one of the rings
103, 104 and 105. There are, as shown, two jack bolts in each ring,
although three or more jack bolts can be provided, if desired. In
FIG. 14, there is illustrated a modification to the fastener
assemblies 103, 104 and 105. The modification provides that socket
set screws are threadedly engaged with threads formed in a
diametrically-extending opening. The socket set screws are rotated
so that end portions extend into drilled openings in shaft
.[.101.]. .Iadd.100.Iaddend.. In FIGS. 15 and 16, a still further
embodiment of the fastener assembly of the present invention is
illustrated in which a bearing member 111 is pressed against a
shoulder, not shown.Iadd., .Iaddend.by a fastener assembly that
includes a ring 112 that is circumferentially divided into two
parts as shown in FIG. 16. Drilled and tapped holes are provided in
the ring at spaced-apart locations and receive socket set screws
.Iadd.110 .Iaddend.which can be rotated under an applied torque
which is sufficient to force the bearing 111 against its support
shoulder and displace the ring against a collar section 113 formed
on the end of shaft 114. The divided parts of ring 112 are secured
together by socket-head cap screws 115 extending into drilled and
tapped holes in ring part 112A from drilled holes in ring part
112B. By this construction of parts, the need for a snap ring or
other forms of retaining devices as illustrated and described in
regard to FIGS. 7-11 can be eliminated.
In FIGS. 17 and 18, a fastener assembly is provided with jack bolts
threadedly engaged in openings in a ring 116 in a manner already
shown and described in regard to FIGS. 15 and 16. A saw cut is
formed in ring 116 so that the ring can be clamped onto a shaft 117
by a socket-head cap screw 118 at a desired site along the
shaft.
In FIGS. 19, 19A and 19B, there is illustrated fastener apparatus
for securing a pulley 120 to a shaft 121. Opposite ends of the
shaft 121 are supported by bearing assemblies 122 and 123. A spacer
ring 124 is arranged at each of opposite sides of the pulley. In
bearing assembly 123, there is an anti-friction bearing 125 having
an inner race that abuts at one face against ring 124 and at the
opposite face abuts against a snap ring 126. The outer ring of the
anti-friction bearing is supported in a housing 123A. Bearing
assembly 122 includes an anti-friction bearing 127 having an inner
race that abuts on one side against ring 124 and at the opposite
side .[.there is.]. a fastener assembly 128. A fastener assembly
129 is supported in a bearing housing 122A to press an outer race
of the bearing assembly against a shoulder formed in the bearing
housing. As shown in FIG. 19A, the fastener assembly 127 includes a
ring 130 which is constructed in the same manner as ring 84
described heretofore and shown in FIG. 7. The jack bolts 86 of the
fastener assembly are rotated under a desired torque so that end
portions extending from the ring .[.engaged.]. .Iadd.engage
.Iaddend.with the inner race of the bearing assembly. The ring 130
engages .Iadd.with .Iaddend.a snap ring 131 located in a suitable
groove formed in an end portion of shaft 121. In FIG. 19B, the
fastener assembly 129 is shown and embodies a construction which is
the same as fastener assembly .[.127.]. .Iadd.128 .Iaddend.except
for the provision of a recess in an end face thereof to engage with
a retainer ring 132 that is located in a suitable recess formed in
the bearing housing 122A. The jack bolts of each fastener assembly
.[.127.]. .Iadd.128 .Iaddend.and 129 can be torqued to the desired
extent so that the inner and outer races, respectively, of the
bearing assembly are pressed against the bearing housing. In this
way, the outer race can be clamped in the bearing housing and the
inner race can be torqued to establish a desired clamping force
between rings 124, .[.sheave.]. .Iadd.pulley .Iaddend.120 and the
inner race .Iadd.of anti-friction .Iaddend.bearing 125.
In FIG. 20, there is illustrated an anchor bolt 140 having a shank
portion that extends into a .[.foundation.]. .Iadd.member 147
.Iaddend.and a threaded end portion 141 that is engaged with
threads formed in a bore of a ring 142 forming part of a fastener
assembly according to the present invention. A multitude of drilled
and tapped holes are formed in two concentric bolt circles at
spaced-apart locations and in each drilled and tapped hole there is
threadedly engaged a jack .[.bolts.]. .Iadd.bolt .Iaddend.143. The
jack bolts in the embodiment of FIG. 20 take the form of
socket-head cap screws having end portions that project from ring
142 into engagement with one of two washer members 144 and 145. The
washer members are, in turn, carried by a collapsible spacer 146
positioned on a member 147. The member 147 may be part of a machine
or any well-known element which must be anchored to a foundation or
support structure. The washers 144 and 145 are constructed from
material having a preselected hardness which is predetermined
according to the forces required to support the member 147. The
washers are made from sufficiently hard material such as metal or
plastic so that the washers can sustain the load imposed thereon by
the jack bolts without yielding under the imposed load. On the
other hand, the washers are sufficiently soft so that the metal of
the end faces of the jack bolts will not upset under the applied
load. Also, it is important to prevent destruction of the drilled
and tapped holes in ring 142 in the event of an excessive torque
applied to any one or more of the jack bolts. In this way, the
washers can yield under the excessive load. The spacer 146 includes
web and flange sections 146A which will break or shear in the event
.[.the.]. .Iadd.that .Iaddend.spacer is subject to an excessive
load. The spacer thereby prevents damage to other parts. Also, the
spacer can be severed by, for example, a cutting torch in the event
the threads of the jack bolts are rendered partially inoperative
due to rust or other contaminants. Such a condition of the jack
bolts may occur after a long period of continued use of the
fastener assembly. Thus, by relieving the fastener assembly of the
clamping force, which can be large, the jack bolts may be easily
rotated for removal and servicing from .[.sleeve.]. .Iadd.ring
.Iaddend.142.
* * * * *