Chamfering reamer with trip shoulder

A adjustable chamfering reamer used in automated threading machines for reaming the ends of pipe or conduit. The adjustable chamfering reamer has an inner reamer insert adjustably installed within a generally cylindrical outer sleeve. The front of the outer sleeve has circumferentially spaced forwardly extending projections with a flat inwardly and rearwardly angled reaming surface and a trip shoulder at the bottom thereof. The inner reamer insert has a trunched conical forward end defined by a plurality of circumferentially spaced longitudinal wings extending rearwardly and outwardly from the forward end and the exterior of the wings are curved reaming surfaces. When assembled, the wings are positioned between the projections of the outer sleeve in alternating relation. When viewed from the side, the overlapped reaming surfaces and shoulders form a plurality of rearwardly extending flat-bottom V-shaped grooves. The width of the flat-bottom V-shaped groove can be adjustably altered by positioning the inner reamer insert relative to the outer sleeve to receive pipe or conduit of various wall thicknesses and to ream the exterior and interior diameters at the end of the pipe or conduit simultaneously. The adjustable reamer is secured in the die head of a threading machine and receives the end of a pipe or conduit during the threading operation.

BACKGROUND OF THE INVENTION 
1. FIELD OF THE INVENTION 
This invention relates generally to reamers, and more particularly to an 
adjustable chamfering reamer for use in threading machines which has an 
inner reamer member adjustably carried in an outer reaming member such 
that the reaming surfaces can be selectively positioned relative to one 
another to chamfer the exterior and interior of the threaded end of pipe 
or conduit and which has a trip shoulder for activating the chaser holder 
of the threading head to release the chamfered piece upon completion of 
the threading and chamfering operation. 
2. BRIEF DESCRIPTION OF THE PRIOR ART 
Chamfering reamers are secured by an adjustable draw bar in the threading 
head member of a threading machine and chamfer the ends of a pipe or 
conduit to remove the burr from the inside or outside diameter of the pipe 
or conduit after it has been threaded. 
Some reamers, such as those manufactured by Teledyne Landis Machine of 
Waynesboro, Pennsylvania have fixed reaming surfaces and are designed to 
chamfer the inside and outside diameter of the pipe or conduit 
simultaneously. This type of reamer has a fluted body forming longitudinal 
wings which have an integral rearwardly extending, flat-bottom, generally 
V-shaped groove in the front portion of each wing. The converging inner 
sides of the V-groove chamfer the material and the flat bottom of the 
V-groove serves as a stop bar during the threading operation by forceably 
contacting the end of the pipe or conduit sufficient to activate a trip 
release within the threading machine to release the chamfered piece. 
Prior art reamers having fixed reaming surfaces frequently become worn and 
require replacement or re-grinding of the cutting surfaces. The suggested 
method of resharpening or grinding is to grind on the flat side of each 
wing. This seriously impairs the useful life of the reamer because it 
reduces the cross section of the wing and changes the geometry of the 
cutting edges. The thinner reworked wings are often broken because the 
outer side wall of the flat bottom V-shape is thin and has a vulnerable 
stress point. The flat bottom tripping surface of the V-groove does not 
provide a desirable relief angle, and results in chip build- up which 
often causes damage to the first threads or even tearing off the end of 
the pipe. The flat bottom tripping surface of the V-groove is 
perpendicular to the longitudinal axis, and will also often gouge or 
damage the end of the pipe or conduit when forcible contact is made during 
the tripping sequence. 
Another common problem with chamfering reamers is the down-time or loss of 
production caused by the necessity of frequent replacement and re-setting 
of a new reamer to accommodate pipe or conduit having a different wall 
thickness. 
Teledyne Landis Machine of Waynesboro, Pennsylvania at one time marketed a 
two-piece reamer designed to chamfer the inside and outside diameter of 
the pipe or conduit. The reamer had a truncated nose piece with reaming 
wings which was bolted onto the front of a fluted body to form a 
rearwardly extending, flat-bottom, generally V-shaped groove. The 
flat-bottom of the V-groove served as a stop bar during the threading 
operation by forceably contacting the end of the pipe or conduit 
sufficient to activate a trip release within the threading machine to 
release the chamfered piece. The flat bottom tripping surface of the 
V-groove was perpendicular to the longitudinal axis and did not provide a 
relief angle. The reaming surfaces were fixed, and the nose piece was not 
adjustably positioned relative to the fluted body. 
Other two-piece reamers are known in the art. There are several patents 
which disclose reamers and cutting tools of various configuration. 
German patent 25 18 187 discloses a manual two-piece deburring tool 
designed to be secured in a handle and held in the hand to simultaneously 
chamfer the inside and outside diameter of the pipe or conduit. The reamer 
has a toothed inner cutter which is carried in an outer cutter member with 
the teeth of the inner cutter member pointing into the gaps between the 
teeth of the outer cutter member to form a V-shaped groove with the cutter 
surfaces forming a sharp bottom V-groove. The tool would not be suitable 
for use in a threading machine and there is no provision of a tripping 
shoulder to activate a trip release within the threading machine. 
Tyne, U.S. Pat. No. 2,188,584 discloses a reamer designed to chamfer the 
inside and outside diameter of the pipe or conduit. The reamer has a 
central body with slots which receive replaceable reamer blade inserts 
which are bolted into the front of the body by a central bolt and washer. 
The removable reamer insert blades each have an integral rearwardly 
extending, flat-bottom, generally V-shaped groove formed therein. The flat 
bottom of the V-groove serves as a stop surface to activate a trip release 
within the threading machine to release the chamfered piece. The flat 
bottom tripping surface of the V-groove is perpendicular to the 
longitudinal axis and does not provide a relief angle. The reaming 
surfaces are fixed, and not capable of being adjustably positioned 
relative to one another. 
Christensen, U.S. Pat. No. 4,468,829 discloses manual two-piece cleaning 
and deburring tool designed to be held in the hand to clean and deburr 
spent cartridge cases. The tool has an inner member carried in an outer 
member with the forward ends of the inner and outer member forming a 
segmented V-shaped groove which will deburr the interior and exterior 
surfaces of a spent cartridge case when the cartridge case is rotated 
relative to the tool. This tool would not be suitable for use in a 
threading machine and there is no provision of a tripping shoulder to 
activate a trip release within the threading machine. 
Phillips, U.S. Pat. No. 4,930,946 discloses a two-piece chamfering reamer 
having an inner body with a truncated conical forward end defined by 
circumferentially spaced longitudinal wings with a reaming surface on 
their exterior and a trip shoulder at their rearward end and an outer 
sleeve which is secured on the inner body. The outer sleeve has forwardly 
extending projections with inwardly angled reaming surfaces. When 
assembled, the reaming surfaces of the projections are in circumferential 
alignment with the wings and the inner body is not adjustably positioned 
relative to the outer sleeve. 
The present invention is distinguished over the prior art in general, and 
these patents in particular by an adjustable chamfering reamer used in 
automated threading machines for reaming the ends of pipe or conduit. The 
adjustable chamfering reamer has an inner reamer insert adjustably 
installed within a generally cylindrical outer sleeve. The front of the 
outer sleeve has circumferentially spaced forwardly extending projections 
with a flat inwardly and rearwardly angled reaming surface and a trip 
shoulder at the bottom thereof. The inner reamer insert has a truncated 
conical forward end defined by a plurality of circumferentially spaced 
longitudinal wings extending rearwardly and outwardly from the forward end 
and the exterior of the wings are curved reaming surfaces. When assembled, 
the wings are positioned between the projections of the outer sleeve in 
alternating relation. When viewed from the side, the overlapped reaming 
surfaces and shoulders form a plurality of rearwardly extending 
flat-bottom V-shaped grooves. The inner reaming surfaces provide 
sufficient clearance to pass under the thread chaser to ream the inside of 
the pipe or conduit while the outer reaming surfaces of the projections 
pass between the chasers to ream the outside and provide a limit or trip 
shoulder. The width of the flat-bottom V-shaped groove can be adjustably 
altered by positioning the inner reamer insert relative to the outer 
sleeve to receive pipe or conduit of various wall thicknesses and to ream 
the exterior and interior diameters at the end of the pipe or conduit 
simultaneously. 
SUMMARY OF THE INVENTION 
It is therefore an object of the present invention to provide an adjustable 
reamer for simultaneously chamfering the outside and inside diameters at 
the end of a threaded pipe or conduit during the threading operation. 
It is another object of this invention to provide an adjustable reamer for 
chamfering the outside and inside diameters at the end of a threaded pipe 
or conduit which has a trip shoulder that contacts the end of the pipe or 
conduit during the threading operation to activate a trip release 
mechanism within the die head of a threading machine to release the 
threaded piece after the predetermined number of threads have been cut. 
Another object of this invention is to provide an adjustable reamer having 
an inner reamer insert adjustably installed within a generally cylindrical 
outer sleeve to define a conical, flat-bottom, V-shaped reaming surface 
wherein the width of the V-shaped reaming surface can be adjustably 
altered by positioning the inner reamer insert relative to the outer 
sleeve to receive pipe or conduit of various wall thicknesses and to ream 
the exterior and interior diameters at the end of the pipe or conduit 
simultaneously. 
Another object of this invention is to provide an adjustable reamer having 
reaming surfaces and a trip shoulder which may be easily renewed by 
grinding when they become worn. 
Another object of this invention is to provide an adjustable reamer with 
inwardly converging reaming surfaces and a trip shoulder at the inward 
ends thereof which are angled relative to one another to prevent damage to 
the end of the pipe or conduit during the reaming and tripping operation. 
A further object of this invention is to provide an adjustable reamer 
having a flat-bottom, V-shaped conical reaming portion for chamfering the 
outside and inside diameters at the end of a threaded pipe or conduit 
simultaneously and an angular trip shoulder at the bottom of the V-shape 
which forceably contacts the end of the pipe or conduit to limit the 
reaming operation and provides sufficient force to trip the threading head 
of the threading machine after the predetermined number of threads have 
been cut. 
A still further object of this invention is to provide a reamer which is 
simple in construction and is rugged and durable in use. 
Other objects of the invention will become apparent from time to time 
throughout the specification and claims as hereinafter related. 
The above noted objects and other objects of the invention are accomplished 
by an adjustable chamfering reamer used in automated threading machines 
for reaming the ends of pipe or conduit. The adjustable chamfering reamer 
has an inner reamer insert adjustably installed within a generally 
cylindrical outer sleeve. The front of the outer sleeve has 
circumferentially spaced forwardly extending projections with a flat 
inwardly and rearwardly angled reaming surface and a trip shoulder at the 
bottom thereof. The inner reamer insert has a truncated conical forward 
end defined by a plurality of circumferentially spaced longitudinal wings 
extending rearwardly and outwardly from the forward end and the exterior 
of the wings are curved reaming surfaces. When assembled, the wings are 
positioned between the projections of the outer sleeve in alternating 
relation. When viewed from the side, the overlapped reaming surfaces and 
shoulders form a plurality of rearwardly extending flat-bottom V-shaped 
grooves. The inner reaming surfaces provide sufficient clearance to pass 
under the thread chaser to ream the inside of the pipe or conduit while 
the outer reaming surfaces of the projections pass between the chasers to 
ream the outside and provide a limit or trip shoulder. The width of the 
flat-bottom V-shaped groove can be adjustably altered by positioning the 
inner reamer insert relative to the outer sleeve to receive pipe or 
conduit of various wall thicknesses and to ream the exterior and interior 
diameters at the end of the pipe or conduit simultaneously.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
For ease of understanding, a brief description of the manner in which the 
adjustable chamfering reamer with trip shoulder is used will be given 
first followed by a detailed description of the structural features of the 
reamer. 
Referring to the drawings by numerals of reference, there is shown somewhat 
schematically in FIG. 1, a conventional tripping die head H of a pipe or 
conduit threading machine having an adjustable chamfering reamer R in 
accordance with the present invention installed in the die head bore 
adjacent the chaser holders CH. The reamer R has a tailpiece TP at its 
rearward end which is received in the end of a driver member D coupled to 
the spider S of the conventional internal tripping mechanism which opens 
the jaws of the die head. The reamer tailpiece TP is threadedly received 
on the forward end of a clamping rod CR. The reamer R is operatively 
coupled to the existing tripping die head components and has a trip 
shoulder at the rearward end of the reaming surfaces which, after the 
reaming operation, acts as the stop bar for the internal tripping 
mechanism. The clamping rod CR extends outwardly at the rear of the 
threading machine for easy access and positions the reamer trip shoulder 
to trip the release after the predetermined number of threads have been 
cut. 
As the threaded end of a pipe or conduit being threaded progresses into the 
die head, it is received between the tapered reaming surfaces (described 
hereinafter) at the forward end of the reamer R. The reamer R has been 
positioned such that the trip shoulder of the reamer will contact the end 
of the pipe or conduit after the predetermined number of threads have been 
cut. The tapered surfaces at the forward end of the reamer R reams and 
chamfers the external and internal diameter of the pipe or conduit and 
after the predetermined number of threads have been cut, the end of the 
pipe or conduit contacts the trip shoulder and provides sufficient 
resistance force to actuate the internal trip mechanism or spider to 
release the workpiece and end the cycle. 
Referring now to FIG. 2, the preferred adjustable chamfering reamer R is 
shown in an unasssembled condition and in FIG. 3, in the assembled 
condition. The adjustable chamfering reamer R is capable of chamfering 
both the outside and inside diameters of a pipe or conduit simultaneously, 
and is adjustable to receive pipe or conduit of various wall thicknesses. 
The reamer R has a cylindrical outer sleeve 10 and an adjustable inner 
reamer insert 30 which is longitudinally adjustable relative to the outer 
sleeve, as will be explained hereinafter. 
Referring additionally to FIGS. 4, 5, 6, and 10, the cylindrical outer 
sleeve 10 has a rectangular extension or tailpiece 11 which is square in 
cross section. A threaded bore 12 extends inwardly from the rearward end 
of the tailpiece 11 and terminates in a shoulder 13. The threaded bore 12 
receives the clamping rod accessory of the threading machine. The 
cylindrical outer sleeve 10 has a central bore 14 extending inwardly from 
the forward end and terminating in a smaller bore 15 defining a shoulder 
16 therebetween. The outer diameter of the outer sleeve 10 is of 
sufficient size to be received in the bore of the die head of the 
threading machine. 
The forward end of the outer sleeve 10 has a plurality of circumferentially 
spaced cut-away portions 17 extending rearwardly to define a plurality of 
projections 18. The preferred outer sleeve 10 has four projections 18 
extending laterally from the horizontal and vertical axes X and Y, but may 
have anywhere from two to six. The interior surface at the front end of 
each projection 18 extends angularly rearward and inwardly relative to the 
longitudinal axis of the outer sleeve to form a reaming surface 19 which 
terminates in a trip shoulder 20 that extends radially inward to the 
central bore 14. The preferred angle of the reaming surface 19 is from 
20.degree. to 30.degree. relative to the longitudinal axis. The 
diametrical distance between the outer ends of the reaming surfaces 19 is 
greater than the exterior diameter of the pipe or conduit being reamed and 
the inner end of the reaming surface where it joins the shoulder 20 is 
smaller than the exterior diameter of the pipe or conduit. 
As shown in FIG. 10, when viewed from the front end, the projections 18 
each have diametrically opposed flat leading edge surfaces L and flat 
trailing edge surfaces T spaced generally parallel thereto in a clockwise 
direction from the leading edge surface. Because the flat reaming surfaces 
19 extend laterally from the X and Y axes, the distance d1 from the center 
of the outer sleeve to the leading edge L is shorter than the distance d2 
from the center to the trailing edge T. Thus, the inclined reaming surface 
19 extends outwardly from the leading edge L to the trailing edge T 
relative to the central axis of the sleeve. The inner end of the reaming 
surface 19 where it joins the trip shoulder 20 is cut on a radius r1 and 
therefore, the trailing edge T of the reaming surface 19 is wider than the 
leading edge L at the juncture of the reaming surface 19 with the trip 
shoulder 20. Referring again to FIG. 5, the trip shoulder 20 slopes 
upwardly toward the front of the outer sleeve 50 at an angle A1 from the 
leading edge L to the trailing edge T to form an angled tripping surface 
transverse to the longitudinal axis. The preferred angle A1 is from 
approximately 1.degree. to 3.degree.. 
It should be understood from the foregoing description that as a tubular 
pipe or conduit is fed into the front portion of the outer sleeve 10 in 
alignment with the longitudinal axis, the leading edge L of the reaming 
surfaces 19 will serve as a cutting surface to perform any cutting 
necessary to remove burrs or material which extend radially outward from 
the exterior diameter, and as the pipe or conduit continues to be fed onto 
the reaming surfaces 19, the exterior diameter will contact the inwardly 
angled reaming surface 19 somewhere near the trailing edge since the 
trailing edge T is wider than the leading edge L. Thus, the reaming 
surfaces 19 provide an angled cutting surface with minimum pipe contact 
area and a smooth reaming surface for chamfering the exterior diameter. 
Continued longitudinal feeding of the pipe or conduit onto the reaming 
surfaces will cause its interior diameter to contact the reaming surface 
at its approximate transition with the trip shoulder 20 near the trailing 
edge T to apply the tripping force necessary to activate the tripping 
mechanism, and the angled trip shoulder 20 provides a raised trailing 
surface to prevent galling. 
Referring now to FIGS. 2, 7, 8, 9, and 11, the adjustable inner reamer 
insert 30 is a generally cylindrical member having a truncated conical 
front portion 31 and a reduced diameter rear portion 32. The diameter of 
the rear portion 32 is sufficient to allow it to be slidably received 
within the central bore 14 of the outer sleeve 10. A threaded bore 33 
extends inwardly from the back end of the rear portion 32 for adjustably 
positioning the inner reamer insert 30 relative to the outer sleeve 10 (as 
explained hereinafter). The truncated conical front portion 31 has a 
plurality of circumferentially spaced longitudinal wings 34 separated by 
recesses or flutes 35 extending rearwardly from the forward end. The 
preferred inner reamer insert 30 has four wings 34, but may have anywhere 
from two to six. As seen from the front (FIGS. 7 and 11), the longitudinal 
wings 34 extend laterally from the horizontal and vertical axes X and Y. 
The exterior of each wing 34 tapers rearwardly and outwardly from the front 
end at an angle relative to the longitudinal axis, then straight reawardly 
and the back ends of the wings extend radially inward to the reduced 
diameter portion 32. The curved outer surfaces at the forward end of the 
wings 34 form a segmented conical reaming surface 36 for reaming the 
interior diameter of a pipe or conduit. The straight rearward portion of 
the wings 34 provide clearance for the thread chaser of the threading 
machine, while the outer projections 18 pass between the chasers. The 
conical reaming surface 36 preferably slopes at an angle of from 
10.degree. to 15.degree. relative to the longitudinal axis of the inner 
reamer insert 30. 
As best seen in FIG. 11, when viewed from the front end, the wings 34 
including the conical reaming surface 36 each have diametrically opposed 
flat leading edge surfaces L and flat trailing edge surfaces T spaced 
generally parallel thereto in a clockwise direction from the leading edge 
surface. The curve of the reaming surface 36 is formed such that the 
leading edge L has a large radius r3 and terminates at the clockwise 
trailing edge T with a smaller radius r4. In other words, the conical 
reaming surface 36 is curved radially inward from the leading edge to the 
trailing edge. 
Thus, as a tubular pipe or conduit is fed into the front portion of inner 
reamer insert 30 in alignment with the longitudinal axis, the leading edge 
L of the wing reaming surfaces 36 will serve as a cutting surface to 
perform any cutting necessary to remove burrs or material which extend 
radially inward from the interior diameter prior to the reaming and 
tripping operation and the smaller radius trailing edge T will serve as 
serve as a clearance angle. 
Referring now to FIGS. 3 and 12 through 15, the inner reamer insert 30 is 
installed in the outer sleeve 10 by sliding the rear portion 32 into the 
central bore 14 of the outer sleeve 10 from the front end and positioning 
the wings 34 between the projections 18 of the outer sleeve 10 as shown in 
FIG. 3. An allen head cap screw 40 is inserted through the threaded bore 
12 at the outer sleeve rear portion 11 with its shank extending through 
the bore 15 and threadedly received in the threaded bore 33 of the rear 
portion 32 of the inner reamer insert 30 and its head engaged on the 
shoulder 13. As seen in FIGS. 14 and 15, a threaded lock-down plug 41 
having an allen wrench cavity 42 larger than the allen wrench cavity of 
the cap screw is threadedly received in the threaded bore 12 of the outer 
sleeve 10. 
The cap screw can be rotated by inserting an allen wrench into the socket 
of the lock-down plug 41 and backing it off a few turns and then inserting 
a smaller allen wrench through the socket of the lock-down plug and into 
the socket of the cap screw and rotating it to drive the inner reamer 
insert 30 forward or backward on the threaded shank of the cap screw. When 
the cap screw 40 is rotated, the inner reamer insert 30 moves 
longitudinally on the threaded shank of the cap screw and the insert 30 is 
prevented from rotating since the side surfaces of the wings 34 will 
engage the projections 18. After the inner reamer insert 30 is properly 
positioned, the lock-down plug is then rotated to engage the head 43 of 
the cap screw 40 and prevent rotation of the cap screw. Thus by rotating 
the cap screw 40, the forward end of the inner reamer insert 30 can be 
selectively positioned inward or outward relative to the projections 18 of 
the outer sleeve 10. 
As best seen in FIGS. 12 and 13, when the inner reamer insert 30 is 
properly installed in the outer sleeve 10, the wings 34 are disposed 
between the projections 18 and the reaming surfaces 19 and 36 are 
circumferentially spaced in an alternating pattern. When viewed from the 
side, each rearwardly and outwardly extending wing 34 overlaps the 
adjacent shoulder 20 of the outer sleeve 10 and the adjacent angled 
surfaces 36 and 19 form an inwardly extending, flat-bottom, V-shaped 
groove G with the trip shoulder 20 forming the bottom of the groove. The 
inwardly curved reaming surface 36 of the inner reamer insert forms the 
inner side of the V-shape, the trip shoulder 20 forms the bottom, and the 
reaming surface 19 of the outer sleeve 10 forms the outer side of the 
V-shape. 
The relative angles of the reaming surface 19, the trip shoulder 20, and 
the reaming surface 36 are such that as the pipe or conduit is fed onto 
the reamer, the forward end of the truncated conical portion 31 will 
receive the end of the pipe or conduit and continued feeding will cause 
contact of the interior and exterior diameters at the end of the pipe or 
conduit to contact the converging sides (leading edge L) of the V-shaped 
groove G sufficient to simultaneously ream the interior and exterior 
diameters. Continued feeding of the pipe or conduit will cause its 
exterior diameter to forceably contact the reaming surface 18 near its 
intersection with the trip shoulder 20 (near the trailing edge T) 
sufficient to activate the trip mechanism of the die head. The transverse 
angle of the trip shoulder 20 is sufficient to provide smooth contact with 
the end surface of the pipe or conduit and prevent galling. 
Since the curved reaming surfaces 36 are curved radially inward from the 
leading edge to the trailing edge and the flat reaming surfaces 19 extend 
outwardly from the leading edge to the trailing edge, the flat-bottom 
V-shaped groove G is wider at the clockwise trailing edge than at the 
leading edge. This flat-bottom V-shaped groove configuration provides 
minimum pipe contact area while allowing the exterior and interior 
diameter of the pipe or conduit to forceably contact the reaming surfaces 
somewhere near the trailing edges and the raised trailing surface of the 
trip shoulder 20 provides smooth contact with the end of the pipe or 
conduit to prevent galling. 
By adjusting the inner reamer insert 30 relative to the outer sleeve 10, 
the width of the flat-bottom, V-shaped groove G can be varied to fit pipe 
or conduit having different wall thicknesses. 
ANOTHER EMBODIMENT 
Referring now to FIGS. 16 through 20, there is shown another embodiment of 
the adjustable chamfering reamer R2, which is used for larger diameter 
pipe or conduit. As with the previously described embodiment, the 
adjustable chamfering reamer R2 is capable of chamfering both the outside 
and inside diameters of a pipe or conduit simultaneously, and is 
adjustable to receive pipe or conduit of various wall thicknesses. The 
reamer R2 has a cylindrical outer sleeve 50 and an adjustable inner reamer 
insert 60 which is longitudinally adjustable relative to the outer sleeve. 
The cylindrical outer sleeve 50 has a reduced diameter tailpiece 51 at its 
rearward end. A first threaded bore 52 extends inwardly from the rear end 
of the tailpiece 51 to receive the clamping rod accessory of the threading 
machine. A central bore 53 extends inwardly from the forward end and 
terminates in a second smaller diameter threaded bore 54 defining a 
shoulder 55 therebetween. The outer diameter of the outer sleeve 50 is of 
sufficient size to be received in the bore of the die head of the 
threading machine. 
The forward end of the outer sleeve 50 has a plurality of circumferentially 
spaced cut-away portions 56 extending rearwardly to define a plurality of 
projections 57. As previously described with reference to FIG. 4, the 
preferred outer sleeve 50 has four projections 57 extending laterally from 
the horizontal and vertical axes X and Y, but may have anywhere from two 
to six. The interior surface at the front end of each projection 57 
extends angularly rearward and inwardly relative to the longitudinal axis 
of the outer sleeve to form a reaming surface 58 which terminates in a 
trip shoulder 59 that extends radially inward to the central bore 53. The 
preferred angle of the reaming surface 58 is from 20.degree. to 30.degree. 
relative to the longitudinal axis. The diametrical distance between the 
outer ends of the reaming surfaces 58 is greater than the exterior 
diameter of the pipe or conduit being reamed and the inner end of the 
reaming surface where it joins the shoulder 59 is smaller than the 
exterior diameter of the pipe or conduit. 
As shown in FIG. 18, when viewed from the front end, the projections 57 
each have diametrically opposed flat leading edge surfaces L and flat 
trailing edge surfaces T spaced generally parallel thereto in a clockwise 
direction from the leading edge surface. The forwardmost end surface of 
the projections are curved on a radius r5 and the reaming surfaces 58 
extend clockwise from the X and Y axes. The inner end of the reaming 
surface 58 where it joins the trip shoulder 59 is curved such that the 
leading edge L has a large radius r6 and terminates at the clockwise 
trailing edge T with a smaller radius r7. In other words, the inner end of 
the conical reaming surface 58 where it joins the trip shoulder 59 is 
curved radially inward from the leading edge to the trailing edge. Thus, 
the inwardly tapered reaming surface 58 is wider at the trailing edge T 
than at the leading edge L. As seen in FIG. 17, the trip shoulder 59 
slopes upwardly toward the front of the outer sleeve 50 at an angle A1 
from the leading edge L to the trailing edge T to form an angled tripping 
surface transverse to the longitudinal axis. The preferred angle A1 is 
from approximately 1.degree. to 3.degree.. 
As a tubular pipe or conduit is fed into the front portion of the outer 
sleeve 50 in alignment with the longitudinal axis, the leading edge L of 
the reaming surfaces 58 serve as a cutting surface to perform any cutting 
necessary to remove burrs or material which extend radially outward from 
the exterior diameter, and as the pipe or conduit continues to be fed onto 
the reaming surfaces 58, the exterior diameter will contact the inwardly 
angled reaming surface 58 somewhere near the trailing edge since the 
trailing edge T is wider than the leading edge L. Thus, the reaming 
surfaces 58 provide an angled cutting surface with minimum pipe contact 
area and a smooth reaming surface for chamfering the exterior diameter. 
Continued longitudinal feeding of the pipe or conduit onto the reaming 
surfaces will cause its interior diameter to contact the reaming surface 
at its approximate transition with the trip shoulder 59 near the trailing 
edge T to apply the tripping force necessary to activate the tripping 
mechanism, and the angled trip shoulder 59 provides a raised trailing 
surface to prevent galling. 
Referring now to FIGS. 16, 19, and 20, the adjustable inner reamer insert 
60 is a generally cylindrical member having a truncated conical front 
portion 61 and a reduced diameter rear portion 62. The diameter of the 
rear portion 62 is sufficient to allow it to be slidably received within 
the central bore 53 of the outer sleeve 50. A central bore 63 extends 
inwardly from the front end of the inner reamer insert 60 and terminates 
in a reduced diameter bore 64 defining a shoulder 65 therebetween. The 
truncated conical front portion 61 has a plurality of circumferentially 
spaced longitudinal wings 66 separated by recesses or flutes 67 extending 
rearwardly from the forward end. The preferred inner reamer insert 60 has 
four wings 66, but may have anywhere from two to six. 
The details of the wings and reaming surfaces of the inner reamer insert 60 
are the same as previously shown and described with reference to FIGS. 11, 
12, and 13, and will not be described in detail to avoid repetition. As 
previously shown and described with reference to FIG. 11, the longitudinal 
wings 66 extend laterally from the horizontal and vertical axes X and Y. 
The exterior of each wing 66 tapers rearwardly and outwardly from the front 
end at an angle relative to the longitudinal axis, then straight reawardly 
and the back ends of the wings extend radially inward to the reduced 
diameter portion 62. The curved outer surfaces at the forward end of the 
wings 66 form a segmented conical reaming surface 68 for reaming the 
interior diameter of a pipe or conduit. The straight rearward portion of 
the wings 66 provide clearance for the thread chaser of the threading 
machine while the projections 57 pass between the chasers. The conical 
reaming surface 68 preferably slopes at an angle of from 10.degree. to 
15.degree. relative to the longitudinal axis of the inner reamer insert 
60. 
As previously described with reference to FIG. 11, when viewed from the 
front end, the wings 66 including the conical reaming surface 68 each have 
diametrically opposed flat leading edge surfaces L and flat trailing edge 
surfaces T spaced generally parallel thereto in a clockwise direction from 
the leading edge surface. The curve of the reaming surface 68 is formed 
such that the leading edge L has a large radius and terminates at the 
clockwise trailing edge T with a smaller radius. In other words, the 
conical reaming surface 68 is curved radially inward from the leading edge 
to the trailing edge. 
Thus, as a tubular pipe or conduit is fed into the front portion of inner 
reamer insert 60 in alignment with the longitudinal axis, the leading edge 
L of the wing reaming surfaces 68 will serve as a cutting surface to 
perform any cutting necessary to remove burrs or material which extend 
radially inward from the interior diameter prior to the reaming and 
tripping operation and the smaller radius trailing edge T will serve as 
serve as a clearance angle. 
Referring now to FIG. 20, the inner reamer insert 60 is installed in the 
outer sleeve 50 by sliding the rear portion 62 into the central bore 53 of 
the outer sleeve 50 from the front end and positioning the wings 66 
between the projections 57 of the outer sleeve 50. An allen head cap screw 
70 is inserted through the central bore 63 of the inner reamer insert 60 
with its shank 71 extending through the reduced bore 64 and threadedly 
received in the threaded bore 54 of the outer sleeve 50. 
One or more thin disc-shaped shims or spacers 73 may be installed between 
the rear end of the inner reamer insert 60 and the shoulder 55 of the 
outer sleeve 50 to position the inner reamer insert forward relative to 
the outer sleeve. The shims or spacers 73 may be removed to retract the 
inner reamer insert relative to outer sleeve, such that the forward end of 
the inner reamer insert can be selectively positioned inward or outward 
relative to the outer sleeve projections. 
When the inner reamer insert 60 is properly installed in the outer sleeve 
50, the wings 66 are disposed between the projections 58 and the reaming 
surfaces 59 and 68 are circumferentially spaced in an alternating pattern. 
When viewed from the side, each rearwardly and outwardly extending wing 66 
overlaps the adjacent shoulder 59 of the outer sleeve 50 and the adjacent 
angled surfaces 68 and 58 form an inwardly extending, flat-bottom, 
V-shaped groove G with the trip shoulder 59 forming the bottom of the 
groove. The inwardly curved reaming surface 68 of the inner reamer insert 
forms the inner side of the V-shape, the trip shoulder 59 forms the 
bottom, and the reaming surface 58 of the outer sleeve 50 forms the outer 
side of the V-shape. 
The relative angles of the reaming surface 58, the trip shoulder 59, and 
the reaming surface 68 are such that as the pipe or conduit is fed onto 
the reamer, the forward end of the truncated conical portion 61 will 
receive the end the pipe or conduit and continued feeding will cause 
contact of the interior and exterior diameters at the end of the pipe or 
conduit to contact the converging sides (leading edge L) of the V-shaped 
groove G sufficient to simultaneously ream the interior and exterior 
diameters. Continued feeding of the pipe or conduit will cause its 
exterior diameter to forceably contact the reaming surface 58 near its 
intersection with the trip shoulder 59 (near the trailing edge T) 
sufficient to activate the trip mechanism of the die head. The transverse 
angle of the trip shoulder 59 is sufficient to provide smooth contact with 
the end surface of the pipe or conduit and prevent galling. 
Since the curved reaming surfaces 68 are curved radially inward from the 
leading edge to the trailing edge and the inwardly tapered reaming 
surfaces 59 are wider at the trailing edge, the flat-bottom V-shaped 
groove G provides minimum pipe contact area while allowing the exterior 
and interior diameter of the pipe or conduit to forceably contact the 
reaming surfaces somewhere near the trailing edges and the raised trailing 
surface of the trip shoulder 59 provides smooth contact with the end of 
the pipe or conduit to prevent galling. 
By adjusting the inner reamer insert 60 relative to the outer sleeve 50, 
the width of the flat-bottom, V-shaped groove G can be varied to fit pipe 
or conduit having different wall thicknesses. 
The present adjustable reamer R or R2 can also be quickly and easily 
adjusted to compensate for wear of the cutting and reaming surfaces by 
positioning the inner reamer insert relative to the outer sleeve. The 
cutting and reaming surfaces can also be renewed by removing the inner 
reamer insert from the outer sleeve and re-grinding the surfaces as 
necessary or simply replacing either of the worn members. 
While this invention has been described fully and completely with special 
emphasis upon a preferred embodiment, it should be understood that within 
the scope of the appended claims the invention may be practiced otherwise 
than as specifically described herein.