US1835245A - Conduit and method of making the same - Google Patents

Conduit and method of making the same Download PDF

Info

Publication number
US1835245A
US1835245A US427824A US42782430A US1835245A US 1835245 A US1835245 A US 1835245A US 427824 A US427824 A US 427824A US 42782430 A US42782430 A US 42782430A US 1835245 A US1835245 A US 1835245A
Authority
US
United States
Prior art keywords
section
sections
junction
duct
conduit
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US427824A
Inventor
Roy A Shipley
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NAT FIREPROOEING CORP
NATIONAL FIREPROOEING Corp
Original Assignee
NAT FIREPROOEING CORP
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by NAT FIREPROOEING CORP filed Critical NAT FIREPROOEING CORP
Priority to US427824A priority Critical patent/US1835245A/en
Application granted granted Critical
Publication of US1835245A publication Critical patent/US1835245A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02GINSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
    • H02G3/00Installations of electric cables or lines or protective tubing therefor in or on buildings, equivalent structures or vehicles
    • H02G3/02Details
    • H02G3/06Joints for connecting lengths of protective tubing or channels, to each other or to casings, e.g. to distribution boxes; Ensuring electrical continuity in the joint
    • H02G3/0608Joints for connecting non cylindrical conduits, e.g. channels

Definitions

  • Figure 1 is aside elevation of;a:-standard sixductextrudedaconduit sectiomof uniform,
  • - Figure'2 is :atop' lan viewof the-same showingthe upper en s ofthecuttingplanes; i Figurefi-is a side elevation showing the i outer-sections of :Fdgure l-aftercutting;
  • Figure 4 is atop-plan view ofz'the left-hand section'of Figural);
  • Figureifi is arlongitudinal section taken on the .line FYI-A 1- of Figure 8-;
  • Figure 7 is a top plan view ofithe; structure i of Eigureo;
  • Figures .lOand 11 are views showing-the method ofcutting for a'ca'sewhere three separate.conduits lead from the @junction box;
  • Figure 12 a view similar:to : Figure 9 showing inv place a junction section joining a single multi-duct conduit and three separate conduits.
  • : Figure 1 represents a-standard six- 60 duct conduit sectionformedof fgreen clay or other ceramic material which has been extruded in the ordinary .process.
  • this section 'the ducts are parallel and a cross section is substantially uniform.
  • the material is more plastic and workable.
  • Such a section is placed on a suitable base or support and cut longitudinally oirthe lines indicated at A and B in Figures 1 and 2, this being preferably done by a wire cutter pushed lengthwise through the material and guided in any suitable way, as by a frame, along the edge of which the Wire slides.
  • a skeleton box or frame is then preferably slid downwardly over the sections to press the cut' and roughened surfaces ofportions 4 and 5 firmly together.
  • a mandrel is then preferably inserted in a duct and a swab pushed down through the adjacent ducts to press the webs together and insure solidwebs and also to preserve the proper shapeofthe ducts.
  • the pressing box is preferably slightly shorter than the length of the section and after the pressing and swabbing, the upper end of the tile is cut off transversely ,andthe box removed.
  • the side seams 9 are then scored out from the exterior andthe'longitudinal grooves thus formed filled with soft clay and smoothed down with a knife.
  • Dowel-pinholes 6 are'then formed in "the outside ends of the junction section, a guide beingused if necessary to insure proper ositioning. The ends of the respective ucts being of less importance.
  • Figures 10 a-nd 11 illustrate the making of are then reamed or chamfcred, as shown at 7, slots 8 are preferably left or provided in the lower portion of the junction section between the webs to permit air to enter and assist in drying and the ends are preferably scratched or roughened. The section is then burned in the usual way to form the completed article.
  • Figure 9 shows a junction section 10 in' place-in a conduit and'j oining a single multi duct section 11 with a pair of sections 12.
  • the thickness of the central web at one end of the junction section is substantially equal to the thickness of the central web of the standard multi-duct section 11, and the thickness of the central Web of'the junction section 10 at the opposite end is somewhat greater than twice the thickness of a standard outside wall.
  • a standard outside wall is of greater thickness than a standard inside Web.
  • section 2 is cut as shown in Figures 1 and 3 so that the inside web of the junction section will be somewhat thicker at the lower end than twice the thickness of a'standard outside wall.
  • the cuts C and D preferably start midway of analogous t the twocross webs of the section 14,and
  • the cuts E and F of the section 15 of Figure 11 preferably start midway of the two cross webs and thence diverge toward the bot- *tom of the section, passing into the outer.
  • the junction section 22 is shown in place in a conduit between a standard three-duct section 23 and three standard single-duct sections 24, 25 and 26.
  • the connections between the junction section and thestandard sections are made similarlyito the connections shown in Figure 9.
  • Thejunction' section'shown in the drawings has its lower extremity ( Figures 5 and 6) somewhat pointed, which causes a slight; divergence of the sections connected therewith such as'the divergence of the sections 12 in Figure 9;
  • the junction section as completed is in substantial accordance with Figures 6 and 9, but on account of the fact that the green clay while being formed into the junction section is resting on the lower end, as shown in Figures 5'and 6, there is a tendency for the'lower surface of the junction sectionto flattenout and be come generally parallel to the cut-ofi-upper surface. Probably in most cases-the actual result will be somewhat between the theoretical showing of Figure 9' and a junction section having parallel end faces.
  • junction section takes upon completion is not of great importance because the divergence of the standard sections immediately adjacent the junction section is not necessary. In most cases the actual divergence desired is obtained by slant sections of well known standard"construction, and- 7 separation of the standard sections immediately adjacent the junction section'is not relied on. However, asshown in Figures 9 and 12, it is possible to obtain such-a diver gence if desired; r 7
  • my improved junction conduit is made of two or more separately formed and separate pieces or sections which" are united and burned together. Also that the ducts are substantially straight from end to end and without internal strains; alsothat the internal web at one end is of normal th'icin f' ness and at the other end'is atyleasttwice normal web thickness and preferably slightly more than this, to allow for imperfections,
  • the axes of the conduits are preferably straight, but diverge from one end toward the other, and at one end the section fits the normal multi-duct section,"
  • a our-duct junction box is made out of a six-duct standard extruded section, but it will be understood that connecting or junction sections of various sizes may be cut from standard sections of various sizes and shapes.
  • the four-duct connecting section shown may obviously be made out of two four-duct standard sections.
  • two standard sections may be cut up to provide a three-111 connection.
  • Standard single-duct sections may be used for making a junction section for connecting standard single-duct sections with a standard multi-duct section or for making other types of junction sections.
  • junction sections It is preferred to utilize only standard extruded sections in the making of the junction sections. This greatly reduces the cost of the junction sections, as it obviates the necessity of providing special extrusion dies. However, if desired, special sections may be extruded for making the junction sections, such sections being cut and joined as herein disclosed.
  • the dividing web or wall between each pair of ducts is of gradually increasing thickness, and is formed of portions of the webs of two independently formed sections which are fastened together by burning or otherwise.
  • junction or connecting section and in the article itself, which may be made from two, three or more separately formed duct pieces.
  • a junction section for multi-duct conduits consisting of a plurality of separately formed duct sections burned together.
  • a junction section for multi-duct conduits consisting of a plurality of separately formed duct sections burned together, the sections having a web between them of increasing thickness.
  • a junction section for multi-duct conduits consisting of a plurality of separately formed duct sections burned together, the sections having a two-layer separating wall of normal web thickness at one end and increasing in thickness toward the other end.
  • a junction section for multi-duct conduits consisting of a plurality of separately formed duct sections burned together, the sections having a separating web wall thinner at one end than the other.
  • a junction or multi-duct conduit section consisting of a plurality of separately formed sections burned together, at least one section having a wall thinner at one end than at the other.
  • a junction or connecting section-for multi-duct conduits consistingiof a plurality ofv separately formed sections burned ;.to' gether, at i'least one of said'seetions having: a connecting web portion with. arthinned down portion, the total. connecting web being :of normal thickness atone end and. of abnormal thickness at the other.
  • aiunitary junction section for mrilti-ductconduits comprised of-a plurality-of separately formed duct sections.
  • aunitary-junction section for multi-ductconduits comprised of a plurality of separately formed duet sections'at least one of which has-awe'b of uneven thickness.
  • means for connecting a conduit with a plurality of conduits extending therefrom comprising a ceramic member having ducts whose axes are substantially straight from end to end and non-parallel.
  • means for connecting a conduit with a plurality of conduits extending therefrom comprising a unitarily burned ceramic member having ducts whose axes are substantially straight from end to end and non-parallel.
  • means for connecting a conduit with a plurality of conduits extending therefrom comprising a ceramic member comprising a plurality of longitudinally extending sections joined together while green, such member having a plurality of longitudinally extending non-parallel ducts.
  • means for connecting a conduit with a plurality of conduits extending therefrom comprising a ceramic member comprising a plurality of separate longitudinally extending sections integrally joined, said member having longitudinally extending non-parallel ducts.
  • a method of making a conduit section comprising providing a standard conduit section of generally constant cross section,
  • a method of making a conduit section comprising providing a. standard conduit section, removing therefrom an interior layer, and connecting together the remaining layers to form a conduit section.
  • V 18 A method of making a ceramic conduit section, comprising providing a green standard conduit section, cutting out a portion thereof so as to leave a plurality of-nortions, connecting together the remaining portions, and burning such connected portions to form a ceramic conduit section.
  • a method of making a conduit section comprising cutting angularly through at leastone Web of at least one standard conduit section to produce at least two partial sections having tapered Webs, and joining together such partial sections in such manner as to produce a conduit section of non-uniform cross-section.
  • a method of making'a conduit section comprising providing at least tvvo longitudinally extending portions at least one of Which has a tapered Wall, and connecting to gether such portions at such tapered Wall:

Landscapes

  • Engineering & Computer Science (AREA)
  • Architecture (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Rigid Pipes And Flexible Pipes (AREA)

Description

Dec. 8, 1931. R. A. SHIPLEY 1,835,245
CONDUIT AND METHOD OF MAKING THE SAME Filed Feb. 12, 1930 2-Sheets-Sheet 1 Dec. 8, 1931. R. A. SHIPLEY CONDUIT AND METHOD OF MAKING THE SAME 2 Sheets-Sheet 2 Filed Feb. 12, 1950 MN r/I /flZf/I A Qs\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\sk\ Hr!!! Patented Dec. 8, 1931 nmrsn STATES PATENT OFFICE R! .A..SHIIELEY, 16F PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO NATIONAL FIRE- ."PR-QOEING GOBPORATION, 0]? PITTSBURGH, .BENNSYLVANIA, A CORPORATION OF .BENNSYLITANIA GOND'UIT AND 'METHOIJ OF MAKING THE .SAME
Application tiled l'ebr'uary -12, 1930. Serial No. 427,824.
also relates to :an improved method of makin :such a junctionsection or sections.
Tn the drawings which. showcertain forms of :my invention: t
:Figure 1 is aside elevation of;a:-standard sixductextrudedaconduit sectiomof uniform,
cross :section throughout, :showing in 'dotted lines :thecutting zplanes;
-Figure'2 is :atop' lan viewof the-same showingthe upper en s ofthecuttingplanes; iFigurefi-is a side elevation showing the i outer-sections of :Fdgure l-aftercutting;
Figure 4, is atop-plan view ofz'the left-hand section'of Figural);
:Figure 5'isa-side elevation showing the sections of Figure -3 assembled and -.pressed 'together, and after grooves .have been scored therein; 7 I
Figureifi is arlongitudinal section taken on the .line FYI-A 1- of Figure 8-;
Figure 7 is a top plan view ofithe; structure i of Eigureo;
,F gureS isabottom plan'view of-thefinished section Figure-9 is a cross-sectional assembly view showing [the afinished junction section in place;
Figures .lOand 11 are views showing-the method ofcutting for a'ca'sewhere three separate.conduits lead from the @junction box; and
Figure 12 a .view similar:to :Figure 9 showing inv place a junction section joining a single multi-duct conduit and three separate conduits.
In :Figure 1, 2 represents a-standard six- 60 duct conduit sectionformedof fgreen clay or other ceramic material which has been extruded in the ordinary .process. In this section,'the ducts are parallel and a cross section is substantially uniform. In the green form, the material is more plastic and workable. Such a section is placed on a suitable base or support and cut longitudinally oirthe lines indicated at A and B in Figures 1 and 2, this being preferably done by a wire cutter pushed lengthwise through the material and guided in any suitable way, as by a frame, along the edge of which the Wire slides. These 'cuts preferably start midway of the two cross webs of thiss'ix-duct conduit, and thence converge toward each other, finally passing'into the middleducts through their webs a short distance above the bottom of'the section. The central portion 3 is then removedand discarded, leaving the outer-sections, as shown'inFigures 3 and 4. The inner longitudinal cut surfaces of the outer portions 4 and 5 are scratchedorroughened-and are then preferably coated with a bonding material, preferably of the same nature and plastic consistency as the section, and the two sections are then pressed togetherinto contact along the cut and roughened surfaces. This maybe carried out'byhand with the sections resting on a suitable support-"and a skeleton box or frame is then preferably slid downwardly over the sections to press the cut' and roughened surfaces ofportions 4 and 5 firmly together. A mandrel is then preferably inserted in a duct and a swab pushed down through the adjacent ducts to press the webs together and insure solidwebs and also to preserve the proper shapeofthe ducts.
The pressing box is preferably slightly shorter than the length of the section and after the pressing and swabbing, the upper end of the tile is cut off transversely ,andthe box removed. The side seams 9 are then scored out from the exterior andthe'longitudinal grooves thus formed filled with soft clay and smoothed down with a knife.
Dowel-pinholes 6 are'then formed in "the outside ends of the junction section, a guide beingused if necessary to insure proper ositioning. The ends of the respective ucts being of less importance. Figures 10 a-nd 11 illustrate the making of are then reamed or chamfcred, as shown at 7, slots 8 are preferably left or provided in the lower portion of the junction section between the webs to permit air to enter and assist in drying and the ends are preferably scratched or roughened. The section is then burned in the usual way to form the completed article.
Figure 9 shows a junction section 10 in' place-in a conduit and'j oining a single multi duct section 11 with a pair of sections 12. The thickness of the central web at one end of the junction section is substantially equal to the thickness of the central web of the standard multi-duct section 11, and the thickness of the central Web of'the junction section 10 at the opposite end is somewhat greater than twice the thickness of a standard outside wall.
A standard outside wall is of greater thickness than a standard inside Web. Hence the section 2 is cut as shown in Figures 1 and 3 so that the inside web of the junction section will be somewhat thicker at the lower end than twice the thickness of a'standard outside wall.
This relation is clearly shown in Figure 9. The outside edges of the standard sec tions 12 are shown slightly spaced from each other at the junction with the section 10. This slight additional space permits of the insertion of mortar 13 between the sections 12 adjacent the junction section to positively connect together and properlyspace the sections 12 and to allow for imperfections in construction. It is important that the inner duct walls match up as closely as possible. at
thejoint,v the matching of the outer walls a junction section in which a three-ductsect on 1s connected to three one-duct sections.
In this case, it is necessary touse two piecesof standard three-ways to make the junction condult, as one cutis .taken from the center of a tile and the other two pieces taken from the outside of another section. I I In makmg a section. for, connecting together a three-duct sectlon and three one-.
duct sections, two standard three-duct sections 14, (Figure 10) and (Figure 11) are used. Thevsection 14 is cut longitudinally on the linesindicated at C and D inFigurelO,
and'the section 15 is cut longitudinally on the lines indicated at E and F in Figure 11.
The cuts C and D preferably start midway of analogous t the twocross webs of the section 14,and
thence converge toward each other, finally passing into the middle duct through its webs,
a short distance above the bottom of the sec- 7 tion. The cutting of the section 14 is exactly o the cutting of the section 2 of Flgure 1.
The cuts E and F of the section 15 of Figure 11 preferably start midway of the two cross webs and thence diverge toward the bot- *tom of the section, passing into the outer.
ducts through their webs a short distance above the bottom. After the sections 14 and 15 have been cut as described, the portions 17 i In Figure 12 the junction section 22 is shown in place in a conduit between a standard three-duct section 23 and three standard single- duct sections 24, 25 and 26. The connections between the junction section and thestandard sections are made similarlyito the connections shown in Figure 9.
Thejunction' section'shown in the drawings has its lower extremity (Figures 5 and 6) somewhat pointed, which causes a slight; divergence of the sections connected therewith such as'the divergence of the sections 12 in Figure 9; Theoretically the junction section as completed is in substantial accordance with Figures 6 and 9, but on account of the fact that the green clay while being formed into the junction section is resting on the lower end, as shown in Figures 5'and 6, there is a tendency for the'lower surface of the junction sectionto flattenout and be come generally parallel to the cut-ofi-upper surface. Probably in most cases-the actual result will be somewhat between the theoretical showing of Figure 9' and a junction section having parallel end faces. The actual form which the junction section takes upon completion is not of great importance because the divergence of the standard sections immediately adjacent the junction section is not necessary. In most cases the actual divergence desired is obtained by slant sections of well known standard"construction, and- 7 separation of the standard sections immediately adjacent the junction section'is not relied on. However, asshown in Figures 9 and 12, it is possible to obtain such-a diver gence if desired; r 7
It will be observed that my improved junction conduit is made of two or more separately formed and separate pieces or sections which" are united and burned together. Also that the ducts are substantially straight from end to end and without internal strains; alsothat the internal web at one end is of normal th'icin f' ness and at the other end'is atyleasttwice normal web thickness and preferably slightly more than this, to allow for imperfections,
easy joining and any slight separati'ngma:
terial at this point where the separate con-" duitsibranch oft. The axes of the conduits are preferably straight, but diverge from one end toward the other, and at one end the section fits the normal multi-duct section,"
while at the other end it provides for the proper web thickness for joining the two or more branchin sections.
As shown, a our-duct junction box is made out of a six-duct standard extruded section, but it will be understood that connecting or junction sections of various sizes may be cut from standard sections of various sizes and shapes. For example, the four-duct connecting section shown may obviously be made out of two four-duct standard sections. As shown in the later figures, two standard sections may be cut up to provide a three-111 connection. Standard single-duct sections may be used for making a junction section for connecting standard single-duct sections with a standard multi-duct section or for making other types of junction sections.
It is preferred to utilize only standard extruded sections in the making of the junction sections. This greatly reduces the cost of the junction sections, as it obviates the necessity of providing special extrusion dies. However, if desired, special sections may be extruded for making the junction sections, such sections being cut and joined as herein disclosed.
It will be noted that in the final junction section, the dividing web or wall between each pair of ducts is of gradually increasing thickness, and is formed of portions of the webs of two independently formed sections which are fastened together by burning or otherwise.
Many variations may be made in the method of making the junction or connecting section and in the article itself, which may be made from two, three or more separately formed duct pieces.
I claim:
1. A junction section for multi-duct conduits consisting of a plurality of separately formed duct sections burned together.
2. A junction section for multi-duct conduits consisting of a plurality of separately formed duct sections burned together, the sections having a web between them of increasing thickness.
3. A junction section for multi-duct conduits consisting of a plurality of separately formed duct sections burned together, the sections having a two-layer separating wall of normal web thickness at one end and increasing in thickness toward the other end.
4. A junction section for multi-duct conduits consisting of a plurality of separately formed duct sections burned together, the sections having a separating web wall thinner at one end than the other.
5. A junction or multi-duct conduit section consisting of a plurality of separately formed sections burned together, at least one section having a wall thinner at one end than at the other.
6. A junction section for multi-duct conduits'. having an increasing crosssection'from one =end :to the other, the separating web beingthinned downat one end.
7.;Ajnnction orxconnecting section for multi-duct conduits consisting of a plurality of separately formed sections burned together, atleast one of said-sectionshaving a connecting web portion with a thinned downportion.
'8. A junction or connecting section-for multi-duct conduits consistingiof a plurality ofv separately formed sections burned ;.to' gether, at i'least one of said'seetions having: a connecting web portion with. arthinned down portion, the total. connecting web being :of normal thickness atone end and. of abnormal thickness at the other.
:9. As: an article of manufacture, aiunitary junction section for mrilti-ductconduits comprised of-a plurality-of separately formed duct sections.
.10. .As an article of manufacture, aunitary-junction section for multi-ductconduits comprised of a plurality of separately formed duet sections'at least one of which has-awe'b of uneven thickness.
:11. As a manufacturepmeans 'forconnectingaconduit with a plural ty of conduits extending therefrom comprising a "member havingduets whose axes are substantially straight from end to end and noneparallel, the distance bet-ween adjacent'walls of such ducts being at least substantially .twice "as great at-one end of .the member as at the other end.
12. As a manufacture, means for connecting a conduit with a plurality of conduits extending therefrom comprising a ceramic member having ducts whose axes are substantially straight from end to end and non-parallel.
13. As a manufacture, means for connecting a conduit with a plurality of conduits extending therefrom comprising a unitarily burned ceramic member having ducts whose axes are substantially straight from end to end and non-parallel.
14. As a manufacture, means for connecting a conduit with a plurality of conduits extending therefrom comprising a ceramic member comprising a plurality of longitudinally extending sections joined together while green, such member having a plurality of longitudinally extending non-parallel ducts.
15. As a manufacture, means for connecting a conduit with a plurality of conduits extending therefrom comprising a ceramic member comprising a plurality of separate longitudinally extending sections integrally joined, said member having longitudinally extending non-parallel ducts.
16. A method of making a conduit section, comprising providing a standard conduit section of generally constant cross section,
removing from such standard conduit section a longitudinally extending portion so as to leave a plurality of portions,and con neoting together the remaining portions;
171 A method of making a conduit section, comprising providing a. standard conduit section, removing therefrom an interior layer, and connecting together the remaining layers to form a conduit section.
V 18. A method of making a ceramic conduit section, comprising providing a green standard conduit section, cutting out a portion thereof so as to leave a plurality of-nortions, connecting together the remaining portions, and burning such connected portions to form a ceramic conduit section.
19. A method of making a conduit section, comprising cutting angularly through at leastone Web of at least one standard conduit section to produce at least two partial sections having tapered Webs, and joining together such partial sections in such manner as to produce a conduit section of non-uniform cross-section.
20. A method of making'a conduit section, comprising providing at least tvvo longitudinally extending portions at least one of Which has a tapered Wall, and connecting to gether such portions at such tapered Wall:
.to form a conduit section of non-uniform cross-section. I
my hand.
ROY A. SHIPLEY;
US427824A 1930-02-12 1930-02-12 Conduit and method of making the same Expired - Lifetime US1835245A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US427824A US1835245A (en) 1930-02-12 1930-02-12 Conduit and method of making the same

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US427824A US1835245A (en) 1930-02-12 1930-02-12 Conduit and method of making the same

Publications (1)

Publication Number Publication Date
US1835245A true US1835245A (en) 1931-12-08

Family

ID=23696441

Family Applications (1)

Application Number Title Priority Date Filing Date
US427824A Expired - Lifetime US1835245A (en) 1930-02-12 1930-02-12 Conduit and method of making the same

Country Status (1)

Country Link
US (1) US1835245A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3219467A (en) * 1960-09-09 1965-11-23 Johns Manville Manufacture of asbestos-cement products
US4342475A (en) * 1980-04-03 1982-08-03 Midwest Plastic Fabricators, Inc. Connector and adapter for duct systems for telephone cables and the like
US5437087A (en) * 1993-08-03 1995-08-01 Bell Atlantic Network Services, Inc. Method of attaching an interduct to aduct

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3219467A (en) * 1960-09-09 1965-11-23 Johns Manville Manufacture of asbestos-cement products
US4342475A (en) * 1980-04-03 1982-08-03 Midwest Plastic Fabricators, Inc. Connector and adapter for duct systems for telephone cables and the like
US5437087A (en) * 1993-08-03 1995-08-01 Bell Atlantic Network Services, Inc. Method of attaching an interduct to aduct

Similar Documents

Publication Publication Date Title
US2246987A (en) Continuous molding apparatus
US2926729A (en) Process to embody wooden laths with coating of plastic material
US1778333A (en) Manufacture of lumber
DK143492B (en) APPARATUS FOR THE PREPARATION OF RIBBEROES WITH A smooth inside
US1835245A (en) Conduit and method of making the same
US2230309A (en) Ceramic product
US1578250A (en) Process of making plaster board
US3884749A (en) Machine for the manufacture of wood fibre panels in continuous lengths
US600856A (en) Sebastian g
US2209643A (en) Method and means of forming brick and tile
US2267817A (en) Pipe fitting of felted asbestos and cement
US1668782A (en) Method of making rubber bladders
US287699A (en) meekee
US833382A (en) Art of manufacturing cleats for barrels.
JP2611897B2 (en) Flat roof tile manufacturing method
US1092882A (en) Die.
US1503665A (en) Method of and apparatus for making annular sheets of rubber
US1310442A (en) roberts
US1558018A (en) Apparatus for making cushion tires
US1092881A (en) Art of manufacturing combs.
US901772A (en) Process of cutting sheet metal.
US1984525A (en) Method of securing an increased yield of welting from leather stock
US1513590A (en) Method of and apparatus for making hollow brick
US1289492A (en) Roofing-tile.
US1968447A (en) Underground conduit