US3501129A

US3501129A - Bundle conductor stringingsagging block

Info

Publication number: US3501129A
Application number: US689711A
Authority: US
Inventors: James B Simmonds
Original assignee: Individual
Current assignee: Individual
Priority date: 1967-12-11
Filing date: 1967-12-11
Publication date: 1970-03-17
Anticipated expiration: 1987-03-17

Description

March 17, 1-970 J. B. SIMMONDS BUNDLE CONDUCTOR STRINGING-SAGGING BLOCK 2 Sheets-Sheet 1 Filed Dec. 11, 1967 INVENTOR JAMES B. SIMMONDS 8). A YMM m film ATTORNEYS.

March 17, 1970 J. B. SIMMONDS 3,501,129

BUNDLE CONDUCTOR STRINGING-SAGGING BLOCK Filed Dec. 11. 1967 2 Sheets-Sheet 2 Fla? /0 INVENTOR JAMES B. sumo/v05 A 7 romveys.

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United States Patent US. Cl. 254-1343 8 Claims ABSTRACT OF THE DISCLOSURE Two adaptor plates are attached to each side'of a conventional yoke plate that is suspended by insulators from one arm of a wire supporting tower. Suspended from the middle of the adaptor plates is an assembly comprising a pivoting coat hanger member which releasably supports at each end a sheave subassembly. A removable wire shaft passes through horizontally mounted tubular members in each subassembly which support the respective sheaves therein, There is also a central drum mounted on said inner shaft between the subassemblies. Each subassembly also includes an inner rotatable mounting plate which is mounted about the respective tubular assembly and which is rotated to an upright position and bolted when the wires have been drawn through the assembly and rest on the sheaves. Straps of a predetermined length are pinned between each subassembly and the adaptor plates. Eventually the central drum, the coat hanger and the means by which the latter is suspended from the adaptor plates are removed. A corresponding method is also explained.

BACKGROUND OF THE INVENTION In the stringing of high voltage bundle conductors between towers, the wires are conventionally first pulled through pulley assemblies or blocks which are temporarily suspended from so-called yoke-plates that are attached to insulators on the tower arm. After the wires are resting on the pulleys they are pulled to the desired tension, this process being known as sagging the wires. Finally the pulleys are removed and the wires are transferred to permanent clamping devices attached to the insulator.

During recent years the installation of electrical power lines of very high voltage say 500,000 volts has proceeded apace. Wherever possible, for economic reasons, towers for supporting these very high voltage lines are placed in as straight at line as possible. However, because of unavoidable terrain characteristics or because of the very high costs of instituting eminent domain proceedings for the land required for towers in a straight line in highly developed real estate regions, that is to say, the towers are located wherever they are geographically or economically feasible even though they are not in a straight line. Stringing of wires on angle towers is, however, beset with considerable difliculty, Prior to tensioning the wires on angle towers it has been the practice to first attach to a yoke plate connected to the insulators suspended from the arm of the tower, a conventional wire-stringing block such as one of the A1100 series conductor blocks sold by the Campbell Specialty Company, Okmulgee, Okla. This wire string block consists of two sheaves mounted coaxial with, and on either side of a central drum. A single axle passes through all three and the two ends of the axle are journalled in two respective sockets located at the bottom ends of two outer vertical suspending members. The top ends of the latter members are pivotally mounted to apertures at each end of the yoke plate.

3,501,129 Patented Mar. 17, 1970 In using these blocks wires were first drawn over the two sheaves of the conventional block by means of a conventional wire running board. Then, prior to tensioning or sagging, the Wires were taken off the two sheaves and each was transferred to a different single pivoting sheave attached to the ends of the yoke plate. Such single sheaves could be, for example, the A1100 series multi-convertible single, independent sheaves also sold by the previously-mentioned Campbell Specialty Company. This transfer of the wires was considerably impeded by the fact that when this type of block is used on angle towers, the sideways thrust of the wires therein due to the angle of stringing caused the block to pivot about its pivoting mounting point. Thus, the block did not hang straight down but Was rather at an angle to the true vertical axis. Consequently, the wires in the conventional block were not parallel with respect to the horizontal and one of the two wires was higher than the other. This created an imbalance making the sagging in these spans complicated if not impossible to perform accurately and made the transfer of each wire from the regular block onto each of the single pivoting sagging sheaves a ditficult job requiring an undue number of man-hours and much use of expensive hoists, After the transfer was completed, tensioning was then applied to the wires to introduce the proper amount of sag, e.g. on the order of five tons. After the desired tension was attained, the single pivoting sheaves were removed and the wires were affixed to the permanent clamps.

It is among the objects of this invention to provide a novel method and apparatus for simplifying and reducing the cost of the procedure for installing conductors on high voltage wire towers, especially on angle towers. This novel method and apparatus thereby enables a much faster and much less expensive wire-stringing operation to be accomplished. Other objects which do not depart from the essence of this invention will occur to one skilled in the art upon perusal of the drawings, specification and claims herein.

BRIEF SUMMARY OF THE INVENTION In accordance with the present invention an assembly is provided which includes adaptor plates by which it is secured to a yoke plate that is attached to an arm of a power line tower. The assembly includes a central coathanger member which is pivotally suspended from the adaptor plates and is releasably connected at each end to a sheave subassembly. Each subassembly includes a horizontal tubular member having one end disposed in a vertical outer side mounting member. Each sheave is mounted for rotation about its tubular member. There is also a rotatable inner side member disposed toward the inner end of each tubular member, each inner side member initially hanging down from the tubular members. A removable inner shaft passes through the two coaxial sheaves and through the center of a drum disposed between them and is releasably secured at both ends to prevent axial movement thereof.

In operation, the two conductors are first pulled over and onto the tops of the two sheaves by a pull wire which rides in a groove in the central drum. The two inner side members are rotated to a vertical position and secured to the respective sheave subassemblies so that the two tubular members can independently support the sheaves. Then the central shaft is axially pulled out whereupon the drum is removed. Following this, whichever sheave subassembly is higher is lifted a predetermined distance and a rigid strap of a predetermined length is pinned between that subassembly and the adaptor plate. Then the other subassembly is similarly lifted a predetermined distance and a similar rigid strap is inserted in the same manner. Next, the coat-hanger is removed so that each subassernbly is now independently supported with a conductor riding over the sheave therein. Finally, the wires are tensioned by a winch whereupon they are transferred from the sheaves to their respective permanent retaining clamps.

BRIEF DESCRIPTION OF THE FIGURES FIGURE 1 is a front elevation view of the one embodiment of the present invention and FIGURE 2 is a side sectional view of the apparatus shown in FIG. 1 taken along the section line 22.

DETAILED DESCRIPTION OF THE FIGURES Referring to FIGS. 1 and 2, there is shown a wire stringing assembly constructed in accordance with the present invention just prior to the removal of the central drum. Insulators 5 and 6 are suspended from an arm of the angle tower and their lower ends are connected by ball devices 7 and 8 to apertures in a conventional yoke plate 10. In accordance with the present invention, an assembly which includes two adaptor plates 11 and 12 is first attached by

pins

15 and 16 on either side of the two lower ends of the yoke plate 10. Between these two adaptor plates and fixed thereto is a linkage member 17 whose upper end 17a is fixedly fastened to the adaptor plates by

pins

18 and 19. The linkage member 17 and two

lower tabs

17b and 170 welded to it at its lower end, the tabs having aligned apertures therein through which an easily removable pin 21 may be passed.

The central upper portion 20a of a member 20, known hereinafter as the coat hanger for descriptive purposes, is suspended, between the two tabs 17a and 17b by means of a pin 21 so that it is free to rotate clockwise or counterclockwise. The left and right extremities 20b and 200 of coat hanger 12 pass through two sets of

parallel mounting plates

13 and 14, each set consisting of two identical vertical plates, one on each side of the respective extremities of the coat hanger. Each set has four apertures, two of which are respectively aligned with a corresponding aperture in the left and right extremities.

Removable pins

22 and 24 may be passed through these aligned apertures. Each set also has two other, higher apertures through which pins 58 and 52 pass as will be explained later.

The lower edge of each set of mounting plates is affixed as by welding to the respective upper

horizontal members

25 and 26 of the left and right pulley subassemblies indicated generally at the

numerals

28 and 30. The pulley subassemblies 28 and have fixed outer

side mounting members

28a and 30a respectively whose upper ends are fastened by

bolts

29 and 30 respectively between apertured

downward portions

25a, 25b, and 26a, 26b fixed to the

horizontal members

25 and 26.

Members

28a and 30a support the ends of tubular pulley shafts 28b and 30b respectively which are fixed in apertures therein. The inner ends of the tubular members 28b and 30b pass through apertures in inner mounting plates 28c and 300 respectively. When the wire stringing operation begins, these inner plates are in the downward position as shown in phantom lines in FIG. 1. After the

wires

39 and 40 rest on the

sheaves

28d and 30d, the

plates

28c and 28d are revolved to the position shown in solid lines in FIG. 1 wherein their free ends are fastened by bolt and

nut devices

33 and 34 to the

members

25 and 26 respectively. The tubular shafts 28b and 30b are prevented from outer axial movement by

washers

35 and 37 and from inner axial movement by

nuts

36 and 38 which are screwed around threaded outer portions of the shafts 28b and 30b. Revolving about the shafts 28b and 30b are sheaves or

pulleys

28d and 30d respectively into which the

wires

39 and 40 are positioned as shown in FIG. 1 prior to tensioning them.

There is also a central drum 40 suspended rotatably about the midsection of an internal shaft 41 which passes through the hollow shafts 28b and 30b and is prevented from moving to the right by a pin 42 which passes through aperture 41a at the left end of the shaft 41. At the right end, a removing ring 41b is attached to enable 41 to be removed from the assembly at the appropriate time. Central drum 40 has a peripheral groove 40a around its midsection onto which a lead wire 45 is conducted. This lead wire 45 is used solely to draw the

conductors

39 and 40 over the

sheaves

28d and 30d as the running board is drawn through the assembly in the manner described later. If desired straps 48 and 50 may have one end thereof pinned by

pins

58 and 53 between the two sets of

plates

13 and 14 before the stringing process begins.

DESCRIPTION OF THE NOVEL PROCESS The first step in the wire stringing operation is to attach the assembly depending from the adaptor plates 11 and 12 to the yoke plate 10 with everything as shown in FIG. 1. At this time the inner side plates 28c and 300 are in their down positions shown in phantom lines. The two

wires

39 and 40 which are attached to the ends of the running board are first pulled through the assembly by the lead wire attached to the board. The running board may be approximately in the shape of a triangle with the two wires being connected toward the base angles thereof and the main stringing or lead wire being connected to an aperture in the apex thereof. It will be seen that the running board can be drawn just above the

sheaves

28d, 30d and the central drum 40 so that the lead wire 45 rests on the groove 40a and the two

conductors

39 and 40 rest on the

sheaves

28d and 30d. After the running board has been drawn through with the wires in the position shown the inner side plates 28c and 300 are revolved to the 12 oclock position and fastened by

bolts

33 and 34 to the

members

25 and 26.

The next step is to withdraw the pin 42 from the aperture 41a in the central shaft 41 and then by hand pull the central shaft 41 by ring 41b toward the right and out of the tubular shafts 28b and 30b. This will cause the central drum 40 to be free of the assembly.

The next step is to adjust the position of the coat hanger. Since the coat hanger 20 can pivot around pivot pin 21, and since the assembly is being used on an angle tower, the coat hanger 20 will not be exactly horizontal but will be pivoted somewhat, one of the ends 20b, 200 being higher than the other. Assuming that the right side of the coat hanger is somewhat higher than the left side, appropriate hoists are used to lift the right side 20c and the right set of vertical plates 13 a distance such that the strap 50 is then pinned by an easily removable pin 52 between the two adaptor plates whereas its lower end has already been pinned by a similar pin 53 between the set of two right parallel mounting plates 13. Now the strap 50 is bearing the load of the entire sheave subassernbly 30 so that the hoist or jack which has been under this right side during the afiixation of the strap 50 may be removed.

After the strap 50 has been affixed, a jack or a hoist is placed to the left member 25 so as to relieve the weight of the subassernbly on the right side so that the pin 24 may be easily removed to allow later removal of the coat hanger 20 itself.

The jack or hoist on the left side is then raised so as to enable the free aperture in the strap 48 to be pivoted until it becomes aligned with and between the apertures in the lower left corner of the adaptor plates 12 and 11. When they are so aligned a pin 56 is passed through all of the aligned apertures. A similar pin 58 has already been passed through the lower aperture in the strap which is aligned with corresponding apertures in the left set of vertical plates 14. Then the

pins

21 and 22 are removed.

The next step is to remove the coat hanger 20 and the supporting member 17. This is done by lowering the left and right ends 20b and 200 through the notches 28a of the member 28c and the notch 30c in the corresponding member 30c. The member 17 then may be removed by unpinning

pins

18 and 19. This leaves the eft and right pulley subassemblies 28 and 30 at nominally the same elevation but free to seek their own pivotal angle about

pins

56 and 58 on the left and pins 52 and 53 on the right.

The next step is to tension or sag the

wires

39 and 40.

After the desired tension has been attained, a hoist such as a coffin hoist lifts both subassemblies prior to their removal and the substitution of the permanent wire-retaining clamps.

I claim:

1. Apparatus for use in stringing and sagging a plurality of wires from a tower, comprising:

(a) a hanging member,

(b) first and second aligned sheave subassemblies releasably and pivotally secured to said hanging member, each of said subassemblies including:

(i) a sheave,

(ii) a horizontal tubular member on which said sheave rotates,

(iii) an outer and an inner vertical support member, said outer member being connected to support'the associated tubular member at all times, said inner member being rotatable to a first position in which it also supports said tubular member and to a second position in which the inner member does not support said tubular member and in which position one of a plurality of wires connected to a running board may be drawn over said sheave,

(c) roller means disposed between said inner support members, and

(d) an inner shaft which passes through said tubular members and said roller means and is axially removable therefrom.

2. The apparatus according to claim 1 with the addition of two rigid strap means respectively having one end releasably secured to one of said subassemblies.

3. The apparatus according to claim 1 with the addition of means pivotally and releasably connected to the central portion of said hanging member for suspending the latter, said suspending means also including means for releasably securing the other ends of said strap means thereto, said suspending means being adapted to be suspended from apparatus on said tower.

4. The apparatus according to claim 3 wherein each of said inner support members has a portion thereof formed to enable one end of said hanging member to pass through it when said hanging member is removed from said suspending means after the ends of said straps have been secured thereto and to said subassemblies and when said roller means has been removed from between said inner support members.

'5. The apparatus according to claim 1 wherein each of said subassemblies also includes an upper portion to which said outer and inner support members are connected, said upper portion including a pair of spaced vertical plates having first and second aligned sets of apertures formed therein and further wherein said hanging member has a 6 first and second apertures therein at the respective ends thereof, the first and second apertures being respectively aligned with sets of apertures and having removable pins passed through said aligned apertures.

6. The apparatus according to claim 3 wherein said suspending means includes two adaptor plates having sets of aligned apertures at each end thereof and a central member depending from a central point between said adaptor plates, said sets of aligned apertures being adapted to receive removable pins inserted to support the respective upper ends of said strap means.

7. The apparatus according to claim 5 wherein each of said inner vertical support members is fixed to said upper portion of its associated subassembly when in said first position after said inner shaft and said roller means have been removed.

8. A method for stringing wires on a wire tower in which at least two aligned sheave subassemblies mounted with a drum removably disposed between them is used, said method comprising the steps of:

(a) suspending said subassemblies and said drum pivotally from said tower at a point intermediate said subassemblies,

(b) drawing two spaced wires attached to a running board over the sheaves in said subassemblies by pulling said running board by a lead wire resting on said drum,

(c) supporting the sheave in each subassembly independently,

(d) removing said drum,

(e) adjusting the position of whichever one of said subassemblies is higher to a predetermined distance from said tower,

(f) releasably and pivotally securing said higher sub assembly to said tower at said predetermined distance,

(g) adjusting the height of the other subassembly until it is a predetermined distance from said tower,

(h) releasably and pivotally securing said other subassembly to said tower at said predetermined distance, and

(i) releasing the suspension of said subassemblies from said intermediate point whereupon each of said subassemblies independently is secured to said tower.

References Cited UNITED STATES PATENTS 3,077,337 2/1963 Cronkright 254--192 X 3,145,973 8/1964 MacFarlane 254-134.3 3,199,840 8/1965 Lindsey 254134.3 X

OTHELL M. SIMPSON, Primary Examiner DAVID R. MELTON, Assistant Examiner US. Cl. X.R. 254192