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P.O. ENGINEERING DEPT
Issue 5, 3.11.37
Issue 6, 28.9.59
Issue 7, 1.1.70
Various pole-fittings such as roofs, finials, saddles and steps, are described
in the following paragraphs ; where necessary, instructions are given for
fixing. For "Numbering of Poles" see C 3161.
Roofs for poles are made of galvanized iron and are provided so as to prevent
the entry of moisture through the exposed pores at the tip of the pole. They
should be fitted to all poles except:-
- those carrying a finial,
- those used for Light Aerial Lines " (see H 3001),
- precut poles, except where, for uniformity or to meet the wishes of
Wayleave Grantors, the Sec. Engr. decides that roofs are necessary.
Two types are available in each size - "cut" for poles where saddles are
required, and "uncut" for poles without saddles. The former type is drilled with
a 3/16in. hole in the centre of the ridge and two 17/6in. holes in each side;
the latter has two holes in each side. Both types in each size are
The width of the roof should be slightly greater than the diameter of the tip of
the pole. To provide for this, four sizes of each type of roof are available as
shown in Table 1.
5. Fitting the roofs
Cutting the top of the pole. If necessary, the tip of the pole should be sawn
square. Two cuts sloping at about 45 deg. to the axis of the pole should then be
made, as shown in Fig. 1, so that the roof will fit the pole closely. After
cutting, the top of the pole should not form a sharp central ridge but should
present a flat surface, about 1¼ inches
wide. The cuts should be made so that the roof will fit the pole closely and so
that the ridge of the roof will be parallel with the arms, i.e. at right-angles
to the direction of the line-wires.
6. If a Saddle is required, a 5/8in. hole should be bored in the centre of
the tip of the pole, to a depth sufficient to accommodate that portion of
spindle which will protrude from the underside of the saddle.
7. "Creosote and tar" must be thoroughly applied to the exposed end-grain at
the pole top before the roof is fixed.
FIG. 1. - CUTTING THE TOP OF THE POLE TO FIT THE ROOF
Roofs used with Saddles are secured to the pole by means of the fastenings for
the saddles, i.e. four "Screws, Coach" The coach-screws, which are of the
fetter-drive type, are designed to be driven in with a hammer, all but the last
half-inch, which must be screwed home.
Roofs used without Saddles should be fixed by means of four "Nails, Rosehead, 2
TYPES AND SIZES OF ROOF
||Class of pole on which
(for use with saddles)
(for use without saddles)
||Roof No. 1
||Roof No. 2
||Roof No. 3
||Roof No. 4
||Roof No. 5
||Roof No. 6
||Roof No. 7
||Roof No. 8
10. "Saddles, Galvanized"
These are used when it is necessary to erect one or two additional wires in
cases where, by so doing, the carrying capacity of the pole will not be
exceeded, but where clearance is not available to allow an additional arm to be
added without substituting longer poles. As the insulation of the saddle is
always lower than that of other wires, this position should not as a rule be
used for long circuits. The saddles have a central hole to take either a fin.
straight spindle (for a single wire) or a "Bolt, No. 6" (used with a "Spindle,
No. 13, 14, or 15") for two wires : a square recess at the bottom of the hole
accommodates the nut of the spindle or bolt.
11. Assembly of Saddles and Spindle
The saddle and its spindle should be assembled before the saddle is fixed in
position. The washer should be fitted between the top of the saddle and the
shoulder of the spindle or head of the "Bolt, No. 6" (if used).
Saddles should be fixed centrally with the pole, as indicated in para. 8.
13. "Stays, Saddle"
These should be used for saddles on:-
- all A-poles (see C 3251)
- for all other poles at angles
- at all points where saddle-wires are terminated, and
- on all LIGHT (and EXTRA LIGHT) poles.
14. Saddle stays are made of galvanized hoop-iron and are available in three
sizes, Nos. 1, 2, and 3, for use with "Roofs, Nos. 1, 3, and 5" on average
LIGHT, MEDIUM and STOUT poles, respectively. If a saddle is to be fitted where a
"Roof, No. 7" is required (e.g. on a STOUT A-pole), a "Stay, Saddle, No. 3"
altered locally, should be used.
FIG 2 - SADDLE STAYS
15. Fixing of the stay to the saddle is accomplished by means of the spindle
of "Bolt, No. 6" and the assembled stay and saddle is secured to the pole-tip by
means of coach-screws (see para. 8). "Wedges, Hardwood" should be inserted
between the pole and the saddle-stay as shown in Fig. 2. These are available in
four thicknesses, ½in.,
¾in., 1in. and 1¼in.,
known as "Nos. 1, 2, 3, and 4" respectively, and should be trimmed, if
necessary, so as to fill the triangular space between the pole, the roof and the
saddle-stay. The wedges should be fixed to the pole by "Nails, Wire, 2 in."
independently of the fixings of the stay.
The use of finials on wooden poles should be restricted to cases where
ornamental poles are insisted upon, by wayleave grantors, for poles in places
where amenities receive some consideration, and to poles fitted with pole-heads
for open-wire or drop-wire distribution. The standard type of finial is
illustrated in Fig. 3.
FIG 3. - FINIAL
Three sizes are available as shown in Table 2.
DETAILS OF FINIALS
||Diameter of dowel
||Class of pole for which
||Finials No. 1
||Finials No. 2
||Finials No. 3
18. "Collars, Pole Top"
If a pole is of such a diameter that the base of the finial is not large enough
to form a suitable cap, a "Collar, Pole Top" should be interposed between the
finial and the pole-top. This is a wooden disk l½in.
thick, diameter 8½ to 12 inches to suit the
size of pole, with radiused edges and a clearance hole drilled in the middle to
admit the dowel-screw of the finial. The top of the pole must not be pared down
to the diameter of the base of the finial.
19. Fixing the finial
The finial is fixed to the pole by means of the screwed dowel. To facilitate
fixing, the tip of the pole should first be sawn square and a hole, of the same
diameter as that of the dowel, drilled in its exact centre to a depth of 3in.
Then using a bit of 1/8in. less in diameter, the hole should be continued to a
total depth of 6 inches. Finally "Creosote and Tar" should be liberally applied
to the cut surfaces, and the finial may then be screwed down by hand.
20. "Steps, Pole"
Steps Pole No. 1 are used for Wooden poles and should be fitted alternately on
opposite sides of the pole, at right-angles to the line of wires, i.e. parallel
with the arms, and 15in. apart (The distance between any two steps on the same
side of the pole will then be 2ft. 6in.). Each step should be fixed by means of
three coach-screws (see para. 8). Steps, Pole No. 2 are used on Steel poles (see
steel poles section for more information).
Issue 6 additional
Three patterns of Steps, Pole, No. 1 are issued: the standard P.O. type, the
pressed steel. type (both of which have three fixing holes in line) and the
Barton type, which has one fixing hole on each side level with the tread and one
at the lower end of the strut Issue 7 advises that only the Barton step is now
Issue 6 additional
Steps, Pole No. 1 are secured to the pole by means of Screws, Coach, which are
designed to be driven in with a hammer, all but the last A in, which must be
screwed home. The screws should be driven into the pole in a horizontal
direction, so that the head of the screw beds firmly on the pole step. The coach
screws should only be fitted to sound timber. They should not be driven into
shakes or old screw-holes.
21. The highest step should be about 15in. below the bottom arm; on poles
carrying only a saddle-wire, the highest step should be about 3ft. 9in. below
the wire, and in line with the wire. When new arms are added, the topmost step(s)
should be shifted as required.
22. Two additional steps should be fitted at a point 2ft. 6in. below the
level of the bottom arm (see Fig. 4). On poles carrying only a saddle-wire, an
additional step should be fitted opposite to the highest step.
FIG 4 - SHOWING THE NORMAL SPACING OF STEPS
23. The lowest step should be approximately 15ft. above ground level. On
D.P.s on property not accessible to the public, the steps may be continued lower
NOTE - In the past it was not the practice to provide steps to within 15ft.
of the ground, with the result that the bottom step cannot be reached readily
from the "Ladder, Extension No. 4", which is now in general use. Existing D.P.s
where such a condition exists, and on which frequent work is likely to be
necessary, should therefore be fitted with additional steps to within 15ft. of
the ground. This should be done, not as a separate and special work, but in
conjunction with other work on the D.P. concerned, as opportunity permits.
Issue 7 additional
STEPPING OF POLES WITH ARMS
Issue 7 additional
STEPPING OF AERIAL CABLE AND DROPWIRE POLES
24. On A-poles, steps should be fitted as in paras. 21-23. Up to the double
step 3ft. 9in. below the lowest arm (see Fig. 5), the steps should be fitted
parallel to the line of the wires: above that point, steps should be at
right-angles to the line of the wires, and may be on one or both limbs of the
pole, as found most convenient.
25. On poles fitted with a ring-type pole-head, four steps
should be fitted at right-angles to one another, at a point 4ft. below the level
of the topmost ring. These steps should be set at an angle of 45 degrees to the
line of the normal steps (see Fig. 6). Below this point the pole should be
fitted with steps in the usual way.
Issue 6 additional
The Barton type step is not suitable for use at the four-step level of a
ring-type D.P. as the fixing lugs each side of the tread may overlap and/or
prevent the fitting of the Capping, Steel, No. 3 used for protecting the cable
at this point.
Issue 6 additional
Stirrups, Pole Step
To enable two men to obtain a secure foothold at the same step position
Stirrups, Pole Step, may be attached to the pole step temporarily at the desired
position. The stirrup is designed to fit on to Steps Pole, No. 1 (either P.O. or
Barton pattern) but not Steps, Pole No. 2. Before attachment of the stirrup it
should be ensured that the step and coach screws are capable of bearing the
STIRRUPS, POLE STEP
FIG. 5. - SHOWING THE SPACING OF STEPS ON AN A-POLE
FIG 6. - PLAN SHOWING THE ORIENTATION OF THE STEPS ON A
POLE WITH A RING TYPE HEAD
26. For use with iron poles, a special type of step, known as "Clips,
Climbing" should be provided.
27. Poles to which street-lighting fittings, road indicator or other signs
are attached, should be fitted with steps above the point of attachment of the
sign or fitting, to obviate the necessity of using climbers above the sign.
28. Reflectors on Poles. Fixing of Reflectors by A.A. or R. A . C.
The fitting and maintenance of reflex disks authorized under WAYLEAVES,
Attachments, A 0511, will be performed by these Bodies.
29. Fixing of Reflectors by the Department.
"Reflectors, Disk" may be fitted at the discretion of the Sec. Engr. on selected
poles and on poles in respect of which complaints have been made by Road
Authorities or members of the public, where such complaints are considered to be
30. Following the issue of a report on traffic signs by the Ministry of
Transport in 1933, the earlier (strip) reflector was made obsolescent and the
present reflector introduced.
31. The new reflector is a light metal disk, 6 inches in diameter, with a
curved back to facilitate attachment to a pole. Fourteen red, reflex lenses are
inserted in the face of the reflector.
32. Fixing Reflectors
To obtain the best effect, reflectors should be fixed in such a position as will
ensure correct alignment with oncoming traffic. In the past there has been a
tendency to fix reflectors at too great a height above the ground line; the
ideal height is 3ft. 6in., measured from the crown of the road to the lower edge
of the reflector. Where reflectors fitted at this height are liable to be
obscured, it will, of course, be necessary to exceed this height, but it should
be exceeded by as little as possible, and in no instance should the height be
more than 6ft. 9in.
Earthing and Step provision
Roofs, Finials and Rings type distribution