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Blaw Knox T1648

Contents

Overview

T1648 is a 275/380 kV UK electricity pylon (steel lattice transmission tower) type designed for the North of Scotland Hydro Electric Board (NoSHEB), the operator of the non-CEB/CEGB portion of Scotland. Only a single drawing has been recovered, the GA&ED for the minimum height line tower. Lines with T1648 line towers use angle towers resembling L2 and it may be that contract T1648 was simply for an enhanced line tower. This would tally with the version of J L Eve L3 used in Scotland where only the line tower was redesigned. The enhanced line tower from Blaw Knox T2175 (itself a revised L3) was inserted into Blaw Knox L3 for the same reason: a line tower with greater clearances, used with the original angle towers.

Compared to L2 D, T1648 D has greater vertical phase clearances and extended middle crossarms. The tower body is also noticeably slimmer than L2 D, and slimmer even than L8 D.

T1648 only appears to have been used at 275 kV.

General data

Contractor Blaw Knox
Found Scotland
Height (straight line tower) 144′–3″ (44.0 m)
Voltage 275/380 kV
Dates back to 1961 (drawings)
Conductors Twin
Design conductor Twin 0.4″ SCA
Design earthwire ?

Lines

Lines so far known to use T1648 line towers:

Tower forms

The following diagram is shown to scale at 12 pixels per metre:

T1648 D

The verified (solid line) portion of the image is from Blaw Knox drawing XM3693/2F, tower type DM.20 (minimum height). The remaining steelwork (dotted line) is drawn per Google Street View imagery.

Examples

Tower details

Crossarm width is the total width across the widest crossarm pair, measured between the centres of the conductor attachment points rather than to the end of the steelwork.

Type Source Height Base width Crossarm width
T1648 D STD XM3693/2F 144′–0″ (44.0 m) Unspecified 52′–0″ (15.8 m)