Blaw Knox T2175

Contents
Overview
T2175 is a 275 kV UK electricity pylon (steel lattice transmission tower) type. T2175 appears to have been designed by Blaw Knox around 1967 for the line between Dounreay and Beauly. Potentially it could have been used on an earlier line. Designation T2175 is taken from a set of Blaw Knox drawings captioned “North of Scotland Hydro Electric Board 275 kV Double Circuit Line Dounreay – Beauly”, contract DT/31, reference number T2175, drawn on various dates between 1967 and 1969. (L2 is T1011, L3 is T1120 and L3(c) is MT1120.)
T2175 is a derivative of L3 designed for heavier smooth-bodied 0.52□″ SCA instead of L3’s twin 0.175□″ SCA (0.52□″ is marginally under 50% more cross section area than twin 0.175□″). The line tower is the T1521 enhanced clearance tower rather than the original L3 version. The angle towers appear to be visually the same as L3 except that the crossarm bracing has been revised; insufficient data is presently available to be clear on precisely what was changed.
The Ground Engineering article Powering through dates Beauly–Dounreay to 1968; drawings for T2175 towers have been recovered dating to 1967.
The same towers are also used on the line between Foyers Substation and Knocknagael Substation, the latter being adjacent to Beauly–Blackhillock. This line uses twin conductor bundles of unknown conductor specification.
Can be confused with
- L3
- Blaw Knox T1521 (line tower)
General data
Contractor | Blaw Knox |
---|---|
Found | |
Height (straight line tower) | 125′–0″ (38.1 m) |
Voltage | 275 kV |
Dates back to | 1967–69 (drawings) |
Conductors |
Single Twin |
Design conductor | 0.52□″ smooth-bodied SCA |
Design earthwire | 0.175□″ SCA |
Tower forms
The following diagrams are shown to scale at 12 pixels per metre:
Examples
Both examples were taken just outside Wester Balblair (Baile a’ Bhlàir an Iar), across from Beauly substation.
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 | Weight |
---|---|---|---|---|---|
T2175 D STD | XM4451-5 | 125′–0″ (38.1 m) | 23′–0″ (7 m) | 43′–6″ (13.3 m) | |
T2175 D10 STD | XM4451-13 | 119′–3″ (36.3 m) | 25′–0″ (7.6 m) | 30′–0″ (9.1 m) | |
T2175 D30 STD | XM4451-18 | 119′–3″ (36.3 m) | 25′–0″ (7.6 m) | 35′–0″ (10.7 m) | |
T2175 D60 STD | XM4451-23 | 122′–9″ (37.4 m) | 33′–0″ (10.1 m) | 38′–0″ (11.6 m) | |
T2175 DT STD | XM4451-28 | 127′–0″ (38.7 m) | 37′–0″ (11.3 m) | 59′–6″ (18.1 m) | |
T2175 DTV45 STD | XM4451-38 | 127′–0″ (38.7 m) | 37′–0″ (11.3 m) | ? |
Source material
Drawings
Drawing no. | Tower | Drawing type | Series | Drawn | Amended | Originator | Other numbers |
---|---|---|---|---|---|---|---|
XM4451-5 | D (M42′–E60′) | Key Erection Diagram & Drawing Schedule | T2175 | July 1967 | — | Blaw Knox | BK35/22450 |
XM4451-6 A | D M42′ | General Arrangement & Erection Diagram | July 1967 | 28/02/1968 | BK35/22451 | ||
XM4451-7 | D (extensions) | August 1967 | — | BK35/22452 | |||
XM4451-13 A | D10° (M24′–E84′) | Key Erection Diagram & Drawing Schedule | 18/08/1967 | 29/10/1968 | BK35/22458 | ||
XM4451-18 | D30° (M24′–E84′) | 23/08/1967 | — | BK35/22463 | |||
XM4451-23 A | D60° (M24′–E60′) | January 1968 | 29/10/1968 | BK35/22468 | |||
XM4451-28 A | DT (M36′–E48′) | 14/11/1967 | 22/05/1969 | BK35/22473 | |||
XM4451-38 A | DTV45 | 29/04/1969 | 22/05/1969 | BK35/22482 |