Milliken K721

Contents

• Overview
  • General data
• Can be confused with
• Lines
• Tower forms
  • Examples
• Tower details

Overview

Milliken K721 is a 66 kV distribution tower type designed around 1934 and found in the north-east of England.

Uncharacteristically, the line tower is designated “D” rather than (per 33 and 66 kV convention) “D3”.

Northern Powergrid document [NSP/004/030] gives it as a “Knursling” type, but thus far there is no evidence to support the idea that K721 was designed for a line terminating at Nursling. The other “Knursling” type indicated by Northern Powergrid is Blaw Knox K9906, which is indeed an SWE type used for the line between Nursling and Lepe (likely to be SWE SL11).

General data

Designed for	?
Design contract	Milliken Brothers K721
Found
Height (straight line tower)	62′–1″ (18.9 m)
Voltage	66 kV
Dates back to	1934
Circuit count	Double
Known conductors	Single
Design conductor	0.15□″ SCA
Design earthwire	?
Normal span	700 feet (0.15□″ SCA standard conductor) 630 feet (0.2□″ SCA alternative conductor)
Drawing ranges	K721 / XM1077

Can be confused with

• Milliken E102 (unconfirmed double-circuit towers)
• Milliken E177 (D3)

Lines

Lines using Milliken K721 towers include:

• Blyth substation to Reservoir substation (Bedlington); the line terminates on an SEE SL8-style gantry.
• A short line out of Blyth substation terminating beyond Bebside on an L4(m) 66 tower.
• The latter half of the line from Coalburns substation to Hexham (the first half is PL16 and L4(m)).

Tower forms

The following diagrams are shown to scale at 12 pixels per metre:

D20 and D60 remain preliminary only due to incomplete dimensions, pending more accurate material; these are based on Google Street View, scaled to the known vertical dimensions.

Examples

Out of range.

Tower details

See dimensions on the site guide page for a key to the tables.