BOOK_CONTENT
From Lineman's and Cableman's Handbook, Eleventh Edition

Sagging operations begin as soon as the conductor stringing is completed, to establish the proper conductor tension for the conditions at the time the work is performed. The correct conductor tension and sag for various sag or control spans are detailed in the construction specifications or standards to provide proper clearances. The weather conditions, including temperature and wind velocity, must be taken into consideration to complete the process. The proper conductor tension can be obtained by establishing the proper sag in the control spans. Sighting methods using a surveyor's transit or targets can be used to measure the sag in the conductor. The tension in the conductor can be measured with a dynamometer or determined by timing mechanical waves induced into the conductor.

All conductor grips, come-alongs, stringing blocks, and pulley wheels used in the sagging operations must be of a design which will not damage the conductors by kinking, scouring, or unduly bending them. Sag sections must be selected before the operations are started. The lengths of sag sections are limited by dead-ends, angle structures, and the terrain. The sag sections are normally not longer than 4 miles.

Sag sections must have control spans. The control spans will be used to measure the sag for each sag section. If the control spans are properly sagged, the conductors in the sag section should all be at the proper tension. The control spans should be approximately the length of the ruling span. Ruling spans are a calculated dead-end span length assumed...

Copyright The McGraw-Hill Companies, Inc. 2007 under license agreement with Books24x7

Products & Services
Traction and Tension Dynamometers
Traction dynamometers and tension dynamometers are used to measure force in tension, traction and weighing applications with cables, guy wires and chain.
Beams, Joists, and Wall Studs
Rafters, beams, and joists are structural profiles that are used to frame buildings.
Accordion Bellows and Protective Boots
Accordion bellows and protective boots are convoluted, expandable, fabric or elastomer components used to protect screws, shafts, slide ways and other components from liquid, chips, dirt and other debris.
Crimp Tools

Crimp tools are designed for the connection of electrical and metal components by cutting, stripping, bending, and deforming. Crimping is extensive in the electrical and metal-forming industriesand it was developed as a high-quality, low cost replacement for soldered terminations. This article does not reference hose crimping processes.

Spherometers
Spherometers are used to measure the radius or curvature of spherical surfaces such as optical lenses, spherical mirrors, and balls.

Topics of Interest

Transmission- and distribution-line conductors must be joined together with full-tension splices if the conductors are under tension. Bolted connectors can be used to join electric conductors at...

Appendix 5.1: : Conductor Sag and Tension Calculations Referring to the diagram in Section 5.3 the true length of the conductor from C to B may be calculated from: Hence the complete conductor...

7.1 Scope The next two chapters look at conductors the workhorse of the overhead line. Chapter 8 looks at the electrical choice for conductors and how to calculate what is required. This chapter,...

A urethane timing belt moves samples into position in this CAD simulation of an automated blood sampling machine. Timing-belt drives transmit torque and motion from a driving to a driven pulley or...

Chapter C: C Cylinder Formulas C carbon (element) Ca calcium (element) cable length = 120 fathoms 0.1185 mi (naut) 720 ft 0.1364 mi (stat) 219.456 m cable sag CATENARY FORMULAS caliber unit...