IEEE 2016

Since 2009, Shemar has devoted on research and application of composite cross-arm tower via our skilled R&D team and cooperation with State Grid and other influential grids globally. Shemar composite cross-arm tower has been verified feasibly as well as with superior flexibility and adaptability. Shemar composite cross-arm tower brings tremendous values to power grids. By now, it has passed all mechanical, electrical tests and full-scale tower test of AC 35kV, 110kV, 220kV, 330kV, 500kV, 750kV, and DC 800kV. Shemar composite cross-arm towers are fully qualified on transmission lines.

Comparing with conventional tower, Shemar composite cross-arm tower exceeds:

Narrow corridor and reduce tower footing;

Lower tower height and better accepted by residents;

Avoid rain/ice/pollution/snow flashover;

Avoid birds damaging and wind swing;

Enhanced protection against lightning;

Fast and easy transportation and installation;

Economic advantages with more reasonable comprehensive cost;

Cost-effective maintenance long maintenance-free period;

Application At a Glance of Shemar Composite Cross-arm Tower:

＊2015, AC 420kV British Hinkley Point output overhead line in UK;

＊2015, DC 800kV Lingzhou-Shaoxing transmission line in Ningxia Province;

＊2015, AC 220kV Xuchang-Changge transmission line in Henan Province;

＊2015, AC 220kV Yuntian-Huaichuan transmission line in Hunan Province;

＊2015, AC 110kV Urumchi urban transmission line in Sinkiang Province;

＊2013, AC 750kV South Hami-Shazhou transmission line in Sinkiang Province, the first application of composite cross-arm in UHV transmission project in the world; 3 years’ safe run;

＊2009, AC 220kV Maoqiang transmission line reform in Jiangsu Province; 6 years’ safe operation

Product details:

Based on successful application of composite insulated material in the field of substation, Shemar started to apply composite insulation material to overhead transmission line to make it more reliable and improve the economic efficiency. In 2008, through comprehensive discussion on technology research and development and verification, Shemar adopted combination of composite cross-arm and traditional steel tower body, and solved numerous problems with traditional steel tower, showing its tremendous technical and economic advantages.

Tower Structure

Adopt steel pipe pole in voltage classes among 35kV-110kV, adopt angle-steel tower in voltage classes above 220kV;

Adopt traditional steel tower body, which can effectively set lightning protection and grounding system compared with lattice tower, composite tower heads and full-composite tower;

Anti-aging and flame resistivity performs better than composite tower body;

Cross-arm design:

Adopt composite cross-arms instead of traditional steel arms and conductors are connected by hanging fittings instead of suspension insulators. The composite cross-arm material is FRP with silicone rubber shed injected on the surface. As for structure design on cross-arm, single-column, single-column with diagonal and double-column with diagonal are available according to the different voltage levels. When cross-arm is in horizontally layout, insulation extent is more than suspension insulators by 0.55m.

In conclusion: composite cross-arms' features on material and structure design manifest its tremendous technical and economic advantages.

 For voltage classes among AC 35kV-750kV and DC ± 800kV, structure type including single-column, single-column with diagonal and double-column with diagonal are available. At present, all designing schemes covering all voltage classes are completed with cooperation of design institute (Please see chart below).

Composite cross-arm tower has great advantages compared to traditional tower from design parameters such as tower height, corridor width, root distance, tower weight, which will save a lot of materials and costs. The comparison can be presented in the table below.