Composite station post insulators

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Overview

The composite station post insulators are widely applied to disconnector,devices in electric transformer substations, convertor stations and tubular bus-bar and other primary equipment. With so many special advantages, composite station post insulator is increasing its market shares. According to company standard Q/GDW-383 SMART CONVERTOR TECHNOLOGY GUIDE, which is stated by State Grid Corporation of China, “primary equipment should be with high reliability, apply composition material as outer insulation, and suitable for the working environment. 

According to customers requirements, post insulator can be made for voltage of  33kV,  69kV, 132kV, 230KV, 300kV, 400kV, 500kV ... 

Mostly, the plymer post insulators are used to support bus-bars in transformer sub-station yards, support breakers in switchgear, and support capacitor banks etc. These plymer post insulators are generally subjected to bending, torsion and compression forces in service. They may also be installed horizontally, vertically, or underhung some times, and different installations will be accoring to different applications. They can be designs according to IEC, ANSI and other standards or to customer specification, in the factory of GW.

When do we need to replace the porcelain post insulators by composite plymeric station post insulators?

The mechanical heights are the same and electrical performance is comparable to the porcelain ANSI TR Numbers. This means in most cases they are direct replacements, one to one.

For many years substations were constructed using porcelain post insulators. After working so many years, many porcelain post insulators need to be replaced. But the height of many porcelain post insulators used before are different from what we are using today. That make it hard to use new ones to replace the old ones directly.

However, Xiangyang Guowang's composite station post insulators offer a better choice, that is to say we can offer composite station post insulators with appropriate height that can directly replace the old porcelain ones without adjust the bus or switches.

Besides, the composite station post insulators are usually cheaper than the porcelain station insulator. 

Also composite station post insulators can be made to one piece, instead of installed together by several shorter ones.

Structure and process of the composite post insulators

Housing (sheath and sheds)

Sheath and sheds of composite long rod polymer Insulators are made of HTV silicone-rubber (VMQ - Vinyl-Methyl-Polysiloxane, with filler additives) free of EPDM or other natural origin rubbers.Silicone-rubber is HTV solid silicone type (High Temperature Vulcanized – solid silicone rubber).This type of silicone rubber is solid and vulcanizes at a high temperature (near 200ºC).

Core

The ECR fiberglass rod, which produced from epoxy resin and glass fiber, has ability of high electrical integrity & high resistance to acid corrosion. Epoxy resin resistant to hydrolisys reinforced with glass fiber resistant to corrosion in order to transmit the mechanical stresses produced by conductors to the support and provides the necessary electrical insulation.The core is the component to bear mechanical load and has minimum tension strength at 1000Mpa.

Molding Process

compare with compression molding way, injection type insulators molding will make the thickness of insulator's housing more balance, which can get a much higher quality products. Also the injection machine is equipted with cold runner system, which will make the rubber the keep in melting status, during flowing inside the mold.

Functions

Composite Station post insulators have the advantages of anti-pollution flashover, high strength, light weight, anti-impact, easy for maintenance and project costs saving etc. The composite post insulators are widely applied to:

• Post-type circuit breaker
• Disconnector
• Electric reactor
• Converter valve

Advantages

• Excellent performance of hydrophobicity, anti-aging, anti-tracking, anti-erosion.
• High tension & bending strength, high mechanical strength, anti-impact, shake-proof and not fail easily for brittle.
• Light weight & small, convenient for installation, the dimensions can be customized, and interchangeable with porcelain post insulators.
• Don’t need to be manually cleaned, which make it safer.
• Application: post-type circuit-breaker, disconnector, current limiting reactor, paralleling resistor, converter valve and many other outer insulation posts of equipment.

Reference Project

Composite post insulators are applied to Hunan-Hubei soft current exchanging tower of direct current power transmission system. It works normally and don’t need to be clean which save a lot labor cost.	In the current exchange station of ±800KV ultra high voltage direct current power transmission substation. One piece pole post insulators are used to replace porcelain post insulators which need more than 3 pieces mounted together.	Composite post insulators can be applied for disconnectors, switchgears in substation with voltage of 11kV – 500kV. The post can be made in one piece. Or it can be installed together with several pieces

Parameters （IEC 60273）

Technical Refemrence Number	Model	BIL Rating kV	Power Frequency Withstand Wet	Height mm	Leakage Distance mm	Bolt Circle mm		Cantilever Strength kN	Torsional Strength N·M
						top	base
C2-325	GW-325-CT6	325	140	770	2150	127	127	6	2000
C4-325
C6-325	GW-325-CT8				1950	127	127	8	3000
C8-325
C10-325	GW-325-CT12.5				1800	127	127	12.5	4000
C12.5-325
C16-325	GW-325-CT16				2000	127	225	16	5000
C20-325	GW-325-CT20				2000	127	254	20	6000
C2-450	GW-450-CT5	450	185	1020	3000	127	127	5	1800
C4-450	GW-450-CT8				2800	127	127/178	8	2500
C6-450	GW-450-CT10-1				2700	127	127/178	10	3500
C8-450	GW-450-CT10-2				2700	127	127/200	10	4000
C10-450	GW-450-CT10-3				2700	127	127/225	10	4000
C12.5-450	GW-450-CT12.5				2950	127	225	12.5	6000
C16-450	GW-450-CT16				2950	127	254	16	6000
C20-450	GW-450-CT20				2950	127	254	20	6000
C2-550	GW-550-CT6-1	550	230	1220	3600	127	127	6	2000
C4-550	GW-550-CT6-2				3600	127	127/178	6	3000
C6-550	GW-550-CT8-1				3350	127	127/200	8	4000
C8-550	GW-550-CT8-2				3350	127	127/200	8	4000
C10-550	GW-550-CT10				3350	127	127/225	10	4000
C12.5-550	GW-550-CT12.5				3750	127	254	12.5	6000
C16-550	GW-550-CT16				3750	127	254	16	6000
C20-550	GW-550-CT20				3750	127	275	20	6000
C2-650	GW-650-CT6-1	650	275	1500	4600	127	127/178	6	2000
C4-650	GW-650-CT6-2				4600	127	127/200	6	3000
C6-650	GW-650-CT6-3				4600	127	127/200	6	3000
C8-650	GW-650-CT8				4800	127/225	127/225	8	4000
C10-650	GW-650-CT10				4800	127/225	254	10	4000
C12.5-650	GW-650-CT12.5				4800	127/225	254	12.5	6000
C16-650	GW-650-CT16				4650	225	275	16	6000
C20-650	GW-650-CT20				4700	225	300	20	6000
C2-750	GW-750-CT4-1	750	325	1700	5100	127	127/178	4	2000
C4-750	GW-750-CT4-2				5100	127	127/200	4	3000
C6-750	GW-750-CT6				4800	127/225	127/225	6	3000
C8-750	GW-750-CT8				5300	127/225	127/225	8	4000
C10-750	GW-750-CT10				5300	127/225	254	10	4000
C12.5-750	GW-750-CT12.5				5200	127/225	254	12.5	6000
C16-750	GW-750-CT16				5200	225/254	275	16	6000
C20-750	GW-750-CT20				5200	225/254	300	20	6000
C4-850	GW-850-CT4	850	360	1900	5800	127	200	4	3000
C6-850	GW-850-CT6				5500	127/225	225	6	3000
C8-850	GW-850-CT8				6000	127/225	254	8	4000
C10-850	GW-850-CT10				6000	127/225	254	10	4000
C12.5-850	GW-850-CT12.5				6000	127/225/254	254	12.5	6000
C16-850	GW-850-CT16				6000	225/254	275	16	6000
C20-850	GW-850-CT20				6000	225/254	300	20	6000
C4-950	GW-950-CT4	950	395	2100	6200	127	200	4	3000
C6-950	GW-950-CT6				6900	127/225	225	6	3000
C8-950	GW-950-CT8				6900	127/225	254	8	4000
C10-950	GW-950-CT10				6900	127/225	254	10	4000
C12.5-950	GW-950-CT12.5				6900	127/225/254	275	12.5	6000
C16-950	GW-950-CT16				6700	225/254	300	16	6000
C20-950	GW-950-CT20				6700	225/254	325	20	6000
C4-1050	GW-1050-CT4	1050	460	2300	6900	127	200	4	3000
C6-1050	GW-1050-CT6				7700	127/225	225	6	3000
C8-1050	GW-1050-CT8				7700	127/225	254	8	4000
C10-1050	GW-1050-CT10				7700	127/225	275	10	4000
C12.5-1050	GW-1050-CT12.5				7700	127/225/254	275	12.5	6000
C16-1050	GW-1050-CT16				7600	225/254	300	16	6000
C20-1050	GW-1050-CT20				7600	225/254	325	20	6000
C4-1175	GW-1175-CT4	1175		2650	8050	127/225	225	4	3000
C6-1175	GW-1175-CT6				9000	127/225	254	6	3000
C8-1175	GW-1175-CT8				9000	127/225	254	8	4000
C10-1175	GW-1175-CT10				9000	127/225	275	10	4000
C12.5-1175	GW-1175-CT12.5				8900	127/225/254	300	12.5	6000
C16-1175	GW-1175-CT16				8900	225/254	325	16	6000
C20-1175	GW-1175-CT20				8900	225/254	356	20	6000
C4-1300	GW-1300-CT4	1300		2900	10000	127/225	225	4	3000
C6-1300	GW-1300-CT6				10000	127/225	254	6	3000
C8-1300	GW-1300-CT8				10000	127/225	275	8	4000
C10-1300	GW-1300-CT10				10000	127/254	275	10	4000
C12.5-1300	GW-1300-CT12.5				9850	127/225/254	300	12.5	6000
C16-1300	GW-1300-CT16				9750	225/254	325	16	6000
C20-1300	GW-1300-CT20				9750	225/254	356	20	6000
C4-1425	GW-1425-CT4	1425		3150	11000	127/225	225	4	3000
C6-1425	GW-1425-CT6				11000	127/225	254	6	3000
C8-1425	GW-1425-CT8				11000	127/225	275	8	4000
C10-1425	GW-1425-CT10				11000	127/225	300	10	4000
C12.5-1425	GW-1425-CT12.5				10850	127/225/254	325	12.5	6000
C16-1425	GW-1425-CT16				10750	225/254	356	16	6000
C20-1425	GW-1425-CT20				10600	225/254	356	20	6000
C4-1550	GW-1550-CT4	1550		3350	11700	127/225	225	4	3000
C6-1550	GW-1550-CT6				11700	127/225	254	6	3000
C8-1550	GW-1550-CT8				11700	127/225	275	8	4000
C10-1550	GW-1550-CT10				11600	127/225	300	10	4000
C12.5-1550	GW-1550-CT12.5				11600	127/225/254	325	12.5	6000
C16-1550	GW-1550-CT16				11600	225/254	356	16	6000
C20-1550	GW-1550-CT20				11400	225/254	356	20	6000
C4-1675	GW-1675-CT4	1675		3650	13000	127/225	254	4	3000
C6-1675	GW-1675-CT6				13000	127/225	275	6	3000
C8-1675	GW-1675-CT8				13000	127/225	300	8	4000
C10-1675	GW-1675-CT10				12800	127/225	300	10	4000
C12.5-1675	GW-1675-CT12.5				12800	225/254	325	12.5	6000
C16-1675	GW-1675-CT16				12650	225/254	356	16	6000
C4-1800	GW-1800-CT4	1800		4000	14200	225/254	254	4	3000
C6-1800	GW-1800-CT6				14200	225/254	275	6	3000
C8-1800	GW-1800-CT8				14200	225/254	300	8	4000
C10-1800	GW-1800-CT10				14200	225/254	325	10	4000
C12.5-1800	GW-1800-CT12.5				14000	225/254	356	12.5	6000
C16-1800	GW-1800-CT16				13850	225/254	356	16	6000
C4-1950	GW-1950-CT4	1950		4400	15650	225/254	254	4	3000
C6-1950	GW-1950-CT6				15650	225/254	275	6	3000
C8-1950	GW-1950-CT8				15450	225/254	300	8	4000
C10-1950	GW-1950-CT10				15350	225/254	325	10	4000
C12.5-1950	GW-1950-CT12.5				15350	225/254	356	12.5	6000
C4-2100	GW-2100-CT4	2100		4700	16400	225/254	254	4	3000
C6-2100	GW-2100-CT6				16400	225/254	275	6	3000
C8-2100	GW-2100-CT8				16400	225/254	300	8	4000
C10-2100	GW-2100-CT10				16400	225/254	325	10	4000
C12.5-2100	GW-2100-CT12.5				16400	225/254	356	12.5	6000
C4-2250	GW-2250-CT4	2250		5000	17800	225/254	254	4	3000
C6-2250	GW-2250-CT6				17800	225/254	300	6	3000
C8-2250	GW-2250-CT8				17800	225/254	325	8	4000
C10-2250	GW-2250-CT10				17800	225/254	356	10	4000
C12.5-2250	GW-2250-CT12.5				17800	225/254	356	12.5	6000
C4-2400	GW-2400-CT4	2400		5300	19100	225/254	254	4	3000
C6-2400	GW-2400-CT6				19100	225/254	300	6	3000
C8-2400	GW-2400-CT8				19100	225/254	325	8	4000
C10-2400	GW-2400-CT10				18900	225/254	356	10	4000
C12.5-2400	GW-2400-CT12.5				18900	225/254	356	12.5	6000
C4-2550	GW-2550-CT4	2550		5700	20500	225/254	275	4	3000
C6-2550	GW-2550-CT6				20500	225/254	300	6	3000
C8-2550	GW-2550-CT8				20500	225/254	325	8	4000
C10-2550	GW-2550-CT10				20500	225/254	356	10	4000

FAQ

What is BIL for post insulator?

Insulation levels are designed to , rather than only normal operating voltages. Since the insulation lines and equipment is protected by surge arresters draining the surges rapidly before the insulation is damaged, the arrester must operate below the minimum insulation level that must withstand the surges.

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