Rashtra Udhyog Limited

Anchor Shackle, U-Clevis are supplied in galvanized forged steel as per various strength requirements. Suitable bolt with nut or rivet are supplied fitted with the fitting.

 

Various sizes, mechanical ratings are available to suit insulator units.

Single point and double point horns in galvanized mild steel flat type upto 69 kV, round ball ended type upto 138 kV and Pipe Type upto 230 kV.

 

For voltage of 380 kV or above corona rings are supplied normally made of aluminiun alloy.

 

The values for radio interference voltage , corona protections are always kept below the normal internationally specified limits.

Single point and double point arcing horns in galvanized mild steel flat type upto 69 kV, round ball ended type upto 138 kV and Pipe Type upto 230 kV are available.

 

For voltage of 380 kV or above corona rings are supplied normally made of aluminiun alloy.

 

The values for radio interference voltage , corona protections are always kept below the normal internationally specified limits.

 

Power Transmission Lines should be provided with maximum possible service safety to avoid possible damages to insulators and conductors.

 

Flashover is often the cause of outages due to high arc temperature which may damage the conductors and destroy the insulators. Arcing protections an important feature of equipment design. They consists of horns, Grading rings, the shapes and sizes of which are in accordance with system voltage and standardised by High Voltage Electrical Tests. Aluminium Corona Control Rings are supplied for High Voltage applications above 330 KV. A properly designed protection device will avoid the flashover damaging the insulator string. It will make the arc start away from the line conductor and ensure that during all the flashover time the arc is kept away from the insulator string. The ring shape design give a more linear voltage distribution all along insulator string, thus avoiding bottom insulator from Electrical over stress. While for system voltage upto 220KV conventional flat type, ball and rod type and tubular racquet type arcing horns are adequate for UHV lines i.e. 400KV and above special designs are developed.

 

RUL has conducted extensive test on various design to optimist its performance under fault conditions. The range is wide both from configuration and size and this catalogue illustrates the basic form of some of the commonly used designs. The arcing/grading rings are produced both in steel (HDG) and satin finish aluminium alloy tube (UHV application).

Available in high strength, high conductivity aluminum alloy for both tapered and performed type.

 

Ferruels, dies and presses for tapered rods available on request.

 

Performed rods are ball ended type for corona free performance and can be applied without tools.

Ball hooks, Ball Links, Eye hooks are supplied in galvanized forged steel as per British Standard specification standards ball sizes11 mm, 16 mm, 20 mm ,24 mm.

Ball Clevis & Ball eye available in both galvanized forged steel & malleable/S.G cast iron.

 

Ball hook & Ball Link are available both normal & horn holder type.

 

Ball designations to suit other International specifications ANSI, DIN, IEC and ISO standards are available.

 

Various Mechanical ratings are available to suit insulator units. Other international standard fittings on request.

Ball hooks, Ball Links, Eye hooks are supplied in galvanized forged steel as per British Standard specification standards ball sizes11 mm, 16 mm, 20 mm ,24 mm.

 

Ball Clevis & Ball eye available in both galvanized forged steel & malleable/S.G cast iron.

 

Ball hook & Ball Link are available both normal & horn holder type.

 

Ball designations to suit other International specifications ANSI, DIN, IEC and ISO standards are available.

 

Various Mechanical ratings are available to suit insulator units. Other international standard fittings on request.

Supplied In galvanized forged steel for all requirements and to match link fittings.

 

Various sizes , mechanical ratings are available to suit insulator units.

We can offer compression dead end fittings complete with nuts bolts & jumpers, for all sizes of conductors & earthwires. Dead End Clamps are made of Extruded Aluminium Alloy.

 

Forged steel dead ends options are available for Link, Eye & Clevis attachments.

 

Compression type dead ending is most widely accepted practice on EHV lines because of its high Mechanical reliability and Electrical continuity. For distribution line bolted type clamps are popular mainly because of easier installation, without any special tool, maintenance advantage and continuity of jumper. However because of vibration and loosening problems quite often localized heating affects performance and cause outage. Compression type dead end for small diameter conductor has become popular mainly because of its superiority in Electrical conductivity. These are very suitable for AAC, AAAC & ACSR conductor of small diameter. This installation can be done by mechanical crimper having provision for changing dies suitable for hexagonal crimping. While for AAC and AAAC hand mechanical crimper can be used upto a conductor diameter of 16 mm, for ACSR it is not recommended above 14 mm size.

 

The compression type Dead end assemblies represent the best technical solution for the High Voltage Transmission Lines both from mechanical and Electrical Point of view for the  following reasons :

 1.      The Dead end assembly has breaking load very close to the rated conductor    strength .  RUL guarantee ultimate strength equivalent to 95% ofthe Breaking strength of the conductor.

2.      The Electrical resistance of the assembly when duly compressed on conductor is less than 75% of the resistance of the equivalent length of conductor.

 3.      The Corona and Radio Interference characteristics are equal or better than those of the conductors.

 

Earthwire dead ends are supplied with attachment fittings 'D' Shackles or Clevis.

For voltage of 380 kV or above corona rings are supplied normally made of aluminiun alloy.

 

The values for radio interference voltage and corona requirements of the protections are always kept below the normal internationally specified limits.

'U' bolts, cross arm straps, ' D' shackles etc. are supplied  In galvanized steel to suit all types of cross arms, tower hangers and plates. Standard mechanical rating are 7000 lbs, 9000 lbs, 12000 lbs, 15000 lbs, & above . Special requirements are available on request.

In galvanised steel bar, flame cut steel, forged steel for all requirements and to match above fittings.

 

Clevis eyes & clevis clevises available in both parallel and perpendicular directional arrangement, in galvanised malleable iron.

Large & small steel head forged pins & stay tighteners are available, galvanized, as per British Standard specifications.

To achieve a co-ordinated  Electrical and Mechanical performance to suit system requirement standard insulator Hardware Assemblies have been designed. Some of these standard designs illustrated in this page have been incorporated in the designs through years of technical research and practical applications.

 

The designs incorporate following three principle features:

1.      High Mechanical reliability and flexibility of movement.

2.      Adequate High Voltage Electrical characteristics.

3.   Fatigue free performance under wind induced vibration condition.

 

Single conductor assemblies are principally used upto 220KV.Twin Bundle  systems are popular for upto 400KV system. Triple conductor configuration has been used extensively  mainly in 500KV system. Quadruple conductor bundle system has mainly been used for 750KV lines. However , for lower system voltage use of bundle conductor is necessary where higher ampacity is demanded. For example for both 132KV and 220KV , twin bundle system has been used extensively and for 400KV Quad system has been used in many countries.

 

Because of varied nature of terrain and environment conditions, quite often high mechanical strength rating and electrical creepage is desired in the string designs. The demand of various utilities differ even from project to project and as such there is great necessity of  offering suitable designs for specific requirements. RUL has necessary technical infrastructure to design, develop and test strings designs for customer satisfaction.

To achieve a co-ordinated  Electrical and Mechanical performance to suit system requirement standard Insulator Hardware Assemblies have been designed. Some of these standard designs illustrated in this page have been incorporated in the designs through years of technical research and practical applications.

 

The designs incorporate following three principle features:

 1.      High Mechanical reliability and flexibility of movement.

2.      Adequate High Voltage Electrical characteristics.

3.   Fatigue free performance under wind induced vibration condition.

 

Single conductor assemblies are principally used upto 220KV.Twin Bundle systems are popular for upto 400KV system. Triple conductor configuration has been used extensively  mainly in 500KV system. Quadruple conductor bundle system has mainly been used for 750KV lines. However , for lower system voltage use of bundle conductor is necessary where higher ampacity is demanded. For example for both 132KV and 220KV , twin bundle system has been used extensively and for 400KV Quad system has been used in many countries.

 

Because of varied nature of terrain and environment conditions, quite often high mechanical strength rating and electrical creepage is desired in the string designs. The demand of various utilities differ even from project to project and as such there is great necessity of  offering suitable designs for specific requirements. RUL has necessary technical infrastructure to design, develop and test strings designs for customer satisfaction.

Socket Clevis are supplied in galvanized forged steel to British Standard specifications to socket sizes 11 mm, 16 mm, 20 mm, 24 mm specifications.

 

Socket Clevis normal type , horn holder & ring holder and other types are available.

 

Socket designations to suit other International specifications ANSI, DIN, IEC and ISO standards are available.

 

Various Mechanical ratings are available to suit insulator units. Other International standard fittings on request.

 

Socket Clevis are supplied for Yoke fittings & dead and eye fittings in various ranges.

Socket eyes are supplied in galvanized forged steel British Standard specification standards socket sizes11 mm, 16 mm, 20 mm ,24 mm.

 

Socket eyes normal, horn holder & ring holder and all other types are available.

 

Socket designations to suit other International specifications ANSI, DIN, IEC and ISO standards are available.

 

Various Mechanical ratings are available to suit insulator units. Other International standard fittings on request.

Socket Link is supplied in galvanized forged steel British Standard specification standards socket sizes 11 mm, 16 mm, 20 mm ,24 mm.

 

Socket designations to suit other International specifications ANSI, DIN, IEC and ISO standards are available.

 

Various Mechanical ratings are available to suit insulator units. Other International standard fittings on request.

 

Socket Links are supplied for  dead and eye fittings in various ranges.

Bolted tension clamps are available in  Aluminium alloy or malleable iron for all conductor & earthwire sizes. Compression type clamps are recommended for higher strengths requirements .

 

Socket ended clamps are also available also for sizes upto 100 sq.mm.

 

Higher Slip strength clamps are also available.

RUL offers complete range of envelope design clamps from 6 mm dia to 55 mm diameter conductor. Clamp bodies and keeper pieces are cast in high strength copper free Al-Si Alloy and are also made in other alloys , heat-treated depending upon strength requirement. The U-bolt and clevis pins are of galvanized steel while split pins are of either brass or stainless steel. These clamps offer minimum power loss and heating due to hysteresis effect at higher currents.

 

Suitable socket / clevis eye are available as mating fittings.

 

Clamps are available to suit all sizes of conductors and Earthwires in various designs in all ranges.

 

Slip strength ratings approximate upto 30% ultimate strength of ACSR.

Available in galvanized forged steel for different range settings, take off sizes and mechanical strengths.

 

Link, Eye or  Clevis ended arrangement available singly or as combinations.

 

Sag adjuster plates on request.

Twisted Shackles are supplied in galvanized forged steel in various strength requirements.

 

Various sizes , mechanical ratings are available to suit insulator units.

U-Bolts are supplied in galvanized steel, fabricated in  various lengths. sizes and mechanical ratings to suit customer requirements.

Yoke plate and Sag Adjuster play very important in the design of suitable insulator strings. Yoke Plates are used for strain equalising of insulator string as well as spacing of sub- conductor . Upto 220KV single conductor system for important locations like Highway crossing. River crossing, Railway track crossing, dual string tension and suspension arrangements are used and the total load is equalised by suitable yoke design. Normally upto 220KV the spacing is 330 mm whereas for UHV lines where there is necessity of creating required sub-conductor spacing the applicable gaps are 400 mm, to 500mm. For special application of open profile insulators having large diameter it may be necessary to increase the sub-conductor spacing upto 600mm.

 

Various types of Yokes and Sag adjustment devices are illustrated in the above photographs and are not exhaustive. Provision  are made in the yoke devices to facilitate hot line maintenance.