MEGATRO 400KV GUYED VEE SUSPENSION TOWER
This refer to light guyed suspension tower, and also named Guyed VEE tower, which occupied less space and installed by steel guyed stay wires for high voltage AC and DC power transmission line systems. This type of tower is widely used for overseas client, and our MEGATRO design them and provide tower loading & geometry and other documents. This tower also named lattice guyed single column delta structure. At top bridge there is one phase twin conductor, and left two phase conductors at lower both cross-arms end, two earth wire at top peak of tower.
Some of their features as follow:
| 1 |
Line details - Circuit (SC) & KV. |
SC, 400 KV |
| 2 |
Number of phases. |
3 |
| 3 |
Tower shape |
Guyed V type configuration |
| 4 |
Tower details |
Wind span |
Weight Span |
Uplift span (m) |
| |
430m |
305m |
0 |
| 5 |
Grade of steel to be used for towers and bolts |
Mild steel Q235B and high strength yield steel Q345B; ASTM A394 type 0 and 1 |
| 6 |
Angle of line |
0 degree angle towers |
| 7 |
Details Determining tower dimensions |
Nominal design span |
400m |
| Final phase conductor sag at 50 for design span |
12 |
| Minimum clearance form lowest phase conductor to earth |
8.5 |
| Height of lowest phase conductor attachment point above earth |
20.5 |
Minimum clearance from live metal to earthed metal and guy wires
A. under still air conditions
B. Under 15°swing conditions to tower steelworks
C Under 15°swing conditions to guy wires
D under 55°swing conditions to tower steel work and guy wires
|
3.2
3.2
2.7
1.0 |
| 8 |
Load factor for wind speed |
1.1 |
| Load factor for wind pressure |
1.21 |
| Conductor attachment height |
20.5m |
| 9 |
Right of way |
46m |
| 10 |
Conductors Type ( ACSR/AAAC/etc) |
QUAD WOLF ACSR 30/7/2.59 |
| 11 |
Conductor - Single/twin/quad/hexa |
Twin at middle and single at both side |
| 12 |
Earth-wire |
OPGW (two ×19/2.65) |
| 13 |
Insulators. |
400 KV post insulators, 120KN suspension |
| 14 |
Foundations |
Concrete, with stub embedded into foundation |
| 15 |
Factor of safety. |
2 |
| 16 |
Environmental condition of area (Temp). |
Design Ambient Temperature 35 DegC |
| 17 |
Tower Height. |
32-48 Mtr. (Subject to approval ) |
| 18 |
Design Code |
ASCE Manual No -72, IS 802 (part I & part II)-1997, IS 5613 (part I & part II), transmission line manual (publication no -268 ) |
| 19 |
Type of Soil (Normal / Black cotton) |
Deleterious, dusty, sandy silts and tills, |
Remark: above technical data only references for our client, we can design every type for our overseas clients.
Our 400KV guyed VEE suspension tower is designed and supported by guyed stay wire to reduce tower loading, and reduce space and rural land occupied. This tower belongs to suspension type, and OPGW on the top of tower.
Also this 400KV guyed VEE suspension tower, which reduce the space occupied by tower base are being used. Also this tower designed also considered aesthetic integration of transmission line to surrounding environment.
Since 2004, MEGATRO has been manufacturing every type of lattice transmission tower & tapered steel poles for utility applications. MEGATRO pioneered the development of transmission tower, telecom tower, substation, and other steel structure and was also at the forefront in the design of Transmission tower. MEGATRO has a complete staff of professional engineering personnel trained in the PLS Pole program and three different manufacturing processes for producing steel towers, poles and other supports. We utilize the latest versions of PLS-CADD, PLS-POLE, TOWER, AutoCAD and other CAD software.
Our MEGATRO had professional design engineer to provide every type of tower loading with detailed drawings for our client. The 400KV guyed VEE suspension tower structure shall be designed according to load combinations given as per IEC 61936-1 and as illustrated below:
Normal loads
1 Dead weight load
2 Tension load
3 Erection load
4 wind load
Exceptional loads
1 Switching forces
2 short-circuit forces
3 Loss of conductor tension
4 Earthquake forces
MEGATRO is one of the few manufactures who assemble a face of 400KV guyed VEE suspension tower structure. This attention to quality may not be the cheapest process but it does insure every tower meets our high standards of quality. And it helps to reduce on-site construction cost due to mismatched assemblies. MEGATRO 400KV guyed VEE suspension tower structure systems can accommodate a variety of cross-arm and other accessories. After fabrication 400KV guyed VEE suspension tower are delivered to the galvanizing facility to be Hot DIP Galvanized. Towers are processed through the facility by Caustic Cleaning, Pickling, and then Fluxing. These strict procedures insure years of maintenance free towers. Even we take secondary finish for client again, which as duplex surface treatment.
Other information:
Availability size: Based on the customer's requirements.
Material: Chinese material or as per clients requirement
Package: Both parties discuss before delivery
Port of Loading: Qingdao Port
Lead Time: One month or based on the customer's needs
Fabrication standard: Chinese Standard or other standard which client accepted
Steel grades
Tower body: Chinese steel Q345B, which same to ASTM A572 GR50
Other webs, bracing and not stress plate and angle steel: Chinese Q235B, which same to ASTM A36
Plates: Chinese steel Q235B, which same to ASTM A572 GR50
Bolts: Chinese grade 6.8 and 8.8, which similar to ASTM A394
A) Dimension and tolerance for angle are according to GB/T1591-1994, similar to EN 10056-1/2
B) Hot DIP galvanization in accordance with GB/T 13912-2002, which similar to ASTM A 123
C) The welding will be performance in accordance with AWS D1.1 or CWB standard
If any special requirement, we can design and discuss with client.
General Fabrication Requirements
Here is general fabrication requirements for our transmission tower; however, both parties must discuss all drawings and confirm all shop drawings, technical specification, and which standard to conform.
Before mass production, we must received all signed approved shop drawings and technical documents from our client.
Our Fabrication shall be in strict accordance with detail Drawings prepared by the Contractor and approved by the Engineer. Fabrication shall begin after the approval of the shop assembly and tests.
Shearing
Shearing and cutting shall be performed carefully and all portions of the work which will be exposed to view after completion shall be finished neatly. Manually guided cutting torches shall not be used.
All material over 13 (or 12) mm thick shall be cold sawn or machine flame cut.
Cropping or shearing shall be allowed for material thickness of 13 mm or less.
Flame cutting of high yield steel shall be preceded by a slight preheat operation by passing the cutting flame over the part to be cut.
All flame-cut edges shall be ground clean.
Bending
Bending shall be carried out in such a manner as to avoid indentation and surface damage. All bending over 5o, or high yield steel, shall be performed while the material is hot.
Welding
No welding shall be done unless prior approval has been obtained from the Engineer.
Welding shall not be allowed at tower attachment points for conductor, shield-wire, insulators or associated assemblies or brackets.
Sub-punching
All holes in structural steel less than 10 mm thickness may be punched to full size unless otherwise noted on the approved Drawings. Holes shown on the Drawings as drilled holes and all holes in structural steel 10 mm or more in thickness and tension members of cross-arms shall be drilled or sub-punched and reamed.
All holes shall be clean cut and without torn or ragged edges. All burrs resulting from reaming or drilling shall be removed. All holes shall be cylindrical and perpendicular to the member.
Where necessary to avoid distortion of the holes, holes close to the points of bends shall be made after bending.
Punching
For punching to full size, the diameter of the punch shall be 1.0 mm larger than the nominal diameter of the bolt, and the diameter of the die shall not be more than 1.5mm larger than the diameter of the punch. For sub-punching, the diameter of the punch shall be 4 mm smaller than the nominal diameter of the bolt, and the diameter of the die shall be not more than 2 mm larger than the diameter of the punch. Sub-punching for reamed work shall be such that after reaming no punch surface shall appear in the periphery of the hole.
Hole Size
Where holes are reamed or drilled, the diameter of the finished hole shall be not greater than the nominal diameter of the bolt plus 1.0 mm.
Accuracy
All holes shall be spaced accurately in accordance with the Drawings and shall be located on the gauge lines.
The maximum allowable variation in hole spacing from that indicated on the Drawings for all bolt holes shall be 0.8 mm.
Fabrication Tolerances
A specification for tolerances shall be submitted for approval by the Engineer prior to commencement of fabrication.
Bolt List
A complete list of bolts showing their lengths and the members, which they are to connect shall be given on the erection diagrams.
Locking Devices
Locking devices for tower bolts will not be required, but point punching shall be performed.
Anti-theft Fasteners
Appropriate anti-theft fasteners for example Huck-bolting shall be applied on all the towers up to the level of anti-climbing devices, to prevent theft of tower members.
Piece Marks
All pieces shall be stamped before galvanizing with the piece marks shown on the erection Drawings, with the marking not less than 20 mm high placed in the same relative location on all pieces. The marking shall be plainly visible after galvanizing.
Galvanizing
All material shall be hot-dip galvanized after fabrication in accordance with the latest revision of GB/T 13912-2002 or ASTM Specification A 123.
Material that has been rejected because of bare spots or other coating defects shall either be stripped and re-galvanized, or the uncoated areas shall be recoated by an approved method.
All plates and shapes which have been warped by the galvanizing process shall be straightened by being re-rolled or pressed. The material shall not be hammered or otherwise straightened in a manner that will injure the protective coating.
Approval shall be secured from the Engineer if galvanizing is done outside of the Contractor's plant.
All galvanized steelwork shall be protected against white storage stain by using an approved dichromate solution treatment immediately following galvanizing.
APPLICABLE STANDARD AND CODES
All towers manufactured and design shall be generally in accordance with latest revision of the following standards except where specifically directed otherwise.
General
IEC 60826 - Design criteria of overhead lines
IEC 60652 - Loading tests on overhead line structures
ISO 1459 - Metallic coatings - Protection against corrosion by Hot Dip Galvanizing
ISO 1461 - Hot dip galvanized coatings on fabricated iron and steel articles
ISO 12944 - Paint coatings, corrosion protection, and structural steelwork
ISO 898-1 - Mechanical properties of fasteners. Part 1-Bolts, Screws and studs
ISO 630 - Structural Steels - plates, wide flats, bars, sections and profiles
ISO 657 - Hot rolled structural steel plates tolerances on dimensions and shape
ISO 7411 - Hexagon Bolts for high strength structural bolting with large width across flats
ISO 657-5 - Hot rolled Structural Steel Sections equal and unequal leg angles
ISO 7452 - Hot rolled structural steel plates tolerances on dimensions and shape
BS EN 50341-1 - Overhead electrical lines exceeding AC 45kV -General Requirements
BS 8004 - Code of Practice for Foundations
BS 8110 - Structural use of concrete
ANSI10-97 - Design of latticed steel transmission structures
IEC 60050 (151) International Electro-technical Vocabulary
Part 51 Electrical and Magnetic Devices
IEC 60050 (601) Chapter 601: Generation, transmission and distribution of electricity-General
IEC 60050 (601) Chapter 601: Generation, transmission and distribution of electricity-Operation
IEC 60059 IEC standard current ratings
Chinese Standard
| No |
Code |
DESCRIPTION |
| 1 |
GB/T2694-2003 |
Power Transmission line Steel tower - Technical requirements for manufacturing |
| 2 |
JGJ81-2002 |
Technical specification for welding for steel structure of building |
| 3 |
GB9787-88 |
Measuring and allowable tolerance for hot-rolled equal angle |
| 4 |
GB709-88 |
Measuring and allowable tolerance for hot-rolled plate and strip |
| 5 |
GB/T699-1999 |
Quality Carbon Structural Steel |
| 6 |
GB/T1591-1994 |
Low alloy high strength structural Steel |
| 7 |
GB700-88 |
Carbon Structural Steel |
| 8 |
GB222-84 |
Method of sampling steel for determination of chemical composition and permissible variations |
| 9 |
GB/T228-2002 |
Method for Tensile testing of metals |
| 10 |
GB/T232-1999 |
Method for Bending test of metals |
| 11 |
GB/T5117-1995 |
Carbon Welding Rod |
| 12 |
GB/T5118-1995 |
Low Alloy Welding Rod |
| 13 |
GB/T8110-1995 |
Welding wires for gas shielding arc welding of carbon and low alloy steels |
| 14 |
GB/T10045-2001 |
Carbon steel flux cored electrodes for arc welding |
| 15 |
JB/T7949-1999 |
Weld outer dimensions for steel construction |
| 16 |
GB50205-2001 |
Test Standard for Acceptance of Steel Structure |
| 17 |
GB/T470-1997 |
Zinc Ingot |
| 18 |
GB3098.1-2000 |
Mechanical properties of fasteners-Part 1:Bolts, screws and studs |
| 19 |
GB3098.2-2000 |
Mechanical properties of fasteners-Part2: Nuts, and thread |
| 20 |
GB3098.3-2000 |
Mechanical properties of fasteners-Part3: Fastening screw |
| 21 |
GB/T5780-2000 |
Helical Bolts Grade C |
| 22 |
GB/T41-2000 |
Helical Nuts Grade C |
| 23 |
GB/T90-2002 |
Flat Washer Grade C |
| 24 |
GB/T13912-2002 |
Metal Coating, Technical Requirement and Test Method for Hot-dip galvanized Metal Parts |
American Standards:
| Standard |
Description |
| ASTM A6/A6M |
Standard specification for general requirements for rolled structural steel bars, plates, and sheet piling. |
| ASTM - 6 |
- General Requirements for delivery of Rolled Steel Plates, Shapes, sheet Piling Bars for structural used |
| ASTM A36/A36-M-97a |
Standard specification for Carbon structural steel |
| ASTM A123 / A123M-02 |
Standard specification for Zinc (Hot-Dip Galvanized) Coatings on iron and steel products |
| ASTM A143 / A143M-03 |
Standard Practise for Safeguarding Against Embitterment of Hot-Dip Galvanized Structural Steel Products and Procedure for Detecting Embitterment |
| ASTM A153/ A153M-05 |
Standard specification for zinc coating (Hot-Dip) on iron and steel hardware |
| ASTM A - 194 |
- Grade for bolt |
| ASTM A239 |
Standard practice for locating the thinnest spot in a zinc (Galvanized) Coating on Iron or Steel Articles |
| ASTM A242 |
Standard specification for High-Strength Low-Alloy Structural steel |
| ASTM A307 |
Standard Specification for Carbon Steel Bolts and Studs, 60000 PSI Tensile strength |
| ASTM A370-06 |
Standard Test Methods and Definitions for Mechanical Testing of Steel Products |
| ASTM A325 |
Standard Specification for structural bolts, steel, Heat treated 120/105 ksi minimum tensile strength |
| ASTM A-325 or A-354 |
- Galvanized hexagonal head of connection bolt |
| ASTM A325-97 |
Standard Specification for High-strength Bolts for structural steel Joints |
| ASTM A384 / A384M-02 |
Standard Practise for Safeguarding Against Warpage and Distortion During Hot-Dip Galvanizing of Steel Assemblies. |
| ASTM A394-93 |
Standard Specification for steel Transmission Tower, Bolts, Zinc Coated and Bare |
| ASTMA - 563 |
- Class and size of nuts |
| ASTMA - 572 |
- Chemical composition of steel |
| ASTM A572/A572-97c |
Standard specification for High-Strength Low-Alloy Columbium-Vanadium Structural steel |
| ASTMA - 615 |
- The anchor bolt material |
| ASTM A673 / A673M-07 |
Standard Specification for Sampling Procedure for Impact Testing of Structural Steel |
| ASTM B201 |
Standard practice for testing Chromatic coating on Zinc and Cadmium surfaces |
| ASTM E94-93 |
Standard Guide for Radiographic Testing |
| ASTM E 709-95 |
Standard Guide for Magnetic Particle Examination |
| ASCE Manual 72 |
- Load testing a simple structure |
| ASCE 10-97 |
Standard Design of latticed steel transmission structures |
| AWS D1.1 |
American Welding Society D1,1/D1,1M structural Welding code- Steel |
| ANSI B-182-2 |
Bolts, nuts and washers dimensions |
DIN VDE 0101 - Isokeraunic Level
VDE 0201 - Climatic and environmental conditions
CVDE 0210 - Minimum safety factors under simultaneous working loads
ISO R898 Mechanical Properties of Fasteners
BS EN ISO 1461:1991 - High dip galvanized coatings on fabricated iron and steel articles. Specifications and standards
A) BS 5950: Welding Terms And Symbols
B) BS 729: Hot - Dip Galvanised Coating On Iron And Steel Articles
C) BS 2901: Filler Rods And Wires For Gas Shielded Arc Welding: Part 1 Ferritic Steels
D) BS 3692: ISO Metric Precision Hexagon Bolts, Screws And Nuts
E) BS 4360: Weldable Structural Steel
F ) BS 5135: Metal - Arc Welding Of Carbon And Carbon Manganese Steel
G) BS 5950: Part 1: Code Of Practice For Loading Latticed Tower & Masts
Part 2: Guide To The Background And Use Of Part 1"Code OF Practice For Loading"
Part 3: Strength Assessment of Members
H) DD 133 (1986): Code Of Practice For Loading Latticed Tower & Masts
I) BS 4592 (1987): Part 2: Specification For Expanded Metal Grating Panels
J) BS 4592 (1977): Code Of Practice For Protective Coating Of Iron And Steel Structure Against Corrosion
K) BS 4190: Bracing & Flanged Bolts
L) BS 4190: Rolled Steel sections, Flats & Plates
If any special requirement, we can design and discuss with client.
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MEGATRO 400KV GUYED VEE SUSPENSION TOWER
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