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iTOWERS Designer (Design Procedure

)

Before starting iTOWERS Designer program, prepare the following technical specifications ready so that you do
not have to look for data when you have to input the parameters.

(Write appropriate units along with the values)

Project Details:
============

Title :
Work Order No. :
Client :

Voltage :
Configuration :
No. Of earth-wires :
Tower Type :

Angle of Deviation (Min-Max) :

Technical Specifications:
===================
Material Stresses:
Steel
Grade : MS HT SHT
Yield Stress > 16mm :
Yield Stress < 16mm :
Bearing Stress :

Bolts Dia 1 Dia 2 Dia 3
Grade :
Shear Stress :
Bearing Stress :

Sag-Tension Calculations:

Basic Span (m) :
Properties of conductor / ground wire
Conductor Groundwire

Eg.,: Title : ACSR - MOLE
Ult. Tensile Strength : 405.00
Self Weight : 0.043
Dia. Of Conductor : 0.4500
X-Sectional Area : 0.1237
Elastic Modulus : 0.8056E+06
Coef. Thermal Expansion : 19.10E-06
Wind Pressure :
Gust factors :
Drag Coeff :
Shape Factor :

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4. 5. 9. 2. iTOWERS Designer (Design Procedure) Climatic conditions: Amb. Sag : Sections sizes to be used in the tower design: Country Code : INDIA Size MS HT SHT Eg. 7. 6. Limiting percentage of Gw sag to Cond.: 45x45x5 yes no no 50x50x5 yes no no 75x75x5 yes yes no 45x30x5 yes no no Loads Generation: Span Details Normal Broken Wind Span : Weight Span (max) : Weight Span (min) : Tension Values Conductor Groundwire Reliability : Security : Safety : Anti cascading : Stringing : Other Loads: GW Clamp : Insulator weight : Erection Loads : Insulator Details: Type 1 Type 2 Type 3 (Suspemsion/ Tension) (Pilot Insulator) (V-String) Length (max) : Length (min) : Dia of the disc : Number of discs : Shape Factor : Wind Pressure : Gust response fac. Ice thk (if any) Wind FOS (cond) FOS(GW) 1. 8. 10. : Drag Factor : Page 2 of 7 . Temp Additional Temp.. 3.

0 Over Load Factors : Reliability : Security : Safety : Anticascading : Stringing : Design: Design Code : Design Requirements : Member class parameters: Name stress ratio Limiting L/r Min.2 0. Thickness Comp Tension Comp Tension Eg..85 30 1.99 120 375 5 mm Redundant design: 1.: IS 802-1995 values on tower Soilidtity Ratio Value 0.26 80 2.1 3..96 40 2.3 2.2 2.4 2. Main Legs 0.4 0.5 0.9 0.13 60 2.: IS 802 -1995 values on tower Height Factor 10 1.6 0.5 2. Bending check Load : Angle : Other technical information you would like to note: Page 3 of 7 .31 500 2. % of connected Member Force : 2.98 0.07 50 2..2 70 2. iTOWERS Designer (Design Procedure) Conductor Groundwire Tower Body Wind Pressure : Surface Factor : Gust Response Factors (Table and Values) Eg.31 Drag Coefficients (Table and values) Eg.70 20 1.05 3.

OR Generate the required patterns and update the library... Geometry Generation: ================= Step 1:Draw the rough sketch of the tower on a white paper (with all views and dimensions clearly indicated) Note: In case of a new tower design draw the outer profile of the tower (which is extracted after performing the clearance calculations) with all dimensions and select some appropriate patterns from the pattern library. 7.0m. as required. 3. Step 2:Identify the required patterns from the pattern library and mark them in the above drawing.0m Leg Combinations: Eg.5 1.5m. iTOWERS Designer (Design Procedure) Step by step Design procedure in iTowers Tower specifications: ================ Specify the tower specifications input from the data collected from project specifications data.5m. 9m.5 1. (Go through the movie file in ‘Help-working with iTowers Designer (Movie)-Specifications’ for input procedure of Tower specifications) Sag-Tension Calculations: ==================== Step-1: After giving the input for tower specifications. Or Incase of design of a new tower select appropriate patterns available in the library and after the initial design.5m. Note: In case of design checking of an existing tower identify the exact patterns from the pattern library. 9. 4. mark the closest pattern.5 3 3 3 3 4. Step 3: identify how many extensions are required: No.5 7. Note: In case of design checking of an existing tower compare the results to the existing calculations.0m.: Equal Edge-1 Edge-2 Edge-3 Edge-4 1. patterns can be changed or create the required patterns. 12m No.: 3m. 6. 6m.5 4.5 7.5 4. of Body entensions: Eg.5 7.5 Page 4 of 7 . execute the module for sag-tension calculations. If the required patterns are not available.5 1. Of Leg Extensions: 1.5 4.5 6 6 6 6 7. If all the patterns are not available create the required patterns in the pattern library. Step-2: Check the results in ‘Tower contour generation’ through view reports.

: Unequal 1. . Step 5: View drawings using "View Drawings" Preliminary design: =============== Step 1: Import program generated Effective Length data.. Step 2: Feed the data required for other loads such as wind loads. Step 4: Extract the drawings with member group and check the member groups... (Go through the movie file in ‘Help-working with iTowers Designer (Movie)-Predesign’ for Predesign input) Step 2: With the help of the drawing extracted above check the eff. Step 3: Select the section of extraction (after tower assembly & Validation) (Go through the movie file in ‘Help-working with iTowers Designer (Movie)-Single line drawing’ for single line drawings input) Step 4: Execute the Single Line Drawings module. keep them ready for inputting the loads using "Inputs-> Loads -> Data for External Load cases" or using Inputs-> Loads-> Data for Auto Loads -> Load Trees" OR Step 1: Feed the input data required for Automatic Loads generation as per IS 802 or IEC 826. Step 5: Using the tower template. self weight using Inputs -> Loads -> Data for External Load cases. Step 4:note the elevation at which the cross arm gets connected and the heights of the cross arms. iTOWERS Designer (Design Procedure) 9 9 9 9 Eg.5 .. The program loads the input for drawings Step 2: Check the data generated (elevations / sectional views / dimensions)..5 3 1.5 4. Step 3: Execute the Predesign Module. Single Line Drawings: ================= Step 1: Open the input module for single line drawings. (Go through the movie file in ‘Help-working with iTowers Designer (Movie)-Tower model generation’ for geometry generation of tower) Step 6: Execute Tower Assembly and Validation module Step 7: Extract the drawings with member number and check the drawings (dimensions/ patterns/ views) See below how to extract the drawings.5 3 1.5 4..5 1. compete the tower geometry. Page 5 of 7 . Loads Generation Module: ===================== Step 1: If the load trees available.. lengths data. (Go through the movie file in ‘Help-working with iTowers Designer (Movie)-Loads’ for Loads input) Step 4: Execute Loads Generation module Step 5: Check the output thoroughly before you proceed further.

(Go through the movie file in ‘Help-working with iTowers Designer (Movie)-Analysis’ for Analysis input) Step 7: Execute the 3D Space Truss Analysis module Step 8: Check the output like whether the load combinations and the corresponding factors have been considered appropriately. The program load the inputs for drawings (Go through the movie file in ‘Help-working with iTowers Designer (Movie)-Load Trees’ for Load tree drawings input) Page 6 of 7 . Step 5: View drawings using "View Drawings" Load Trees: ========== Step 1: Open the input module for Load Trees. Step 4: Select the report options as required. redundant member forces b. Single Line Drawings (Final for submission): ================================== Step 1: Open the input module for single line drawings. (Go through the movie file in ‘Help-working with iTowers Designer (Movie)-Redesign’ for Design input) Note: In case of design checking of an existing tower specify the section sizes for all the member groups as per the existing design drawing. go through the movie file in ‘Help-working with iTowers Designer (Movie)- Redesign-Forcing section size and number of bolts’ Step 5: Execute Design module. thoroughly before you proceed further. Design: ======= Step 1: Input the data for additional design requirements like a. (Go through the movie file in ‘Help-working with iTowers Designer (Movie)-Single line drawing’ for single line drawings input) Step 4: Execute the Single Line Drawings module. Step 3: Select the section of extraction. Analysis Module: ============= Step 1: Load the program generated Load Combinations Step 2: Check the hypothesis data for over load factors Step 3: Check the association of hypo number for each load combination. iTOWERS Designer (Design Procedure) Note: In case of design checking of an existing tower compare the load calculation results to the existing calculations and check whether the results are matching after three cycles. Step 6: Print and check the output files after three cycles. The program load the input for drawings Step 2: Check the drawings (elevations / sectional views) data and create drawings data for wind load application and distribution drawings. (pls. Note: In case of design checking of an existing tower check the design adequacy of all the member groups from the design reports generated by the program after three cycles. Step 4: Associate the wind load cases for different tower combinations Step 5: Feed the input data for displacement drawings (optional) Step 6: Select the required report options. Note: In case of design checking of an existing tower compare the analysis results like Support reactions or Member forces to the existing results after three cycles. bending check Step 2: Import program generated panel data for reports for panel wise design report. Step 3: Check the effective length data generated by the program.

Run the job for 3 cycles. This is to take the revised section sizes into consideration for wind loads. Page 7 of 7 . iTOWERS Designer (Design Procedure) Step 2: Execute the module for Load Trees generation. self weight and analysis. Step 3: View Load Trees using "View Drawings" 2nd & 3rd Cycle: ============ After running the job for one complete cycle (from sag-tension cal's to design module) re-run the job from loads to design module. Analysis and Design and compare the results with the existing tower incase of an existing tower design. Now go through all the reports generated by the program after Loads. In case of a new tower design now the results are final for further tower engineering.