technical of V TYPE TRUNCKBUCKLE
1. Ultimate Tensile Strength (UTS)
1. V-type design adds angular stability and load alignment.
2. UTS verified via mechanical testing (as per IS 2486, ASTM F1145, or DIN 1480).
2. Working Load / Safe Working Load (SWL)
1. SWL is generally calculated with a safety factor of 2.5 to 3 applied to UTS.
I. M12 :
10 – 15 kN
II. M16 :
18 – 25 kN
III. M20 :
30 – 40 kN
IV. M24 :
40 – 55 kN
2. Adequate for guying poles, supporting cross arms, or aligning tensioned wire assemblies.
3. Conductor Diameter Compatibility
1. Turnbuckles do not directly grip conductors, but are installed with stay wires or messenger wires.
2. The eye or jaw ends connect to:
a. Stay rods
b. Eye nuts
c. Guy wire anchors
4. Slip Strength:
1. Key Factors:
I. Left-hand and right-hand threaded rods
II. Locking nuts or jam nuts
III. Thread engagement ≥ 90%
2. Ensures secure tensioning during storms, vibrations, and temperature changes.
5. Temperature Withstanding Capacity:
1. Material retains mechanical properties across extreme weather fluctuations.
2. Ideal for outdoor pole-line use in tropical and high-temperature zones.
6. Corrosion Resistance:
1. To ensure long service life in harsh outdoor conditions, the hardware is hot-dip galvanized (HDG).
2. Complies with ASTM B117 for salt spray/corrosion testing.
7. Impact & Fatigue Strength:
1. Designed to absorb dynamic tension, vibrations, and shocks:
I. Fatigue Load Cycles
>10⁶ at rated SWL
II. Shock Load Resistance
≥ 5× SWL
III. Bending Tolerance
High – due to V-fork design
2. V-Type structure helps in dissipating bending stresses during wind galloping and line sways.
Top 5 Quality Assurance
1. Raw Material Testing
a. Tensile, yield, elongation tests on steel rods (IS 2062 Grade A/B or ASTM A36)
b. Chemical composition testing (spectrometry)
c. Grain size and forging microstructure inspection
2. In-Process Quality Control
a. Dimensional accuracy checked with calipers, thread gauges
b. Torque testing for nuts and threaded portions
c. Welding & forming integrity inspection (if applicable)
3. Routine QA Tests
a. UTS test (UTM or Hydraulic press)
b. Galvanizing test (coating thickness, adhesion)
c. Slip and elongation test under load
d. Corrosion test (salt spray ≥ 500 hrs)
e. Load cycle fatigue test
4. Certifications & Standards
a.Conforms to:
I. IS: 2486 (Part 1 & 2) – for hardware fittings
II. ASTM F1145 / A153 – for mechanical and coating properties
III. DIN 1480 – for turnbuckle dimensional design
5. Supplied with:
I. Mill Test Certificate (MTC)
II. Galvanizing Certificate
III. Type Test Report (optional from CPRI or NABL lab)
IV. Batch traceability tags (Heat No. / Lot No.)