Task description: conductor type (weight/kg per meter), maximum span length, steep grades/obstacles, number of sheaves/bends, whether you’ll do tower erection/sagging or only stringing.
Peak line tension required (account for conductor weight, wind/ice if applicable, plus friction from blocks/sheaves).
Desired pulling speed (m/min or m/s) — faster pulls need more power.
Rope/drum requirements: rope length to handle the longest pull, drum diameter that won’t crush the rope, drum layers and rope capacity.
Safety factor and duty cycle: e.g., select SWL >= 1.5–2× (or more for critical lifts) of calculated max pull and confirm continuous vs intermittent duty.
Use SI units for clarity.
Line pull (force): FFF in newtons (N). If you have kN, multiply by 1000.
Drum torque required: T=F×rT = F times r (Newton-metres), where rrr = drum radius (m).
Mechanical power at drum: Pdrum=F×vP_{drum} = F times v (watts), where vvv = rope speed (m/s).
Engine power (accounting inefficiency):
Pengine=PdrumηP_{engine} = frac{P_{drum}}{eta}where ηetaη is overall drivetrain efficiency (typical 0.6–0.85 depending on gearbox/hydraulics). Convert W → kW by dividing by 1000 (or to HP: 1 HP ≈ 0.746 kW). For hydraulic motor sizing you’ll do similar torque & speed calcs.
Assumptions (example overhead stringing):
Peak required line tension F=20 kNF = 20 text{kN} → 20,000 N (includes friction & margin).
Desired rope speed v=1 m/sv = 1 text{m/s} (≈ 60 m/min).
Drum radius r=0.25 mr = 0.25 text{m} (500 mm diameter).
Overall drivetrain efficiency η=0.7eta = 0.7.
Calculations:
Pdrum=F×v=20,000×1=20,000 W=20 kW.P_{drum} = F times v = 20{,}000 times 1 = 20{,}000 text{W} = 20 text{kW}.
Pengine=20 kW/0.7≈28.6 kW.P_{engine} = 20 text{kW} / 0.7 approx 28.6 text{kW}. → choose an engine with margin: pick ~35–40 kW (≈ 47–54 HP) depending on duty cycle and cold starts.
Drum torque: T=20,000×0.25=5,000 Nm.T = 20{,}000 times 0.25 = 5{,}000 text{Nm}. Gearbox/hydraulic motor and brake must supply this torque at operating speeds.
Capacity margin: pick winch rated at least 1.5–2× your calculated peak pull for overhead stringing (industry practice). For recovery or critical lifts use larger factors.
Drive type: diesel/petrol engine driving a hydraulic circuit (hydraulic winch) is common — gives smooth variable speed and high torque at low speed. Electric engines are used when site power is available.
Brake & control: fail-safe mechanical or hydraulic braking; variable speed control (fine control at low speeds); remote control option for safety.
Drum & rope: choose drum diameter ≥ recommended minimum for rope bending radius; provide enough drum length/layers to store full pull length; use rope with appropriate construction and safety factor. Follow rope selection & SWL standards.
Capstan / split-drum options: for some conductor types a capstan or split-drum helps control speed and rope layering; check manufacturer catalogues for build options.
Environment & mounting: weatherproofing, dust/water ingress rating, anchoring points for winch base, skidding/mobility needs. Safety & standards
Comply with applicable standards for wire rope and lifting/pulling equipment (examples: OSHA provisions for wire rope, EN standards for winches). Ensure certified SWL, inspection schedule, operator training and emergency stop systems.
Max continuous and peak line pull required (N or kN) + desired rope speed.
Drum diameter & rope length needed.
Requested duty cycle (how many minutes/hr under load).
Environment (temperature, dust, wet, offshore?).
Required controls (remote, auto-tensioning, tension monitoring).
Standards/certifications required.
Task description: conductor type (weight/kg per meter), maximum span length, steep grades/obstacles, number of sheaves/bends, whether you’ll do tower erection/sagging or only stringing.
Peak line tension required (account for conductor weight, wind/ice if applicable, plus friction from blocks/sheaves).
Desired pulling speed (m/min or m/s) — faster pulls need more power.
Rope/drum requirements: rope length to handle the longest pull, drum diameter that won’t crush the rope, drum layers and rope capacity.
Safety factor and duty cycle: e.g., select SWL >= 1.5–2× (or more for critical lifts) of calculated max pull and confirm continuous vs intermittent duty.
Use SI units for clarity.
Line pull (force): FFF in newtons (N). If you have kN, multiply by 1000.
Drum torque required: T=F×rT = F times r (Newton-metres), where rrr = drum radius (m).
Mechanical power at drum: Pdrum=F×vP_{drum} = F times v (watts), where vvv = rope speed (m/s).
Engine power (accounting inefficiency):
Pengine=PdrumηP_{engine} = frac{P_{drum}}{eta}where ηetaη is overall drivetrain efficiency (typical 0.6–0.85 depending on gearbox/hydraulics). Convert W → kW by dividing by 1000 (or to HP: 1 HP ≈ 0.746 kW). For hydraulic motor sizing you’ll do similar torque & speed calcs.
Assumptions (example overhead stringing):
Peak required line tension F=20 kNF = 20 text{kN} → 20,000 N (includes friction & margin).
Desired rope speed v=1 m/sv = 1 text{m/s} (≈ 60 m/min).
Drum radius r=0.25 mr = 0.25 text{m} (500 mm diameter).
Overall drivetrain efficiency η=0.7eta = 0.7.
Calculations:
Pdrum=F×v=20,000×1=20,000 W=20 kW.P_{drum} = F times v = 20{,}000 times 1 = 20{,}000 text{W} = 20 text{kW}.
Pengine=20 kW/0.7≈28.6 kW.P_{engine} = 20 text{kW} / 0.7 approx 28.6 text{kW}. → choose an engine with margin: pick ~35–40 kW (≈ 47–54 HP) depending on duty cycle and cold starts.
Drum torque: T=20,000×0.25=5,000 Nm.T = 20{,}000 times 0.25 = 5{,}000 text{Nm}. Gearbox/hydraulic motor and brake must supply this torque at operating speeds.
Capacity margin: pick winch rated at least 1.5–2× your calculated peak pull for overhead stringing (industry practice). For recovery or critical lifts use larger factors.
Drive type: diesel/petrol engine driving a hydraulic circuit (hydraulic winch) is common — gives smooth variable speed and high torque at low speed. Electric engines are used when site power is available.
Brake & control: fail-safe mechanical or hydraulic braking; variable speed control (fine control at low speeds); remote control option for safety.
Drum & rope: choose drum diameter ≥ recommended minimum for rope bending radius; provide enough drum length/layers to store full pull length; use rope with appropriate construction and safety factor. Follow rope selection & SWL standards.
Capstan / split-drum options: for some conductor types a capstan or split-drum helps control speed and rope layering; check manufacturer catalogues for build options.
Environment & mounting: weatherproofing, dust/water ingress rating, anchoring points for winch base, skidding/mobility needs. Safety & standards
Comply with applicable standards for wire rope and lifting/pulling equipment (examples: OSHA provisions for wire rope, EN standards for winches). Ensure certified SWL, inspection schedule, operator training and emergency stop systems.
Max continuous and peak line pull required (N or kN) + desired rope speed.
Drum diameter & rope length needed.
Requested duty cycle (how many minutes/hr under load).
Environment (temperature, dust, wet, offshore?).
Required controls (remote, auto-tensioning, tension monitoring).
Standards/certifications required.
