Typical Brake Sizing

Material Unwind Operations

Sizing Specifications
Full roll diameter (in.) (FD) = 6 in.
Core diameter (in.) (CD) = 4 in.
Average Tension (lbs.) (T) = 4 lbs.
Velocity (feet per min.) (V) = 100 fpm

Sizing Formula
Average radius (in.) = (FD+CD) / 4 = (6+4) / 4 = 2.5 in.
Torque (in. lb.) = (T) x Avg. Rad. = 4 x 2.5 = 10 in. lb.

Check Tension Range
Maximum Tension = Torque x 2 / CD (10×2 / 4) = 5 lbs.
Minimum Tension = Torque x 2 / FD (10×2 / 6) = 3.3 lbs.
Slip Watts = Max. Tens. x V / 44.2  (5×100 / 44.2) = 11.3 watts
Specify: Model SMB-12

Coil Wind Operations

Sizing Specifications
Pulley/Nip Roll dia. (in.) (D) = 6 in.
Tension (T) = 6 lbs.
Velocity (V) = 100 fpm

Sizing Formula
Torque (in. lb.) = TxD / 2 = (6×4) / 2 = 12 in. lb.
Slip Watts = TxV / 44.2 = (6×100) / 44.2 = 13.6 watts
Specify: Model SMB-12

If diameter is not predetermined, calculate slip watts and select a unit with a sufficient dissipation rating. Determine maximum diameter of pulley or nip roll using the following equation:  Max. dia. (in.)=(12 in.lb.x2) / 6 lbs. = 4 in.

Material Handling Operations

Motor Horsepower Method
Motor HP = 1/2 HP
Motor RPM = 1750 RPM

Sizing Formula
Torque (in. lb.) = HP x 63000 / RPM
1/2 x 63000 / 1750 = 18 in. lb.
Specify: Model SMB-60

Tightening Operations

Sizing Specifications
Slip RPM = 500 RPM
Torque = 8 in. lbs.
% Slip Time of total cycle time = 25%

Sizing Formula
Watts = .0118 x Torque (in. lb.) x Slip RPM x % Slip Time
.0118 x 8 x 500 x .25 = 11.8 watts
Specify: Model SMB-60

Contact Us

Phone
USA: +1-508-987-3206

Email
info@sjogren.com

 

Features within Wire Puller Grips and products

What are wire puller grips? Wire Puller grips are devices that are used to grip and pull wires. They are often used in applications where it is necessary to grip and pull a wire in order to move it. Puller grips are typically made of metal or plastic, and they may be...

read more
Translate »