Torsion Spring Rules & Formulas

Rules and Formulas

                   

Door Weight: (1) Divide the total spring(s) IPPT by the cable drum multiplier

(2) Multiply the spring IPPT by the number of turns, and then divide by the Hi Moment Arm

 

High Lift: Measure the distance from the top of the closed door to the bottom of the horizontal track

IPPT: Inch Pounds Per Turn.  Force spring exerts per 1 turn of the spring

IPPT Required: Multiply the door weight by the Hi Moment Arm, and then divide by the number of turns

 

Spring ID: Measure the outside diameter, and then subtract twice the wire diameter

 

Spring Conversion: Always convert torsion springs to a spring of equal or greater wire diameter

 

Spring Growth-Torsion: Multiply the number of turns by the wire diameter to find spring growth

 

Spring Stretch-Extension: The stretch of an extension spring is always ½ the door height

 

Spring Length: Multiply the wire diameter by the total number of coils in the spring

 

Wire Size: Measure a length of the spring, then divide by the number of coils within that length

About Frank

I am a second generation garage door professional. I have over 35 years of experience in Service, installation, sales, marketing, management and customer service related to the garage door industry. My wife June, brother Clint and son Lucas are also garage door professionals with a combined 60+ years of experience in this industry.