High-cycle torsion spring conversions
A torsion spring is rated in cycles, not years. A door that runs all day on a multi-shift dock burns through a standard rating fast, and a spring failure on a heavy sectional door is a safety event, not just downtime. A high-cycle conversion fits springs matched to the door’s weight and its real cycle count, so the repair stops repeating.
Why does the same door spring keep breaking?
Spring life is set by the spring’s wire size, inside diameter and length relative to the load it carries, and by how it is installed and maintained. The Door & Access Systems Manufacturers’ Association sets these factors out in DASMA Technical Data Sheet 190, Factors Affecting Spring Cycle Life. A door specified for an ordinary duty cycle that ends up running twenty or thirty times a day will use up its rated life in a fraction of the time the building expected.
Source: DASMA Technical Data Sheet #190, Factors Affecting Spring Cycle Life (PDF). Checked 7 September 2026.Replacing a broken spring with the same spring resets the clock but not the rate. A high-cycle conversion changes the spring so the rated life matches how the door is actually used.
Springs are identified against a standard rather than by eye: DASMA Technical Data Sheet 171, Official Color Codes for Torsion and Extension Springs is how a replacement is matched to the original wire size.
Source: DASMA Technical Data Sheet #171, Official Color Codes for Torsion and Extension Springs (PDF). Checked 7 September 2026.What shortens spring life on a working commercial door?
DASMA’s factors sheet reads like a tour of the buildings we service. Wash bays and chlorine-bearing chemicals corrode spring steel toward early failure. Doors left standing open expose the coils to temperature and moisture swings. Rust reduces the wire’s effective area and gives fatigue cracks a starting point. Weight added to the door after manufacture, even paint, can push it past what the counterbalance was specified to carry. And from the installation side, insufficient winding torque shows up as a door that drifts down from its open position over time, which is a symptom worth reporting, not living with. The one habit the sheet endorses for maximizing life: regular lubrication per the door manufacturer’s instructions, which is a standing line item on our maintenance visits.
Source: DASMA Technical Data Sheet #190, Factors Affecting Spring Cycle Life (PDF), Handling, Installation and Door Usage Factors. Checked 7 September 2026.What does a high-cycle spring conversion involve?
We weigh or calculate the door, count or estimate its daily cycles from how the bay operates, and specify springs rated for that load at a high-cycle life. Drums, cables, bearings and the centre bracket are inspected and replaced where worn, because they carry the same cycles the spring does. The door is balanced and the operator force settings re-checked after the conversion.
Which doors actually need high-cycle springs?
- The same door has needed a spring repair more than once in the past year
- The door runs 20 or more times a day, or on more than one shift
- Visible gaps or stretching in the spring coils between failures
- Door has become noticeably harder to open manually
- The bay is one the operation cannot afford to lose for a day
What happens on a spring conversion visit?
- Door weight and cycle countWe measure the door and ask how the bay runs. The spring spec comes from those two numbers.
- Spring and hardware specSprings matched to load at a high-cycle rating, with drums, cables and bearings checked against the same duty.
- Conversion and balanceInstalled, balanced at mid-travel, operator settings re-checked, safety reverse tested.
- LoggedThe new rating goes into the door’s record, so the next inspection knows what it is looking at.
High-cycle spring conversions are available in Hamilton · Stoney Creek · Burlington · Oakville · Milton · Grimsby · St. Catharines · Niagara Region.