Speed, torque & heat calculator
Right Angle Worm Gearbox (90 Deg) Fit Checker
Calculate speed, torque and heat for a 90 degree worm gearbox. Use shaft power and efficiency to prepare your RFQ.
Evidence sources
11
Architecture paths
4
RFQ fields
5
Worm gearbox checker
Enter shaft power, speed and efficiency. Confirm supplier ratings before selecting a model.
Engineering decision guide
Published July 23, 2026 · Reviewed October 21, 2026
Prepared and maintained by AMR Gearbox. Calculations support preliminary sourcing; supplier data controls final selection.
Decision report for right-angle (90 degree) worm gearbox selection
The main goal is not to prove that every 90-degree worm request needs a specific model. The goal is to screen ratio, heat, holding, and architecture fit early enough that the RFQ asks for the right rating evidence.
Key conclusions
Use this table before scanning detailed evidence.
| Decision | Evidence | Action |
|---|---|---|
| 90-degree layout | A 90 degree worm gearbox has perpendicular, offset shafts. The shaft angle does not specify its reduction ratio. Source | Choose the required output speed, then screen torque and losses with the selected unit’s efficiency. |
| Best fit signal | A 90-degree worm stage can be compact and quiet when duty is moderate and holding is not safety-rated. Source | Validate output speed, torque, heat loss, and mounting before sending an RFQ. |
| Escalation signal | Long duty, frequent starts, shock loading, high ratios, or safety holding increase the need for model-specific rating data. Source | Ask for thermal rating, brake strategy, lubricant position, and service factor confirmation. |
| Alternative path | Bevel, hypoid, or multi-stage right-angle designs may suit efficiency-led applications; whole-unit performance varies by product and duty. Source | Compare full-unit efficiency, ratio range, footprint, and power loss before locking the architecture. |
Ratio review prompts
A simple escalation guide for this page, not a product rating.
The ratio prompts only direct users to the next supplier data to request. The checker never infers efficiency or thermal fit from ratio alone; exact product ratings and application conditions control selection.
Ratio and supplier data checklist
Use these prompts to prepare model-specific rating questions.
| Ratio | Efficiency input | Decision use |
|---|---|---|
| 5:1 | Enter vendor efficiency, or use the clearly marked example default. | Screen speed and torque; confirm rated output torque and thermal capacity. |
| 10:1 | Use the selected unit’s efficiency at the relevant load and speed. | Check duty cycle, application factor, and rated output torque. |
| 20:1 | No ratio-only efficiency value is assumed. | Include the supplier thermal rating in the RFQ review. |
| 40:1 | Confirm efficiency and permissible input power for the exact unit. | Confirm thermal capacity at the real duty, ambient, and mounting. |
| 80:1 | This page does not infer efficiency from ratio. | Escalate for supplier rating; this preset is not a fit approval. |
Thermal path
Why the tool reports heat loss instead of torque alone.
The loss estimate is calculated from the entered shaft power and efficiency assumption. It indicates power converted to losses under that assumption; compare duty, ambient, mounting, and the supplier’s thermal rating before selection.
Architecture comparison
Keep worm benefits visible without hiding alternatives.
| Architecture | Advantage | Caution | Use when |
|---|---|---|---|
| Right angle (90 degree) worm gearbox | Compact 90-degree orthogonal package, quiet mesh, and a broad single-stage ratio range (5:1 to 80:1+) in standard product families. | Sliding contact can reduce efficiency, especially at higher ratios. Efficiency, permissible power, and thermal capacity are model- and condition-specific. | A compact 90-degree right-angle layout or a higher single-stage ratio helps the design, and the exact unit passes its rating checks. |
| Right angle bevel gearbox | Can provide high efficiency for suitable ratios; compare complete reducer data, including any helical stages. | A single bevel stage may have a lower ratio range; holding still needs a separately rated brake or lock unless a rated integrated device is selected. | Catalog data confirms an efficiency or thermal advantage for the required ratio, load, and duty. |
| Hypoid right angle gearbox | Some product families provide a compact offset-shaft right-angle layout; complete-unit efficiency depends on the exact design and ratio. | Efficiency, available ratios, lubricant, and cost vary by product family. | Unit-specific data shows a better efficiency/thermal fit for the required offset layout. |
| Planetary plus right-angle stage | A paired planetary and right-angle stage can combine reduction with a compact shaft turn; torque and backlash depend on both units. | More parts, longer stack, and often higher price. | Precision, shock-load capacity, or lifecycle efficiency is a priority and the combined stages meet the package constraints. |
Method and limits
How the checker turns sparse RFQ wording into a defensible engineering screen.
Speed and torque
Output speed is input speed divided by ratio. Torque uses 9550 × shaft input kW ÷ input rpm × ratio × entered efficiency.
Heat loss
Estimated gearbox loss is shaft input power × (1 − entered efficiency); it is not the unit’s thermal capacity.
Holding boundary
Parking preference is informational; safety holding triggers brake or lock review.
Vendor rating
Final selection needs catalog thermal power, shaft loads, mounting, lubricant, and service factor.
The 82% default is an example assumption only. Use the selected gearbox’s efficiency at the relevant load and speed when available. Ratios, duty, shock, and starts create page review prompts; none replaces the manufacturer’s service factor and thermal rating.
Default 5:1 screening trace
Reproducible example using 0.40 kW shaft input, 1500 rpm, 5:1, and the page’s clearly marked 82% efficiency assumption.
| Metric | Screen value | How to use it |
|---|---|---|
| Input case | 0.40 kW shaft input, 1500 rpm, 5:1, 82% assumed efficiency | Illustrative default case; use gearbox shaft power at the operating point and replace the efficiency with vendor data when available. |
| Output speed | 300 rpm | Input speed divided by the 5:1 ratio before downstream reduction. |
| Output torque | 10.4 Nm | Power-derived input torque multiplied by ratio and the entered 82% efficiency assumption. |
| Heat loss | 0.07 kW | Power not delivered to the output shaft; still confirm vendor thermal rating. |
| Application review | Confirm duty and service factor | Starts, shock, duty, and the supplier application factor must be reviewed against the actual load profile. |
Risk and mitigation matrix
Failure modes and the supplier data that resolves each risk.
| Risk | Trigger | Mitigation |
|---|---|---|
| Lubrication starvation in 90-deg mounting | Switching from worm-over to worm-under without adding oil. | Boston Gear notes that some worm-under units need up to 50% more lubricant than worm-over. Verify fill quantity for the exact model and mounting position. |
| Exceeding the unit or lubricant temperature limit | Continuous loss, ambient heat, or mounting pushes the exact product beyond its published limit. | Get the permissible thermal rating and lubricant temperature range for the selected model and operating conditions. |
| Thermal overload | High duty, low efficiency, poor airflow, or small housing. | Ask for thermal power rating at ambient temperature and mounting position. |
| False self-locking assumption | Using worm geometry as a safety brake. | Use a brake or lock designed and rated for the safety function. |
| Lubrication mismatch | Vertical shaft, sealed-for-life unit, or inverted mounting. | Confirm oil level, breather, seal orientation, and service interval. |
| Output shaft overload | Cantilever load, belt pull, wheel load, or shock starts. | Validate radial/axial load and bearing life, not torque alone. |
| Ratio-only RFQ | Spec says only "5:1 right angle worm gearbox". | Add power, speed, duty, mounting, load direction, and environment. |
Backdrive and holding: what ratio cannot tell you
Separate geometry, operating behavior and safety-related holding before choosing a 90 degree worm gearbox.
| Condition | Known | Unknown / limit | Next action |
|---|---|---|---|
| Ratio alone: 5:1 through 80:1 | Ratio gives speed reduction, not lead angle or friction. | Lead angle, worm starts, static and running efficiency: unknown until the exact unit is specified. | Request geometry and backdrive data; never infer a holding function from ratio. |
| Stationary load | Static holding and running backdrive are different conditions. | No universal 4° or 5° cutoff is established for this page. | Have the supplier assess the load, lubricant, temperature and wear state. |
| Vibration, shock or load reversal | Disturbance can change observed self-locking behavior. | A bench observation does not establish vehicle parking or lifting safety. | Design and validate the holding system for actual service conditions. |
| Safety-related holding | SEW prohibits its helical-worm self-locking as the sole safety function for hoists. | Required safety functions and performance levels depend on the application. | Use risk assessment and applicable machine standards to specify and validate a suitable brake or lock. |
Evidence: Swedrive §5.3, SEW product guidance and ISO 13849-1 scope. These sources do not establish a universal ratio-to-lead-angle table or prescribe a particular brake for every machine.
Thermal loss and catalog rating: compare like quantities
Thermal capacity for an enclosed AMR remains unknown until the exact gearbox and cooling conditions are assessed.
| Operating profile | Loss estimate | Rating boundary | Supplier check |
|---|---|---|---|
| Illustrative calculator operating point | 0.40 kW × (1 − 0.82) = 0.072 kW loss. | Permissible input/output power and dissipatable heat are different quantities. | If the catalog specifies permissible input power, compare input power at matching operating conditions. |
| Continuous duty in an enclosure | Calculate losses at the actual shaft operating point. | Ambient, airflow, mounting, lubricant and adjacent heat sources affect the rating. | Request the exact unit’s thermal rating for the enclosure; no universal chassis derating factor is available. |
| Aluminum versus cast iron housing | Material alone does not establish total heat transfer. | Surface area, ribs, contact paths and airflow also matter; model ratings unknown. | Compare complete housings under the same conditions, not material-only kW values. |
| Intermittent duty or added cooling | A transient duty profile needs cycle times, starts and peak load. | No generic duty multiplier or airflow efficiency gain is assumed. | Ask the supplier for an applicable thermal calculation or duty-cycle test. |
A simplified steady-state heat balance is P_loss ≤ K × A × (T_oil − T_ambient), with consistent W units and effective heat-transfer coefficient K. This is an engineering model, not a fitted enclosure rating: K, area, allowable temperatures and other heat paths are not known here. See ISO 14521:2026 scope and SEW’s exact-unit review guidance; no universal derating factor is inferred.
Lubricant selection and conversion checks
Choose an approved product, then verify compatibility and service conditions.
| Oil family | Known | Unknown / limit | Next action |
|---|---|---|---|
| PAG example: Mobil Glygoyle Series | Manufacturer reports lower friction and potential operating-temperature benefits. | No universal efficiency gain, temperature drop or drain interval. | Check OEM approval, exact oil compatibility, seals and coatings before changing oil. |
| PAO-based gear oil | Select an exact approved product and viscosity grade. | Base-oil name alone does not establish mixing, seal suitability or service life. | Request the gearbox lubrication chart and oil supplier’s compatibility guidance. |
| Mineral gear oil | Use only when approved for the gearbox and operating conditions. | No universal friction coefficient or change interval is assumed. | Follow the unit’s service instructions and oil-condition limits. |
Mobil Glygoyle guidance permits some NBR applications within restricted temperature conditions; FKM is not a universal requirement for all PAG oils. Its product-specific mixing, seal and coating checks require OEM review. Conversion can add flushing, seal and downtime costs; retain the approved fill until a change is confirmed.
Applied shaft force versus permissible load
Estimate the load case, then check radial, axial and bending limits for the exact output arrangement.
| Load case | Known / method | Unknown / limit | Next action |
|---|---|---|---|
| Chain, gear or pulley torque transmission | Tangential force F_t = 2000 × M_2 / d_0 (N), with torque in Nm and pitch diameter in mm. | Radial resultant depends on teeth, pressure angle, tension and the chosen catalog factor. | Use the selected supplier’s method; compare the applied force with its permissible radial load. |
| Illustrative sprocket calculation | 10 Nm at 100 mm gives F_t = 200 N before additional loads. | This is an applied tangential force, not a permissible shaft rating. | Add applicable transmission factors and preload; record the load direction and application point. |
| Direct wheel hub on a gearbox shaft | Include vehicle weight, traction, impacts, cornering and wheel offset. | Torque divided by wheel radius does not describe all bearing loads. | Provide a combined radial/axial load and bending-moment case to the gearbox supplier. |
| Offset force or combined axial load | Permissible load depends on shaft geometry, bearing life, speed and load location. | No universal midpoint correction or shock multiplier is provided here. | Use the exact catalog’s load-position correction and combined-load limits. |
Evidence: SEW overhung-load guidance. Its element factors vary with tooth count and preload. Do not apply one catalog’s factors or permissible loads to another gearbox; provide load direction, distance from the shoulder and simultaneous axial load for supplier review.
RFQ packet
Minimum fields to turn a 5:1 right-angle worm request into a supplier-ready inquiry.
| Field | Why it matters | Example |
|---|---|---|
| Power and speed | Converts the ratio request into input torque, output speed, and heat loss. | 0.40 kW gearbox shaft input, 1500 rpm, 5:1 reduction. |
| Duty profile | Separates intermittent indexing from thermal continuous duty. | 8 hours/day, 20 starts/hour, moderate shock. |
| Mounting and shaft layout | Controls lubrication, seal life, and package fit. | Hollow output, foot mounted, horizontal worm shaft. |
| Holding requirement | Prevents using worm backdrive behavior as an unverified safety brake. | Parking hold only; external brake if safety-rated. |
| Environment | Ambient heat, washdown, dust, and vibration change derating. | 35 C ambient, indoor conveyor, IP54 target. |
Use-case examples
Hypothetical profiles for mapping application language to a decision path; they are not ratings for specific products.
| Scenario | Input profile | Likely path |
|---|---|---|
| Light conveyor turn station | 0.25 to 0.55 kW, 5:1 to 10:1, 8 h/day. | Catalog screen plus mounting and radial-load check. |
| AMR accessory lift or latch | Low speed, intermittent duty, parking hold preference. | Worm may fit, but safety holding needs separate design. |
| Continuous mixer or auger | High duty, heavy shock, warm ambient. | Thermal rating and service factor gate before selection. |
| Battery vehicle drive axis | Runtime-sensitive with frequent starts. | Compare bevel or hypoid efficiency before choosing worm. |
Evidence sources
Traceable inputs used to shape the calculator limits and RFQ guidance.
| Source | Use in this page |
|---|---|
| Lubrication and mounting orientationsBoston Gear | Product-specific oil-fill guidance; not a universal fill rule. |
| ANSI/AGMA 6034-C21 — public scopeAGMA | Cylindrical wormgear rating scope, including thermal capacity and lubrication. Worm speed scope is up to 3600 rpm; full clauses are not reproduced or verified here. |
| ISO 14521:2026 — public abstractISO | September 2026 edition replaces ISO/TS 14521:2020. Covers cylindrical wormgear load capacity including temperature, with geometry/speed applicability limits; not a universal enclosure derating rule. |
| Worm gears — operating instructions, §5.3Swedrive | Pitch-angle and friction dependencies; worm gearing alone is not a safety device. |
| Self-locking — product guidanceSEW-Eurodrive | Helical-worm context: self-locking is not permitted as the sole safety function for hoists. Do not transfer a product threshold to every worm gearbox. |
| ISO 13849-1:2023 — public abstractISO | Safety-related control-system design methodology; it does not prescribe application-specific safety functions, required performance levels or a particular brake type. |
| Mobil Glygoyle Series — product data, March 2025ExxonMobil | Product-specific PAG compatibility and oil-conversion guidance; no universal efficiency gain or maintenance interval. |
| Determining the overhung load — DRN.., February 2026SEW-Eurodrive | Applied-force method and transmission factors depend on element geometry and preload; permissible shaft loads require catalog data. |
| Thermal rating — X..e product guidanceSEW-Eurodrive | Exact-unit thermal review principle, in helical/bevel-helical context; not wormgear numerical rating data. |
| Efficiency — general informationSEW-Eurodrive | Starting versus running efficiency, especially for helical-worm and SPIROPLAN drives; no universal breakaway multiplier. |
| Angled gear units — bevel or worm, November 2024NORD Drivesystems | Architecture and sliding-contact tradeoffs; whole-unit performance depends on the operating point. |
Internal resources
Compare related drive architectures and selection guides.
80:1 right angle worm gearbox calculator
Estimate speed, running torque and heat at 80:1 with explicit efficiency assumptions and downloadable results.
worm gearbox ratio and thermal checker
Use when the question is worm gearbox first and does not require a right-angle-specific decision path.
90 degree bevel gearbox comparison
Use when high efficiency or true 90-degree transfer is more important than worm reduction.
right angle gearbox product families
Use after an initial architecture comparison; confirm the exact model’s ratings with the supplier.
worm gearbox product family
Use when the right-angle requirement still needs broader worm gearbox product options.
gearbox efficiency comparison resource
Use when heat loss or battery life may outweigh the compact worm layout.
Frequently asked questions
Practical answers for 90 degree worm gearbox, 5:1 presets, and adjacent right-angle sizing questions.
Is a 90 degree worm gearbox the same as a right angle worm gearbox?
Yes. "90 degree worm gearbox" and "right angle worm gearbox" describe the identical mechanical configuration where input and output shafts are oriented at a 90-degree perpendicular angle. Engineers often use the terms interchangeably when specifying compact orthogonal drivetrains for conveyors, AGVs, and industrial machinery.
Why is it called a 90 degree worm gearbox?
Because the worm screw and worm wheel are mounted on non-intersecting, perpendicular axes, creating an exact 90-degree right angle between the motor input and the driven load. This compact 90-degree turn is one of the main reasons designers choose a worm drive over in-line planetary or parallel shaft helical gearboxes.
How efficient is a 90 degree worm gearbox compared to other right-angle drives?
There is no single efficiency value for the whole 90-degree worm category. It depends on the exact gear geometry, ratio, load, speed, lubricant, and operating condition. NORD notes that higher-ratio worm stages (about i > 10) are less efficient than bevel stages due to sliding tooth friction, but that does not establish the efficiency of a particular 5:1 unit. Use the selected unit’s catalog value at the relevant operating point, then compare complete drive trains.
Does a 90-degree orientation affect lubrication?
It can. Boston Gear reports that some units in worm-under orientation require up to 50% more lubricant than worm-over units. That is product-specific guidance, not a universal fill rule. Include the exact mounting position in your RFQ and follow the selected manufacturer’s fill chart.
What is the maximum operating temperature for a worm gearbox?
There is no universal temperature limit for every worm gearbox or lubricant. Check the selected unit’s thermal rating, permitted oil temperature, lubricant specification, ambient conditions, duty, and mounting position. AGMA 6034-C21 covers thermal capacity and lubrication for its defined cylindrical wormgear scope; final rating requires product and application data.
What lead angle is required for self-locking in a 90 degree worm gearbox?
No single lead angle or ratio guarantees self-locking across worm gearboxes. Geometry, friction, lubricant, wear and disturbance affect static and dynamic behavior. Request exact-unit backdrive data and a validated holding design for slopes or lifts. Swedrive and SEW explain the limitations; the calculator does not assess self-locking.Evidence and scope
Can I use synthetic PAG oil in any 90-degree worm gearbox?
No. Obtain OEM approval for the exact oil, viscosity, seals and coatings before a conversion. Mobil Glygoyle guidance says FKM and VMQ are normally suitable; some NBR use is possible within restricted temperatures. Mixing and flushing instructions depend on the products. No fixed efficiency gain or drain interval is promised.Evidence and scope
What is the difference between mechanical rating and thermal rating?
Mechanical ratings address component load capacity. A thermal rating limits operation under stated ambient, duty, mounting and cooling conditions. Check whether the catalog rates permissible input power, output power or dissipatable heat before comparing quantities. This page estimates loss, not thermal capacity, and supplies no universal enclosure derating factor.Evidence and scope
Why does my motor struggle to start a high-ratio worm gearbox under load?
Starting efficiency can be lower than running efficiency, especially in sliding-contact drives. Use supplier starting-torque or starting-efficiency data at the actual temperature and load, and check the motor/controller peak torque. This steady-state calculator does not estimate breakaway torque or a universal starting multiplier.Evidence and scope
How do I calculate permissible radial load on the output shaft for chain or belt drives?
First calculate tangential force F_t = 2000 × M_2 / d_0, using Nm and mm to obtain N. This estimates applied force, not permissible radial load. Use the selected catalog’s element factors, preload, load position and combined radial/axial limits to check the shaft.Evidence and scope
What does 5:1 right angle worm gearbox mean?
The input turns five times per output revolution. At 1500 rpm input, output speed is 300 rpm before downstream reduction. Torque and heat still depend on shaft power and the exact unit’s efficiency.
Does the 90-degree shaft angle specify the ratio?
No. The shaft angle describes the layout; the reduction ratio describes the speed change. Choose the ratio from the required output speed and check the exact unit’s ratings.
When is a 5:1 right-angle worm gearbox a good fit?
It may suit a compact 90-degree layout, moderate reduction, quiet operation, and a simple package. Compare other architectures when efficiency, heat, or safety-rated holding is the dominant constraint.
How do I estimate output speed for a 5:1 unit?
Divide input speed by five. A 1500 rpm motor gives about 300 rpm output before any downstream chain, belt, or wheel reduction.
How does the checker estimate output torque?
It converts entered gearbox shaft input power and speed into input torque, multiplies by the ratio and the efficiency assumption you enter. The default 82% is only an example; replace it with the selected unit’s data when available. The result is an RFQ screen, not a vendor rating.
Can I rely on the worm gearbox for self-locking?
Do not treat worm self-locking as a safety function. Lead angle, lubrication, wear, vibration, and shock can change backdriving behavior, so safety-rated holding needs a rated brake or lock.
Why does thermal loss matter on a worm gearbox?
The power not delivered to the output becomes heat. As ratio, load, ambient temperature, and duty increase, thermal rating can become the selection limit before mechanical torque does.
When should I compare bevel, hypoid, or planetary right-angle drives?
Compare alternatives when runtime, continuous duty, precise backlash, high shock load, or safety holding is central to the machine. Worm gearboxes are compact and quiet, but not always the efficient choice.
Does mounting position change the answer?
Yes. Mounting controls oil level, breather position, seal exposure, bearing loads, and heat path. Include mounting orientation before asking for a final model.
What should I do if the tool returns an engineering boundary?
Send the RFQ packet fields from this page and ask for thermal rating, service factor, brake strategy, and lubrication confirmation. A boundary is a page-level escalation prompt, not a product rejection or approval.
Can the checker be used on mobile?
Yes. The inputs use touch-friendly controls and the result panel keeps the main answer, evidence, and next actions visible without requiring a desktop table.
Is this page final sizing advice?
No. It is an early engineering screen that improves RFQ quality. Final selection still requires supplier data for rated torque, thermal power, shaft loads, lubrication, backlash, and environment.
Ready to convert the screen into an RFQ?
Send the ratio, motor power, input speed, duty profile, mounting position, shaft load, environment, and holding requirement. Mention any boundary result from the checker.