Use this single page to run a practical 0.5 hp worm gearbox fit check, then validate method, boundaries, and risks before RFQ. This intentionally maps queries "worm gearbox", "0.5 hp worm gearbox", "1 4hp worm gearbox", "1 1 worm gearbox", and "00611e worm gearbox slide out" to one canonical URL while separating alias wording from true 1:1 mechanical-ratio decisions.
Power reference for this checker: 0.5 hp is treated as about 0.373 kW by NIST conversion and 1/4 hp as about 0.186 kW, with explicit boundary-state behavior if exceeded.
Canonical internal link: 1 4hp worm gearbox · 1 1 worm gearbox · 0.5 hp worm gearbox · Fast jump: run tool · key conclusions · 1:1 decision gate · 1 1 worm gearbox answer · 0.5 hp worm gearbox answer · 1 4hp worm gearbox answer · 00611e worm gearbox slide out answer
Published: April 28, 2026 · Last updated: April 29, 2026
Evidence pack: 19 cited sources (ANSI/AGMA, ISO, SEW, NORD, EIA, OSHA) · Last verification: 2026-04-29
Shock level
S2/S3 evidence boundary: worm-stage efficiency is ratio/speed/temperature sensitive and can be materially lower during run-in.
Mid-layer summary for fast decisions: what is likely to work, where limits begin, and who should not use a 0.5 hp worm gearbox path without additional validation.
Preferred when required reduction ratio stays within 8:1-80:1 in this quick-screen heuristic.
Current estimate: 20.0:1
Use service factor 1.55 based on shock and duty, then size rated torque above 85.4 Nm.
Keep computed input power near 0.5 hp scope marker (0.373 kW) for this page intent; otherwise treat as boundary and escalate.
Estimated loss is 0.11 kW. This is the main risk in sealed or compact enclosures.
S3 run-in evidence: early operation can show lower efficiency for roughly 48 hours, so do not freeze procurement on cold start assumptions.
This stage separates alias wording from true mechanical 1:1 architecture. It prevents teams from forcing worm reducers into no-reduction cases without explicit efficiency and safety justification.
| Checkpoint | What published sources show | Decision implication | Refs |
|---|---|---|---|
| Worm-stage practical ratio envelope | NORD guidance summarizes single worm-stage practice at roughly i = 4 to 100. | A strict 1:1 requirement is outside common worm-stage sizing patterns and should not be assumed viable by default. | S16, S19 |
| True 1:1 right-angle transmission baseline | NORD bevel guidance lists usual per-stage ratios of 1:1 to 1:10 with about 96%-98% efficiency. | If no reduction is required, use bevel/direct baselines first, then prove why worm remains preferable. | S17 |
| Self-locking expectation | NORD and SEW both describe self-locking as conditional behavior, not a universal guarantee. | Do not use self-locking as your only safety control; design independent hold/brake verification. | S4, S16, S17 |
| Published worm-family ratio minimums | SEW S-series lists i = 3.97-288 and Bonfiglioli tables repeatedly show 7 <= i <= 100 ranges. | Keep alias-intent coverage on one URL, but treat mechanical 1:1 requests as an explicit architecture exception workflow. | S6, S19 |
Assumption set: required mechanical output 0.25 kW, worm at 70% vs bevel at 97%, running 6,000 h/year.
| Input power (worm) | 0.357 kW |
| Input power (bevel baseline) | 0.258 kW |
| Extra input power if worm is kept | 0.099 kW |
| Annual extra electricity | 596.5 kWh/year |
| Annual extra cost (EIA industrial 2025 average) | $51.4/year |
| Annual extra cost (EIA Jan-Feb 2026 range) | $53.4-55.4/year |
Pricing references come from EIA Electric Power Monthly Table 5.3 (released on 2026-04-23). Vendor-specific efficiency curves can move this estimate materially.
If result is Fit or Conditional, send your torque/speed/duty inputs with thermal and backlash requirements to the supplier RFQ packet.
Jump to the canonical alias answer when RFQ notes use 1 4hp wording for a 1/4 hp request.
Jump to the canonical alias answer when stakeholders use 1 1 wording in RFQ discussions.
Use this section when teams need to separate alias wording from a real mechanical 1:1 requirement.
Jump directly to alias-intent handling and slide-out boundary checks.
Use this related page when right-angle efficiency trade-offs favor bevel architecture.
Use this related page when motor-speed constraints dominate gearbox shortlist decisions.
Share duty cycle and constraints to start supplier screening.
Review architecture and implementation details before rollout.
Read supporting engineering context and trade-off breakdowns.
Share scope, timeline, and quantity targets for quotation planning.
Verify expertise, operating model, and support coverage.
Deep layer: calculation logic, source scope, and known uncertainty so decisions are auditable.
| Step | Formula / Rule | Output |
|---|---|---|
| Output torque | Input torque × reduction ratio × efficiency | Primary torque estimate |
| Service factor | Shock factor × duty factor | Load amplification |
| Recommended rating | Required torque × service factor | Minimum gearbox rating |
| Thermal loss | Input power × (1 - efficiency) | Heat burden for enclosure |
| Grade | Ratio + thermal + margin gates (heuristic screen) | Fit / Conditional / Not Fit |
| Current gate values | Conditional: ratio <8:1 or >80:1 OR thermal >0.25 kW OR margin<12% Not fit: ratio <5:1 or >120:1 OR thermal >0.45 kW Boundary-state: computed input power >0.393 kW for 0.5 hp scope | Fast-screen only; replace with supplier validation for final design. |
| Boundary | Value | How to use it | Source |
|---|---|---|---|
| 0.5 hp power marker | 0.373 kW | Keep tool intent aligned with "0.5 hp worm gearbox"; above boundary means directional-only output. | S10 |
| AGMA worm-speed scope | <= 3600 rpm | Treat higher-speed assumptions as out-of-scope for direct AGMA 6034 quick mapping. | S1 |
| AGMA sliding-velocity scope | <= 6000 ft/min | Require explicit worm-specific validation when sliding velocity assumptions exceed this range. | S1 |
| SEW run-in window | Typically 48 h | Avoid using early cold-start efficiency as steady-state acceptance data. | S3 |
| SEW run-in efficiency reduction | ~2% to 12% (ratio dependent) | Use conservative thermal margin before declaring "fit" in the first operation window. | S3 |
| NORD practical worm-stage ratio | Approx. i = 4 to 100 | Use as boundary context when clarifying if "1 1" is alias wording or an actual mechanical 1:1 requirement. | S16 |
| NORD bevel-stage baseline | 1:1 to 1:10, ~96% to 98% | If no reduction is required, compare worm decisions against this baseline before RFQ lock. | S17 |
| EIA industrial electricity markers | 2025 annual 8.62 cents/kWh; Jan 2026 9.29; Feb 2026 8.95 | Use for first-pass OPEX sensitivity only; replace with site contract tariff in final TCO. | S18 |
| OSHA hearing action level | 85 dBA, 8-h TWA | Add monitoring/hearing-conservation controls even if torque and thermal checks pass. | S8 |
| Fact | Boundary / Counterexample | Sources | Updated |
|---|---|---|---|
| ANSI/AGMA 6034-C21 explicitly constrains rating scope to worm speeds <= 3600 rpm and mesh sliding velocity <= 6000 ft/min. | If proposal assumptions exceed this scope or omit worm-specific variables (thermal/service/lubrication), quick-fit confidence should be reduced. | 2026-04-28 | |
| SEW project-planning guidance states helical-worm efficiency depends on ratio, input speed, and ambient temperature, and can drop below eta = 0.5 at very high ratios. | Do not reuse a single catalog efficiency number across different duty temperatures and ratio classes. | 2026-04-28 | |
| Run-in behavior is materially non-trivial: published helical-worm run-in corrections are approximately 2% to 12% efficiency loss, and the run-in phase usually lasts 48 hours. | Ignoring run-in can overstate early-stage output torque and understate initial thermal load. | 2026-04-28 | |
| Self-locking is conditional: SEW notes static self-locking when forward efficiency is eta <= 0.5 and explicitly forbids using this effect as the sole safety function for hoists. | Treat self-locking as a characteristic, not as a replacement for independent braking and hold verification. | 2026-04-28 | |
| R/F/K family references can reach up to 96% (3-stage), 97% (2-stage), and 98% (1-stage), while K two-stage references include over 90% designs. | Higher-efficiency alternatives can reduce thermal burden, but they may increase architecture complexity and still require backdrive/safety review. | 2026-04-28 | |
| Current S-series public envelope includes ratio 3.97-288, power 0.12-30 kW via motor adapter, and max listed output torque up to 4300 Nm. | A 0.5 hp project is a small subset within this broad envelope and must still be validated against frame-specific data. | 2026-04-28 | |
| NIST conversion factors give 1 hp = 745.6999 W, so 0.5 hp ~= 0.373 kW, which this tool now uses as a scope boundary check. | If computed input power exceeds 0.5 hp nominal by more than the tolerance band, keep result as directional and escalate to supplier sizing. | 2026-04-28 | |
| OSHA 1910.95 sets a hearing-conservation action level at 85 dBA (8-hour TWA) and Table G-16 shows 90 dBA at 8 hours as a permissible-noise reference point. | A torque/thermal fit does not imply acoustic compliance; machine-level noise measurements remain mandatory. | 2026-04-28 | |
| NIOSH keeps REL at 85 dBA (8-hour average) and applies a 3 dBA exchange rate (every +3 dBA halves allowable exposure time). | Plants using conservative health targets should not rely solely on OSHA minimum compliance thresholds. | 2026-04-28 | |
| HSE (updated 2025-03-06) summarizes 80/85/87 dB(A) thresholds aligned with EU-derived workplace-noise controls. | Cross-region deployments should align the stricter threshold set used by each site before procurement lock. | 2026-04-28 | |
| SEW run-in guidance states nominal efficiency is valid only after run-in completion, nominal operating temperature, recommended lubricant fill, and nominal load range; if used in both rotation directions, each direction has its own run-in phase. | Do not freeze acceptance based on first-shift cold commissioning data; include run-in and hot-state checkpoints in FAT/SAT. | 2026-04-28 | |
| SEW DRC design notes show mounting position changes require lubricant quantity adaptation and may require consultation with SEW-EURODRIVE before startup. | For slide-out retrofit or remounting, re-validate mounting-position oil quantity before return-to-service. | 2026-04-28 | |
| SEW disassembly notes for shaft-mounted units specify a controlled removal sequence using forcing washer/fixed nut hardware from the installation/removal kit. | Treat ad-hoc pry-force extraction as a damage-risk path; require documented removal tooling and sequence. | 2026-04-28 | |
| OSHA 1910.147 requires an energy-control program before servicing/maintenance where unexpected startup or stored energy release could cause injury, and includes periodic inspection obligations. | Slide-out/disassembly tasks should be blocked from execution without LOTO isolation and stored-energy verification. | 2026-04-28 | |
| OSHA 1910.212 requires guarding against point-of-operation, ingoing nip-point, and rotating-part hazards when machines are in operation. | After gearbox reinstallation, commissioning should include guard restoration verification before power-on testing. | 2026-04-28 | |
| ISO 14118:2017 applies unexpected-startup prevention to electrical, hydraulic, pneumatic, stored, and external energy, but does not prescribe machine-specific means or SIL/PL targets. | Do not assume a generic standard clause closes design risk; machine-level controls must be specified by risk assessment and product-specific standards. | 2026-04-28 | |
| NORD engineering guidance states a single worm stage typically operates in about i = 4 to 100 in practice and can become less efficient than bevel alternatives at larger ratios. | If your requirement is true 1:1 transfer, treat worm architecture as an exception case that needs explicit justification instead of default selection. | 2026-04-29 | |
| NORD bevel-stage guidance lists usual per-stage ratios of 1:1 to 1:10 with about 96% to 98% efficiency and states bevel stages are not self-locking. | For real 1:1 right-angle tasks, bevel/direct architectures are often a better efficiency baseline, but hold/brake functions must be designed separately. | 2026-04-29 | |
| SEW S-series product data gives ratio range i = 3.97 to 288 and reports up to +13 percentage-point efficiency uplift for S..7p combinations at large ratios. | Even with improved helical-worm combinations, published worm-family ranges still start well above 1:1, so alias wording must not be interpreted as automatic mechanical 1:1 fit. | 2026-04-29 | |
| EIA Table 5.3 reports U.S. industrial average electricity prices of 8.62 cents/kWh for annual 2025, 9.29 cents/kWh in January 2026, and 8.95 cents/kWh in February 2026. | Where energy cost matters, even small efficiency deltas in near-1:1 architecture can create measurable OPEX differences and should be included in TCO checks. | 2026-04-29 | |
| Bonfiglioli VF-W catalog tables repeatedly list worm ratio bands such as 7 <= i <= 100 and discrete ratio sets (for example 7, 10, 14 ... 100) across multiple frames. | Do not assume catalog availability for a mechanical 1:1 worm stage; require frame-level confirmation before quote comparison. | 2026-04-29 |
| ID | Source | Published | Usage In Page | Confidence |
|---|---|---|---|---|
| S1 | ANSI/AGMA 6034-C21 Practice for Enclosed Cylindrical Wormgear Speed Reducers and Gearmotors AGMA / MPMA | ANSI approval date: 2021-04-09 Verified 2026-04-28 | Provides worm-reducer rating scope (speed/sliding-velocity limits) and confirms thermal capacity, service factor, lubrication, and self-locking are explicit parts of the method. | High |
| S2 | SEW-EURODRIVE project planning: S and W gear units efficiency behavior SEW-EURODRIVE | Edition 11/2025 Verified 2026-04-28 | Documents that worm-stage efficiency is ratio/speed/temperature dependent and can drop below 0.5 at very high ratios. | High |
| S3 | SEW-EURODRIVE project planning: run-in phase for helical-worm stages SEW-EURODRIVE | Edition 11/2025 Verified 2026-04-28 | Defines run-in effects, including typical 48-hour duration and ratio-dependent efficiency reduction (around 2% to 12% in published tables). | High |
| S4 | SEW-EURODRIVE project planning: self-locking note SEW-EURODRIVE | Edition 11/2025 Verified 2026-04-28 | Defines static self-locking condition at forward efficiency <= 0.5 and states it must not be the sole safety function for hoists. | High |
| S5 | SEW-EURODRIVE project planning: R/F/K gear-unit efficiency reference SEW-EURODRIVE | Edition 11/2025 Verified 2026-04-28 | Provides right-angle alternative efficiency context: up to 96% (3-stage), 97% (2-stage), and 98% (1-stage) for R/F/K families. | Medium |
| S6 | SEW-EURODRIVE S-series helical-worm gear units product page SEW-EURODRIVE | Product page (current) Verified 2026-04-28 | Provides publicly listed operating envelopes: ratio 3.97-288, motor-adapter power 0.12-30 kW, torque up to 4300 Nm, and S..7p efficiency uplift claims. | Medium |
| S7 | ISO 6336-1:2019 Calculation of load capacity of spur and helical gears ISO | 2019-11 (confirmed current in 2025) Verified 2026-04-28 | Sets a scope boundary: this series is for spur/helical cylindrical gears and explicitly states limits and non-applicable failure conditions. | High |
| S8 | OSHA 29 CFR 1910.95 Occupational noise exposure OSHA / eCFR | Regulation page (ongoing updates) Verified 2026-04-28 | Defines U.S. action and control thresholds used in factory risk reviews: 85 dBA hearing-conservation trigger and Table G-16 90 dBA at 8 h. | High |
| S9 | CDC/NIOSH Noise-Induced Hearing Loss (REL overview) CDC / NIOSH | Page date: 2024-01-30 Verified 2026-04-28 | Provides 85 dBA REL and the 3 dBA exchange-rate rule used for conservative noise-exposure planning. | High |
| S10 | NIST Guide to SI Appendix B.9 (horsepower-to-watt conversion factors) NIST | NIST SP 811 Appendix B.9 (online current) Verified 2026-04-28 | Provides the unit anchor for this page scope check: 1 hp = 745.6999 W, so 0.5 hp ~= 0.373 kW. | High |
| S11 | HSE Control of Noise at Work Regulations summary UK HSE | Updated 2025-03-06 Verified 2026-04-28 | Adds EU-derived operational thresholds (80/85/87 dB(A)) to cross-check multinational plant rollouts. | High |
| S12 | OSHA 29 CFR 1910.147 The control of hazardous energy (lockout/tagout) OSHA / eCFR | Regulation page (first published 1989; ongoing updates) Verified 2026-04-28 | Defines maintenance safety controls for unexpected energization/startup and stored energy release during servicing/disassembly, including periodic inspection of energy-control procedures. | High |
| S13 | OSHA 29 CFR 1910.212 General requirements for all machines OSHA / eCFR | Regulation page (ongoing updates) Verified 2026-04-28 | Requires guarding against hazards from point-of-operation, ingoing nip points, and rotating parts when machine power is restored after maintenance. | High |
| S14 | ISO 14118:2017 Safety of machinery — Prevention of unexpected start-up ISO | Published 2017-12; confirmed current 2023-03-27 Verified 2026-04-28 | Covers unexpected start-up prevention for electrical/hydraulic/pneumatic/stored/external energy and clarifies machine-specific means must be set by risk assessment or type-C standards. | High |
| S15 | SEW-EURODRIVE DRC Gearmotors catalog: design and operating notes SEW-EURODRIVE | Catalog document 19377215_G06 (indexed 2025-11) Verified 2026-04-28 | Provides installation/removal kit details, tightening torques, hollow-shaft disassembly process, reduced-backlash availability limits, and lubrication/mounting-position dependencies. | High |
| S16 | NORD blog: Design and application of angled gear units NORD DRIVESYSTEMS | Published 2024-11-05 Verified 2026-04-29 | Documents practical worm-stage ratio envelope (about i = 4 to 100), efficiency sensitivity at high ratios, and conditional self-locking behavior only for certain toothings under reverse power flow. | Medium |
| S17 | NORD blog: Design and application of bevel gear units NORD DRIVESYSTEMS | Published 2024-10-15 Verified 2026-04-29 | Provides right-angle baseline for true 1:1 discussions: per-stage ratios usually 1:1 to 1:10, efficiency around 96% to 98%, and no inherent self-locking. | Medium |
| S18 | EIA Electric Power Monthly Table 5.3 (Retail sales and revenue) U.S. Energy Information Administration (EIA) | Released 2026-04-23 (includes data through 2026-02) Verified 2026-04-29 | Supplies U.S. industrial electricity price markers used for operating-cost sensitivity in this page (annual 2025 and Jan/Feb 2026 values). | High |
| S19 | Bonfiglioli VF-W catalog ratio distribution tables Bonfiglioli Catalog table extraction can vary by OCR parser; confirm exact frame-specific rows during RFQ. | Catalog revision R11_5_1 (current public PDF) Verified 2026-04-29 | Shows worm-family ratio distributions in discrete sets and repeated 7 <= i <= 100 ranges across multiple frame combinations. | Medium |
| Topic | Status | Decision Impact | Minimum Executable Path |
|---|---|---|---|
| Cross-vendor hot-state efficiency dataset for 0.5 hp worm gearbox models under one measurement protocol | No reliable open normalized dataset found (as of 2026-04-29). | Selecting by catalog peak values can overstate real continuous-duty performance. | Request model-level efficiency curve by speed and temperature for each shortlisted vendor. |
| Cross-vendor backdrive and self-locking behavior under wear/lubrication drift | No reproducible open dataset found (as of 2026-04-29). | Teams may overestimate hold performance and under-design independent braking safeguards. | Treat self-locking as conditional and include independent hold-brake verification in FMEA. |
| Comparable thermal derating curves across brands at identical enclosure conditions | Partial vendor data only; no harmonized public benchmark. | Direct efficiency comparison cannot replace thermal validation under actual mounting and cooling. | Request continuous thermal rating curve and mounting-position correction from each shortlisted supplier. |
| Cross-vendor gearbox-noise benchmarks measured with identical load and mounting conditions | No harmonized open benchmark found (as of 2026-04-29). | A design can pass torque and thermal checks while still creating non-compliant occupational noise in one plant layout. | Add site-level noise measurements to FAT/SAT and align OSHA or local threshold policy before final acceptance. |
| Public model-code mapping for "00611e worm gearbox slide out" to a verified OEM gearbox family | Targeted searches on OEM domains (SEW/NORD) found no reliable public model mapping as of 2026-04-29. | Applying generic removal assumptions to an unknown code string can cause tooling mismatch and service delays. | Require nameplate photos, serial/model traceability, and OEM manual confirmation before creating field slide-out steps. |
| Cross-vendor measured efficiency dataset for true 1:1 right-angle transmission duty | No harmonized open dataset found (as of 2026-04-29); vendor publications focus on different frame classes and test methods. | Teams can over-generalize one catalog curve and mis-estimate energy cost when deciding between worm and bevel at near-1:1 requirements. | Request same-test-method efficiency curves and measurement conditions from each shortlisted vendor before final architecture lock. |
| Option | Evidence-backed efficiency view | When it works well | Counterexample / limit | Source refs |
|---|---|---|---|---|
| Worm / helical-worm path (target) | Ratio/speed/temperature dependent; published guidance notes efficiency can drop below eta = 0.5 at very high ratios. | Right-angle reduction where compactness and cost priority justify thermal-management effort. | Run-in and hot-state behavior can invalidate optimistic cold-start assumptions for 0.5 hp projects. | S1, S2, S3 |
| True 1:1 right-angle transfer requirement | NORD bevel-stage guidance states usual 1:1-1:10 range with about 96%-98% efficiency, while practical worm stage guidance starts around i = 4. | Cases where output speed should stay close to motor speed and TCO sensitivity is high. | Treating alias wording as automatic worm-fit can lock in avoidable thermal and energy penalties. | S16, S17, S18, S19 |
| Helical or helical-bevel alternative | R/F/K references include up to 96%/97%/98% in corresponding stage classes; K two-stage references include over 90%. | Cases where thermal budget is tight and long-duty energy loss dominates lifecycle cost. | Replacing worm path without checking hold/backdrive behavior can break functional safety expectations. | S4, S5 |
| Method / standards traceability path | Keep worm-reducer rating and scope boundaries explicit in RFQ, instead of mixing formula families. | Teams that need auditable procurement and acceptance criteria. | Using spur/helical-only logic as final proof for worm reducers can misstate risk. | S1, S7 |
| Slide-out maintenance readiness (alias intent) | OEM notes define controlled installation/removal kit steps plus mounting-position/lubricant dependencies. | Teams planning field disassembly/replacement with a known model identity and documented service method. | If model code mapping is unclear (for example, raw query token "00611e"), generic pull-out steps can become unsafe or inapplicable. | S12, S14, S15 |
| Cross-vendor precision/backlash benchmark | N/A: no reliable open normalized dataset found. | Decision can proceed only after supplier test-method alignment. | Treating marketing backlash numbers as directly comparable across vendors is high risk. | Open gap (see method section) |
| Occupational noise compliance gate | OSHA 85 dBA action level, NIOSH REL 85 dBA with 3 dBA exchange, and HSE 80/85/87 dB(A) thresholds all require explicit site policy alignment. | Plants with strict health-policy posture or EU/UK obligations. | A torque-pass design can still fail acoustic acceptance at installation. | S8, S9, S11 |
Typical decision failure is not ratio itself but missing evidence in thermal, backlash, and duty-cycle validation.
| Risk Type | Impact | Probability | Trigger / Boundary | Mitigation | Refs |
|---|---|---|---|---|---|
| Underestimated shock load | High | Medium | Service factor not aligned with actual duty-cycle and shock profile. | Raise service factor and validate duty profile with real cycle data. | S1, S2 |
| Thermal saturation in sealed housing | High | Medium-high | Thermal loss exceeds enclosure cooling capacity under continuous duty. | Check continuous thermal rating and enclosure cooling budget. | S1, S2, S3 |
| Alias wording misread as true 1:1 fit | Medium-high | Medium | Team reads "1 1 worm gearbox" or "1 4hp worm gearbox" as mandatory mechanical 1:1 while the selected architecture still assumes worm-stage reduction behavior. | Run the 1:1 boundary table, compare bevel baseline, and document why worm remains selected if no reduction is required. | S16, S17, S18, S19 |
| Backlash mismatch with precision tasks | Medium-high | Medium | Supplier backlash class and test method absent in quote package. | Specify backlash class and acceptance test in RFQ. | Open gap |
| Lubrication interval mismatch | Medium | High | Lubrication schedule not linked to temperature/load profile. | Define lubricant grade, interval, and field service trigger. | Open gap |
| Self-locking assumed as sole safety mechanism | High | Low-medium | Using worm-stage self-locking assumption without dedicated braking function. | Add independent safety brake and verify static/dynamic hold strategy. | S4 |
| Method mismatch between gearbox families | Medium-high | Low | Quotes compare worm paths with spur/helical-only methods and omit scope boundaries. | Require explicit method statement and scope fit before design freeze. | S1, S7 |
| Slide-out maintenance without LOTO isolation | High | Low-medium | Servicing/disassembly starts before isolating hazardous energy and checking stored energy release risk. | Enforce energy-control procedure, isolation point list, and periodic inspection before field slide-out work. | S12, S14 |
| Re-commissioning without guard restoration | High | Low | Gearbox/motor rotation and nip-point guards are not restored after reassembly. | Add pre-power-on guard checklist and acceptance sign-off in SAT workflow. | S13 |
| Noise compliance mismatch | Medium-high | Medium | No site-level measurement against 85 dBA action criteria (or stricter local threshold set). | Add FAT/SAT measurement plan and apply the stricter of local policy, OSHA, and corporate health rules. | S8, S9, S11 |
Assumption: Input 4 Nm @ 900 rpm (~0.38 kW), moderate shock, 16 h/day.
Process: Checker estimates service factor and recommended rated torque for a 0.5 hp worm gearbox path with thermal loss projection.
Outcome: Recommended rated torque 85.4 Nm; thermal loss 0.11 kW.
Action: Keep the 0.5 hp path only if thermal validation passes with margin.
Assumption: Heavy shock profile and >16 h/day duty cycle.
Process: Service factor rises sharply, increasing required rated torque and cost.
Outcome: Most failures come from underestimating shock and lubrication degradation, not nominal ratio mismatch.
Action: Use reinforced housing and validated lubrication interval before freeze.
Assumption: Low shock but strict repeatability and low backlash demand.
Process: Ratio can pass, but positioning quality still depends on backlash class and stiffness.
Outcome: Torque may pass while accuracy still fails if preload and class are not specified.
Action: Request backlash class and torsional stiffness test reports in RFQ.
Assumption: Stakeholder request says "1 1 worm gearbox" or "1 4hp worm gearbox" and keeps output speed close to motor speed.
Process: Use the 1:1 boundary section to distinguish keyword alias handling from real no-reduction mechanical requirements.
Outcome: If true 1:1 is confirmed, bevel/direct baselines typically provide better efficiency references while worm self-locking remains conditional.
Action: Require architecture justification memo and side-by-side energy/safety comparison before freezing a worm choice.
| Item | Must Have | If Missing |
|---|---|---|
| Continuous torque curve | Vendor test data by speed and temperature | Thermal failure risk is unknown |
| Backlash class | Numeric class + test method | Positioning quality cannot be guaranteed |
| Lubrication spec | Oil grade and maintenance cycle | Field life drops unpredictably |
| Slide-out service package | OEM model traceability + installation/removal kit method + mounting-position oil refill instruction | Disassembly force path and restart condition cannot be validated safely |
| Shock and duty confirmation | Application load cycle evidence | Service factor becomes guesswork |
Core conclusions in this page map to traceable sources. Last evidence refresh: April 29, 2026.
Planned review cadence: every 6 months, or earlier when standards, supplier curves, or thermal assumptions change.
AGMA / MPMA · Provides worm-reducer rating scope (speed/sliding-velocity limits) and confirms thermal capacity, service factor, lubrication, and self-locking are explicit parts of the method.
SEW-EURODRIVE · Documents that worm-stage efficiency is ratio/speed/temperature dependent and can drop below 0.5 at very high ratios.
SEW-EURODRIVE · Defines run-in effects, including typical 48-hour duration and ratio-dependent efficiency reduction (around 2% to 12% in published tables).
SEW-EURODRIVE · Defines static self-locking condition at forward efficiency <= 0.5 and states it must not be the sole safety function for hoists.
SEW-EURODRIVE · Provides right-angle alternative efficiency context: up to 96% (3-stage), 97% (2-stage), and 98% (1-stage) for R/F/K families.
SEW-EURODRIVE · Provides publicly listed operating envelopes: ratio 3.97-288, motor-adapter power 0.12-30 kW, torque up to 4300 Nm, and S..7p efficiency uplift claims.
ISO · Sets a scope boundary: this series is for spur/helical cylindrical gears and explicitly states limits and non-applicable failure conditions.
OSHA / eCFR · Defines U.S. action and control thresholds used in factory risk reviews: 85 dBA hearing-conservation trigger and Table G-16 90 dBA at 8 h.
CDC / NIOSH · Provides 85 dBA REL and the 3 dBA exchange-rate rule used for conservative noise-exposure planning.
NIST · Provides the unit anchor for this page scope check: 1 hp = 745.6999 W, so 0.5 hp ~= 0.373 kW.
UK HSE · Adds EU-derived operational thresholds (80/85/87 dB(A)) to cross-check multinational plant rollouts.
OSHA / eCFR · Defines maintenance safety controls for unexpected energization/startup and stored energy release during servicing/disassembly, including periodic inspection of energy-control procedures.
OSHA / eCFR · Requires guarding against hazards from point-of-operation, ingoing nip points, and rotating parts when machine power is restored after maintenance.
ISO · Covers unexpected start-up prevention for electrical/hydraulic/pneumatic/stored/external energy and clarifies machine-specific means must be set by risk assessment or type-C standards.
SEW-EURODRIVE · Provides installation/removal kit details, tightening torques, hollow-shaft disassembly process, reduced-backlash availability limits, and lubrication/mounting-position dependencies.
NORD DRIVESYSTEMS · Documents practical worm-stage ratio envelope (about i = 4 to 100), efficiency sensitivity at high ratios, and conditional self-locking behavior only for certain toothings under reverse power flow.
NORD DRIVESYSTEMS · Provides right-angle baseline for true 1:1 discussions: per-stage ratios usually 1:1 to 1:10, efficiency around 96% to 98%, and no inherent self-locking.
U.S. Energy Information Administration (EIA) · Supplies U.S. industrial electricity price markers used for operating-cost sensitivity in this page (annual 2025 and Jan/Feb 2026 values).
Bonfiglioli · Shows worm-family ratio distributions in discrete sets and repeated 7 <= i <= 100 ranges across multiple frame combinations.
Catalog table extraction can vary by OCR parser; confirm exact frame-specific rows during RFQ.
Grouped by decision intent. This section explicitly answers both "worm gearbox", "0.5 hp worm gearbox", "1 4hp worm gearbox", "1 1 worm gearbox", and "00611e worm gearbox slide out".
Use the checker result as the first filter, then close the loop with supplier thermal/backlash evidence before procurement freeze.