Descrição
SL300 Heavy-Industrial Cross-Slider Oldham Coupling — 300 mm Cast-Iron Hub for Slow-Speed High-Torque Mill Drives
O SL300 industrial Oldham coupling introduces an important transition in the SL family. With 13 000 N·m rated torque, 300 mm hub OD, 120–130 mm bore range, and — for the first time — a permissible speed of 100 r/min rather than 250 r/min, the SL300 is sized specifically for the slow-speed, high-torque duty class that dominates large mill main drives, kiln-section inputs, and the heavier-end hydropower auxiliary trains. The reduction in permissible speed is not an arbitrary catalogue choice: it reflects the engineering reality that as coupling mass grows toward 100 kg and centrifugal loads grow with the cube of diameter, the upper rotational-speed limit must be reduced to maintain reasonable hub-stress and bearing-load profiles in the host equipment.
For the integrator specifying a coupling at the SL300’s size class, the engineering question shifts from “what is the highest-rated coupling for my torque” to “what is the appropriate balance of torque, misalignment envelope, and rotational speed for my application class”. The SL300’s 13 000 N·m at 100 r/min envelope translates to approximately 135 kW of continuous mechanical power — a duty class that includes large ball-mill and SAG-mill auxiliary input drives, primary cement-kiln burner-section inputs, large bulk-material yard-conveyor drives, and the slower-end heavy process-mixer outputs. These applications share a common engineering profile: high steady-state torque, relatively low rotational speed, and a misalignment budget that grows with the substantial frame deflections of large fabricated structures.
Especificações
| Parâmetro | Valor |
|---|---|
| Modelo | SL300 |
| Torque Nominal (Tn) | 13 000 N·m |
| Velocidade permitida (n) | 100 r/min |
| Alcance do furo (d) | 120 – 130 mm |
| Outside Diameter (D) | 300 mm |
| Hub Bore Diameter (D₁) | 180 mm |
| Overall Length (L) | 210 mm |
| Slider Plate Thickness (H) | 43 mm |
| Slider Clearance (S) | 1.0 mm |
| Moment of Inertia | 4.3 kg·m² |
| Massa | 111 kg |
| Desalinhamento radial (Δy) | 4.8 mm |
| Desalinhamento angular (Δα) | 0,5° |
| Desalinhamento axial (Δx) | 4.2 mm |
| Engate do eixo | Keyway or taper-bushed |
| Lubrificação | Grease (re-pack 6-monthly) |
Materiais
QT500-7 Ductile-Iron Hubs (Standard)
Hub specification is QT500-7 nodular cast iron with full stress-relief annealing prior to all machining operations. Each hub masses approximately 52 kg. The hub-section thickness has been engineered with a 3× safety factor against the 13 000 N·m rated peak — actual peak-torque capacity before permanent-deformation risk is approximately 39 000 N·m. For ultra-aggressive shock-load profiles, an upgrade to QT600-3 cast steel is offered through engineering review.
43 mm Heavy Steel Slider
The 43 mm slider thickness — up from 33 mm on smaller SL family members — reflects the slow-speed, high-torque duty profile. Standard induction-hardened 45-steel slider; 40Cr alloyed-steel variant for reversal-duty deployments. Slider mass is approximately 13 kg; pre-machined lifting eyelets are routinely supplied for hoist-supported field service.
Taper-Bushed Mounting (Recommended Standard)
At the SL300 size, taper-bushed mounting via locking-assembly families is the engineering recommended standard rather than an upgrade option. The locking-assembly approach eliminates the keyway-shear failure mode entirely under the realistic shock-load profile of large mill drives. Keyway mounting remains available for cost-sensitive light-duty applications, but engineering does not recommend it for cement-kiln, mining-mill, or steel-mill installations.
Slow-Speed High-Torque Engineering
The shift from 250 r/min to 100 r/min permissible speed is more than a numerical change. It reflects the duty profile of equipment classes that operate in the slow-speed, high-torque envelope: ball mills, SAG mills, primary kilns, large slow-process mixers, and heavy bulk-handling conveyors with steep incline ratios. These equipment classes share an engineering feature that the SL300 is optimised for — the torque is steady-state-dominant rather than dynamic-event-dominant. The coupling needs to transmit a very high torque continuously, with shock-load events accommodated by safety factor, rather than transmit a moderate torque with the rotational-speed envelope dominated by precision-balance and centrifugal-loading considerations.
This engineering profile aligns naturally with the cross-slider architecture. At 100 r/min, the slider’s sliding-friction work over a given misalignment magnitude is approximately 2.5× lower than the same misalignment at 250 r/min. The reduced sliding-friction work translates directly into extended slider service life — typical SL300 slider replacement intervals span 8–10 years even under aggressive mill-duty profiles. For owners of cement-mill and mining-mill installations, this aligns slider-replacement scheduling with the natural cycle of major plant overhauls, eliminating the slider-replacement event from the routine maintenance touch-point list entirely.
For broader engineering discussion of slow-speed high-torque coupling selection, see Ever-power’s heavy-industrial coupling resource portal.
Aplicações industriais
⛰️ Ball-Mill & SAG-Mill Inputs
Auxiliary input couplings on large ball mills and SAG mills in minerals processing. The 4.8 mm misalignment envelope accommodates the substantial mill-shell deflection under loaded operation.
Cement-Kiln Section Inputs
Drive coupling between motor and reduction-input of cement-kiln rotating-section drives. Slow-speed duty aligns with kiln operating envelope; misalignment tolerance absorbs kiln-shell thermal expansion.
Hydropower Main-Auxiliary
Gate-actuator, intake-cleaning, and main-trash-rack drives on 25–50 MW hydropower stations. Long-cycle reliability across the 30+ year design life of hydropower infrastructure.
Heavy Bulk-Yard Conveyors
Stockyard reclaimer-conveyor and outbound-cargo terminal drives on coal, iron-ore, and minerals export terminals. Misalignment tolerance handles long-conveyor frame deflection.
Slow-Speed Process Mixers
Large industrial-mixer impeller drives in chemical, pharmaceutical-bulk, and metallurgical industries. Constant-velocity output preserves the mixing-uniformity profile that determines product-quality consistency.
⛏️ Mining-Hoist Main Auxiliary
Large mining-shaft hoist auxiliary drives in underground operations. Zero-backlash transmission supports safety-interlock integration; gradual failure mode supports SIL 1/2 application.
Por que escolher Ever-Power?
Qualidade e Conformidade
SL300 production runs under ISO 9001:2015 with full melt-traceability per cast-iron heat. Standard documentation pack covers RoHS, ALCANÇAR, CE conformity, plus FMEA documentation. For mining and minerals-processing customers, supplementary safety-case integration documentation is available. For hydropower deployments, EN ISO 12944 corrosivity-class compatibility documentation is supplied.
Customisation
Catalogue bore range 120–130 mm; oversized variants up to 135 mm produced under engineering review. Imperial-bore variants (4-3/4″, 4-7/8″, 5″, 5-1/8″) supported for North American export markets. QT500-7 ductile-iron hub is the engineering recommended standard at this size; QT600-3 cast-steel variant available for ultra-aggressive shock-load applications. Taper-bushed mounting via standard locking-assembly families is documented and routinely supplied.
Critical-Asset Aftermarket
SL300 slider plates and 40Cr alloy variants stocked for 2-business-day shipment. Mass per coupling 111 kg; sea-freight in heavy-duty reinforced crating with secondary shock-absorbing packaging. English-speaking engineering desk responds within 24 horas. Pre-negotiated emergency-replacement protocols guarantee 5-working-day delivery for critical-asset customers.
Avaliações de clientes e estudos de caso
★★★★★
Luxembourg — Specialty-Steel Producer
Utilizado em: Ladle-furnace stirring-drive coupling on a specialty-steel production line.
Opinião: “Continuous-duty mixing of molten-metal ladle stir loops at elevated ambient. The SL300 with QT500 hubs, taper-bushed mounting, and synthetic high-temperature grease has now passed 6 years of three-shift duty with one slider replacement during a planned ladle-furnace overhaul. Cast-iron hubs show no measurable change in dimensional accuracy after extended thermal-cycle exposure. Excellent senior-engineered specification.”
★★★★★
Brunei — LNG-Terminal Operator
Utilizado em: Boil-off-gas compressor auxiliary drive on a coastal LNG export terminal.
Opinião: “Coastal-salt ambient and continuous LNG-process duty had been challenging for every flexible-coupling architecture we tried. The SL300 with QT500 hubs and IP54 sealed coupling guard has handled 5 years of continuous duty with no unplanned events. The FMEA documentation that came with the specification was material in our DCS safety-case integration review — saved approximately 2 months of compliance work.”
★★★★☆
Bahrain — Aluminium-Smelter Operator
Utilizado em: Anode-handling crane auxiliary drive on a primary-aluminium smelter.
Opinião: “High-ambient temperature and routine shock-load duty from crane indexing. The SL300 has now passed 4 years with one scheduled slider replacement. Knock one star only because the heavy 111 kg mass made installation challenging at our crane-mast location — required pre-arranged hoist support that added a half-shift to initial commissioning. Operational performance once installed has been excellent.”
Perguntas frequentes
Why is permissible speed 100 r/min instead of 250 r/min?
As coupling mass and outside-diameter grow, the centrifugal load on the slider’s outer regions grows with the cube of diameter. To maintain reasonable slider-stress profile and host-bearing-load envelope, the catalogue permissible speed is reduced. At 100 r/min the SL300’s outer-rim speed is approximately 1.6 m/s — well within established sliding-velocity envelopes for grease-lubricated metallic interfaces.
Can the SL300 operate above 100 r/min?
For applications requiring operation up to 150 r/min, a special-balance variant with ISO 1940 G2.5 precision balance and supplementary slider clearance verification is documented and available — please specify at order entry with the actual operating-speed profile. For operation above 150 r/min the SL300 is not the appropriate selection; consult engineering for an alternative within the smaller SL250 or SL260 family.
What is the recommended TPM/RCM maintenance schedule?
For Total Productive Maintenance or Reliability-Centred Maintenance frameworks, the recommended SL300 schedule is: monthly visual inspection of coupling-guard integrity; quarterly grease-port inspection for evidence of leakage; semi-annual grease repack; annual slider-wear inspection during planned shutdown; multi-year slider replacement during major plant overhauls. This schedule integrates naturally with cement-mill, mining-mill, and large-plant maintenance cycles.
How is the SL300 shipped internationally?
Sea-freight is the standard logistics mode at this mass class. Coupling assemblies ship in heavy-duty reinforced wooden crates with secondary shock-absorbing foam packaging. Net mass per crate is 111 kg plus 25 kg of packaging; gross mass 136 kg. For consolidated multi-coupling shipments, palletised arrangements are supported. Air-freight is available for emergency replacement at substantial cost premium.
What aftermarket protocols apply for critical-asset customers?
For continuous-production critical-asset customers (large cement plants, primary minerals processors, integrated steel mills), Ever-power offers pre-negotiated emergency-replacement protocols: 5-working-day delivery of complete SL300 couplings or slider plates from confirmed PO; air-freight logistics pre-arranged to nominated customer hub; buffer-stock programmes at customer-nominated 3PL warehouses; and annual maintenance-review consultations. Programme terms are negotiated with the sales desk based on installed-base size and demand profile.
Quote SL300 for Slow-Speed Heavy-Industrial Drives
For large mill main, cement-kiln section, hydropower main-auxiliary, and heavy bulk-yard conveyor applications, the SL300 is the senior-engineered specification of choice for slow-speed high-torque drives. Browse the wider SL series catalogue, read about Ever-power’s critical-asset supply capability, or move directly to a B2B enquiry below.
