Description
SL320 Heavy-Industrial Cross-Slider Oldham Coupling — 320 mm Cast-Iron Hub for Minerals-Processing and Port-Terminal Drives
The SL320 industrial Oldham coupling sits in the heart of the slow-speed, high-torque envelope. With 16 000 N·m rated torque, 320 mm hub OD, 130–140 mm bore range, and 100 r/min permissible speed, the SL320 transmits approximately 170–200 kW of continuous mechanical power. This is the duty profile of heavy minerals-processing mill drives, large cement-kiln auxiliary inputs, primary port-terminal stacker/reclaimer main-auxiliary drives, and the larger end of metallurgical-process slow-speed mixers. At this size class, the coupling specification is invariably a senior-engineering decision, supported by reliability analysis, maintenance-economics evaluation, and full lifecycle-cost modelling over a 20–30 year horizon.
The SL320’s place in the catalogue reflects an engineering reality of large industrial drives: between the 13 000 N·m SL300 and the 20 000 N·m SL340, there is a substantial population of process equipment that needs exactly the 16 000 N·m envelope — neither the over-specification cost of a larger coupling nor the inadequate margin of a smaller one. For minerals-processing operators specifically, the SL320 sits at the size sweet-spot for secondary ball-mill auxiliaries, large flotation-cell agitator drives, and the heavier-end thickener-rake mechanisms that dominate the back-end of mineral concentration plants. These applications share a common engineering challenge: very steady torque at low speed, with substantial frame-deflection misalignment under load, and 24/7 production-mode operation across decade-class service intervals.
Specifications
| Parameter | Value |
|---|---|
| Model | SL320 |
| Nominal Torque (Tn) | 16 000 N·m |
| Permissible Speed (n) | 100 r/min |
| Bore Range (d) | 130 – 140 mm |
| Outside Diameter (D) | 320 mm |
| Hub Bore Diameter (D₁) | 190 mm |
| Overall Length (L) | 220 mm |
| Slider Plate Thickness (H) | 43 mm |
| Slider Clearance (S) | 1.0 mm |
| Moment of Inertia | 5.7 kg·m² |
| Mass | 129 kg |
| Radial Misalignment (Δy) | 5.2 mm |
| Angular Misalignment (Δα) | 0.5° |
| Axial Misalignment (Δx) | 4.6 mm |
| Shaft Engagement | Taper-bushed standard |
| Lubrication | Grease (re-pack 6-monthly) |
Materials
QT500-7 Ductile-Iron Hubs (Standard)
Hubs are QT500-7 nodular cast iron with stress-relief annealing. Each hub masses approximately 60 kg, with section thickness engineered to a 3× safety factor against the rated 16 000 N·m peak. For ultra-aggressive minerals-processing shock-load profiles, QT600-3 cast-steel hub variant is documented and available under engineering review with a 6-week extended lead time.
43 mm Heavy Steel Slider
43 mm thick induction-hardened 45-steel cross-slider standard; 40Cr alloyed-steel slider variant for reversal-duty and aggressive abrasive-ambient minerals-processing deployments. Slider masses approximately 16 kg; pre-machined lifting eyelets supplied as standard for hoist-supported field service. Bronze CuSn10 slider available for electrical-isolation applications.
Taper-Bushed Mounting (Standard)
At the SL320 size, taper-bushed mounting via standard locking-assembly families (RINGFEDER 7012, KTR-Clampex, Trantorque) is the engineering standard rather than a custom option. The H7-reamed keyway variant remains available for cost-sensitive light-duty service, but is not the engineering recommendation for minerals-processing, cement-kiln, or port-terminal deployments.
The Engineering Profile of Minerals Processing
Minerals-processing equipment occupies a distinctive engineering niche. Production is continuous and asset-utilisation-driven — typical operational targets are 92–96 % available hours per year, leaving only 350–700 hours per year for all planned maintenance combined. The drive train sees steady-state torque interrupted by routine 1.5–2× rated-torque shock events from inhomogeneous ore feed, oversize-rock impacts, and the start-loaded-conveyor profile of granular-material handling. Ambient conditions are abrasive (rock dust), corrosive (process liquors), and often thermally extreme (open-pit operations spanning seasonal temperature ranges of -30 °C to +50 °C).
The SL320’s design addresses each of these challenges through specific architectural choices. QT500 ductile-iron hubs deliver shock-load endurance through superior fracture toughness. Sealed coupling guard to IP54 isolates the slider lubrication from abrasive ambient. Synthetic polyalphaolefin grease specification (catalogue option) maintains viscosity across the operating-temperature window. Taper-bushed mounting eliminates the keyway-shear failure mode under realistic shock-load profile. And the field-replaceable slider plate allows scheduled replacement during major plant turnarounds — typically 4-year cycles for ball-mill, 5-year cycles for thickener-rake mechanisms — eliminating coupling replacement from the operational maintenance touch-point list.
For further engineering background on minerals-processing coupling selection, see Ever-power’s specialty industries portal.
Industry Applications
⛰️ Secondary Ball-Mill Auxiliary
Auxiliary input couplings on secondary ball-mill installations in minerals-processing plants. Slow-speed envelope aligns with mill operating profile; misalignment tolerance handles substantial mill-shell deflection.
Cement-Kiln Auxiliary Inputs
Drive coupling on cement-kiln auxiliary rotating-section drives. Misalignment tolerance absorbs kiln-shell thermal expansion across the burner-zone temperature gradient.
Port-Terminal Main Auxiliary
Stacker-reclaimer luffing and slewing drives on bulk-cargo port-terminal infrastructure. Coastal-salt ambient compatibility through QT500 hubs and synthetic-grease specification.
Large Flotation-Cell Agitators
Drive coupling on large minerals-flotation cell agitator drives. Slow-speed steady-state operation; zero-backlash transmission supports flotation-process consistency requirements.
⚙️ Heavy Thickener-Rake Drives
Drive coupling on large thickener-rake mechanisms in minerals concentration and metallurgical-leach plant operations. Long-cycle reliability across the 15–20 year design life of typical thickener installations.
Large Water-Industry Pumps
Drive coupling on large municipal water-treatment, irrigation, and flood-control pump installations. Long-cycle reliability across the 30+ year design life of water-infrastructure assets.
Why Choose Ever-power
Quality & Compliance
SL320 production runs under ISO 9001:2015 with full melt-traceability per cast-iron heat. Documentation pack covers RoHS, REACH, CE conformity, plus FMEA documentation. For minerals-processing customers, supplementary documentation covering shock-load profile compatibility and SAG/Ball-mill-specific duty-cycle analysis is available. For port-terminal customers, NACE MR0175 sour-service compatibility and EN ISO 12944 corrosivity-class C5 documentation can be supplied.
Customisation
Catalogue bore range 130–140 mm; oversized variants up to 145 mm produced under engineering review. Imperial-bore variants (5-1/8″, 5-1/4″, 5-3/8″, 5-1/2″) supported for North American export markets. QT500-7 ductile-iron hub is the engineering recommended standard; QT600-3 cast-steel variant for ultra-aggressive shock-load applications. Taper-bushed mounting via standard locking-assembly families is the documented standard.
Critical-Asset Aftermarket
SL320 slider plates and 40Cr alloy variants stocked for 2-business-day shipment. Mass per coupling 129 kg; sea-freight in heavy-duty reinforced crating with secondary shock-absorbing packaging. English-speaking engineering desk responds within 24 hours. Pre-negotiated emergency-replacement protocols guarantee 5-working-day delivery from confirmed PO.
Customer Reviews & Case Studies
★★★★★
Oman — Copper-Concentrator Operation
Used in: Secondary-grinding ball-mill auxiliary input drive on a 35 kt/d copper-concentrator plant.
Feedback: “Specified the SL320 with QT500 hubs, taper-bushed mounting, and 40Cr alloy slider after a comprehensive engineering review against gear-coupling and disc-pack alternatives. Six years of three-shift duty with two slider replacements during major plant overhauls. Asset-utilisation impact has been excellent — zero coupling-attributable unplanned events. Specification will be applied across our next two concentrator plant expansions.”
★★★★★
Bolivia — Tin-Mine Concentrator
Used in: Flotation-cell agitator-drive coupling on a tin-mineral concentrator operation.
Feedback: “High-altitude operation (4 200 m elevation) introduces atypical thermal and lubrication challenges. The SL320 with synthetic-grease specification has handled this without issue across 5 years of continuous duty. Engineering response to our altitude-specific commissioning questions was excellent — within 24 hours we had clear guidance on grease-vapour-pressure compatibility and bearing-load adjustments. Best supplier engineering interaction we have had on this site.”
★★★★☆
Paraguay — Soy-Crushing Plant Operator
Used in: Soybean-conditioner main-drive coupling on a 2 500 t/d soy-crushing facility.
Feedback: “Continuous-process duty with significant elevated-temperature ambient at the conditioner. The SL320 has now passed 4 years of continuous duty without unplanned events. Knock one star only because emergency-replacement protocol delivery time to our inland location took 9 working days during one urgent event — the protocol commits to 5 working days but in our remote case the air-freight logistics extended this slightly. Otherwise excellent.”
Frequently Asked Questions
How does the SL320 perform in high-altitude installations?
Reduced atmospheric pressure at altitude affects grease vapour-pressure profiles and bearing-load distribution. For installations above 3 000 m elevation, specify a synthetic polyalphaolefin grease with documented low-vapour-pressure profile, and please consult Ever-power engineering for an altitude-compatibility review. The cast-iron and steel material specifications themselves operate without de-rating across the full altitude range.
What is the documented shock-load endurance for minerals-processing?
With QT500 ductile-iron hubs, the SL320 carries a documented 3× rated-torque shock-load capacity (48 000 N·m peak instantaneous) without permanent damage, and a routine 2× rated-torque event tolerance (32 000 N·m) without measurable accumulated damage over a 20-year service life. With QT600-3 cast-steel hub upgrade, these margins improve by approximately 25 %.
Is the SL320 supported under 24/7 production-mode service?
Yes — 24/7 continuous-production operation is the normal duty profile for this size class. The semi-annual grease-repack interval is compatible with typical asset-utilisation targets of 92–96 % yearly availability, and slider-replacement intervals (8–10 years under typical mill duty) align naturally with major plant turnaround cycles. Production-mode duty does not de-rate any catalogue specification.
What lifecycle-cost framework should I use to evaluate the SL320?
For a 20-year operating-cost evaluation, include: (1) coupling acquisition cost; (2) installation cost (typically 8–12 hours of skilled labour); (3) annual semi-annual grease-repack labour (1 hour each, twice yearly); (4) every 8–10 year slider replacement at planned shutdown (90 minutes of skilled labour, plus slider part cost); (5) annual inspection labour (15 minutes). Total 20-year cost typically ranks the SL320 below competing flexible-coupling architectures by a clear margin.
Is supplier engineering support available during commissioning?
Yes. Ever-power engineering responds within 24 hours to commissioning questions in English, with extended support windows available for high-volume OEM partners. For major capital-equipment installations, remote video-conference support during commissioning is offered without additional charge for critical-asset customers. On-site supervision can be arranged for major installations under separate commercial terms.
Quote SL320 for Heavy Minerals-Processing Drives
For secondary ball-mill auxiliary, cement-kiln auxiliary, large port-terminal, flotation-cell, and heavy thickener-rake applications, the SL320 is Ever-power’s senior-engineered specification for minerals-processing slow-speed high-torque duty. Explore the wider SL series catalogue, learn about Ever-power’s minerals-processing supply capability, or move directly to a B2B enquiry below.
