{"id":776,"date":"2026-06-23T09:47:03","date_gmt":"2026-06-23T09:47:03","guid":{"rendered":"https:\/\/oldhamcoupling.net\/product\/sl280-industrial-oldham-coupling\/"},"modified":"2026-06-24T08:47:43","modified_gmt":"2026-06-24T08:47:43","slug":"sl280-industrial-oldham-coupling","status":"publish","type":"product","link":"https:\/\/oldhamcoupling.net\/ja\/product\/sl280-industrial-oldham-coupling\/","title":{"rendered":"SL280 Industrial Oldham Coupling"},"content":{"rendered":"
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SL280 Heavy-Industrial Cross-Slider Oldham Coupling \u2014 280 mm Cast-Iron Hub at the Threshold of Ultra-Heavy Duty<\/h2>\n

The SL280 industrial Oldham coupling<\/strong> sits at the threshold between mid-heavy and ultra-heavy industrial drive duty. At 10 000 N\u00b7m rated torque \u2014 the first five-figure rating in the SL family \u2014 280 mm hub OD, 110\u2013120 mm bore range, and 250 r\/min permissible speed, the SL280 transmits 250\u2013330 kW of continuous mechanical power. This is the duty class of large process-mill auxiliaries, marine main-shaft auxiliary trains, primary mining-conveyor head drives, and the heavier-end metallurgical-process pumps. At this scale, the SL280 is the kind of asset that gets specified by name in the plant’s reliability-engineering documentation and tracked individually on the maintenance-management system across decades of installed life.<\/p>\n

For the engineer considering the SL280 against alternatives \u2014 large gear couplings, double-flex disc-pack couplings, large fluid couplings, or oversized elastomer-spider designs \u2014 the SL280’s value proposition rests on three architectural pillars that the alternatives cannot simultaneously deliver. First, the misalignment envelope: 4.4 mm radial offset, 0.5\u00b0 angular, 3.8 mm axial. No comparable disc-pack or precision-gear coupling reaches even half this envelope without going to a multi-element spacer-shaft arrangement. Second, the failure mode: gradual wear of an inspectable metallic slider, not catastrophic-event failure of a fatigued elastomer or disc-pack. Third, field serviceability: slider replacement during planned shutdowns without precision laser-alignment, hubs remaining keyed to their shafts. These three properties define the SL280’s place in continuous-production-plant engineering.<\/p>\n

Specifications<\/h3>\n
\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Parameter<\/th>\nValue<\/th>\n<\/tr>\n<\/thead>\n
Model<\/td>\nSL280<\/td>\n<\/tr>\n
Nominal Torque (Tn)<\/td>\n10 000 N\u00b7m<\/td>\n<\/tr>\n
Permissible Speed (n)<\/td>\n250 r\/min<\/td>\n<\/tr>\n
Bore Range (d)<\/td>\n110 \u2013 120 mm<\/td>\n<\/tr>\n
Outside Diameter (D)<\/td>\n280 mm<\/td>\n<\/tr>\n
Hub Bore Diameter (D\u2081)<\/td>\n170 mm<\/td>\n<\/tr>\n
Overall Length (L)<\/td>\n200 mm<\/td>\n<\/tr>\n
Slider Plate Thickness (H)<\/td>\n33 mm<\/td>\n<\/tr>\n
Slider Clearance (S)<\/td>\n1.0 mm<\/td>\n<\/tr>\n
Moment of Inertia<\/td>\n3.0 kg\u00b7m\u00b2<\/td>\n<\/tr>\n
Mass<\/td>\n94.3 kg<\/td>\n<\/tr>\n
Radial Misalignment (\u0394y)<\/td>\n4.4 mm<\/td>\n<\/tr>\n
Angular Misalignment (\u0394\u03b1)<\/td>\n0.5\u00b0<\/td>\n<\/tr>\n
Axial Misalignment (\u0394x)<\/td>\n3.8 mm<\/td>\n<\/tr>\n
Shaft Engagement<\/td>\nKeyway or taper-bushed<\/td>\n<\/tr>\n
Lubrication<\/td>\nGrease (re-pack 6-monthly)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

\"SL280<\/p>\n

Materials<\/h3>\n
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QT500-7 Ductile-Iron Hubs (Standard)<\/h4>\n

At SL280 size the QT500-7 ductile-iron hub variant is the documented standard specification. Each hub masses approximately 45 kg, with section thickness engineered to a 3\u00d7 safety factor against the rated 10 000 N\u00b7m peak. The spheroidal-graphite microstructure’s superior fracture toughness is non-negotiable at this duty class \u2014 shock-load endurance is the dominant reliability vector, and grey-iron hubs simply do not provide adequate margin against routine 1.5\u20132\u00d7 rated-torque events.<\/p>\n<\/p><\/div>\n

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Heavy Hardened Steel Slider<\/h4>\n

33 mm thick induction-hardened 45-steel cross-slider as standard; 40Cr alloyed-steel slider with HRC 55 surface hardness for reversal-duty deployments (marine winches, hot-strip-mill auxiliaries). At ~8 kg, the slider becomes a non-trivial handling item during field replacement; Ever-power supplies dedicated lifting eyelets pre-machined on customer request for hoist-supported maintenance.<\/p>\n<\/p><\/div>\n

\n

Keyway or Taper-Bushed Mounting<\/h4>\n

Standard catalogue is H7-reamed bore with parallel keyway to GB\/T 1096 and M20 set-screw. For mining-conveyor, large-mill, and marine deployments, taper-bushed mounting via RINGFEDER 7012, Trantorque, or KTR-Clampex locking-assembly families is the documented engineering best practice \u2014 eliminating keyway shear entirely under the routine shock-load profile. The SL280 hub geometry accepts these locking-assembly families without secondary machining.<\/p>\n<\/p><\/div>\n<\/div>\n

Crossing the Five-Figure Torque Threshold<\/h3>\n

The transition from sub-10 000 N\u00b7m to 10 000 N\u00b7m and above is not merely a numerical step. At this duty class, the host motor is typically a 315\u2013400 kW induction unit with substantial starting-torque headroom. The connected gear-reducer or fluid coupling typically has its own reflected-inertia profile that adds to the coupling’s effective load during start-up transients. And the driven equipment is often a process mill, a large pump, or a heavy conveyor with a significant inrush-torque requirement during loaded start. The coupling must transmit all of this while absorbing the realistic misalignment envelope of large industrial frame fabrications \u2014 typically 2\u20133 mm of parallel offset that accumulates from machine-base settling, thermal growth, and bearing-housing tolerance stack-up.<\/p>\n

The SL280’s architecture handles this combination of load and misalignment without flexure of any metallic component. The 4.4 mm parallel-misalignment envelope provides comfortable margin against realistic frame tolerance, even with thermal-growth excursions during plant warm-up. The 3.8 mm axial-displacement allowance forgives the cumulative expansion of long shaft trains as they reach operating temperature. And the cast-iron-plus-steel material stack absorbs shock-load events through their substantial section modulus, with no fatigue mechanism in the load path. The combined effect is a coupling that exhibits a strikingly flat reliability profile across years of continuous-production duty \u2014 precisely the failure characteristic that plant reliability engineering values.<\/p>\n

For broader engineering background on ultra-heavy industrial cross-slider applications, our heavy-coupling engineering portal<\/a> covers the kinematic, tribological, and structural-analysis frameworks in detail.<\/p>\n

\"SL280<\/p>\n

Industry Applications<\/h3>\n
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<\/span> Large Process-Mill Auxiliaries<\/h4>\n

Auxiliary drive trains on large ball mills, SAG mills, and roller-press auxiliaries in cement and minerals processing. Misalignment tolerance handles the substantial frame deflection of large mill structures under load.<\/p>\n<\/p><\/div>\n

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<\/span> Marine Main-Shaft Auxiliary<\/h4>\n

Auxiliary drives on large bow-thrusters, stern-thrusters, and main-shaft brake actuators in commercial vessels. QT500 ductile-iron hubs resist the saltwater-spray ambient of marine engineering rooms.<\/p>\n<\/p><\/div>\n

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\u26cf\ufe0f<\/span> Primary Mining-Conveyor Heads<\/h4>\n

Head-pulley drive couplings on heavy overland mining conveyors (1400\u20131800 mm width). Slider absorbs the inrush profile of loaded-conveyor start without flexure of cast-iron sections.<\/p>\n<\/p><\/div>\n

\n

\ufe0f<\/span> Heavy Process-Industry Pumps<\/h4>\n

Large centrifugal-pump drives in petrochemical, fertiliser, and large desalination installations. The 4.4 mm misalignment envelope absorbs the thermal-growth profile of long process-pump shaft trains.<\/p>\n<\/p><\/div>\n

\n

<\/span> Port & Terminal Equipment<\/h4>\n

Stacker, reclaimer, and ship-loader auxiliary drives in bulk-material port terminals. Salt-air-tolerant QT500 hubs and synthetic-grease specification support coastal infrastructure reliability.<\/p>\n<\/p><\/div>\n

\n

\u26a1<\/span> Power-Station Auxiliaries<\/h4>\n

Boiler-feed pump and forced-draft fan drives on thermal-power-station auxiliary trains. Long-cycle reliability across the 30+ year design life of power-station infrastructure.<\/p>\n<\/p><\/div>\n<\/div>\n

Why Choose Ever-power<\/h3>\n
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Quality & Compliance<\/h4>\n

SL280 production runs under ISO 9001:2015<\/strong> with full melt-traceability per cast-iron heat. Documentation pack includes RoHS<\/strong>, REACH<\/strong>, and CE<\/strong> conformity declarations as standard. For marine customers, NACE MR0175 sour-service compatibility statements and Lloyd’s Register or DNV-GL type-approval documentation can be supplied with appropriate engineering review. For power-station customers, supplementary documentation covering 30-year design-life fatigue analysis is available.<\/p>\n

Customisation<\/h4>\n

Catalogue bore range 110\u2013120 mm; oversized variants up to 125 mm produced under engineering review. Imperial-bore variants (4-3\/8″, 4-1\/2″, 4-3\/4″) supported for North American export markets. QT500 ductile-iron hub is the engineering recommended specification. Taper-bushed mounting via standard locking-assembly families is documented and routinely supplied for shock-load installations.<\/p>\n

Critical-Asset Aftermarket<\/h4>\n

SL280 slider plates and 40Cr alloy variants stocked for 2-business-day shipment. Mass per coupling 94.3 kg; sea-freight in heavy-duty reinforced crating with secondary shock-absorbing foam standard. English-speaking engineering desk responds within 24 hours<\/strong>. For continuous-production critical-asset customers, pre-negotiated emergency-replacement protocols guarantee 5-working-day delivery from confirmed PO.<\/p>\n<\/div>\n

\"Ever-power<\/p>\n

Customer Reviews & Case Studies<\/h3>\n
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\u2605\u2605\u2605\u2605\u2605<\/p>\n

Cyprus \u2014 Aggregate-Quarry Operator<\/h4>\n

Used in:<\/em> Primary-conveyor head-pulley drive on a limestone quarry producing 1.2 Mt\/y.<\/p>\n

Feedback:<\/em> “Loaded-conveyor start under island-summer ambient was a continuous reliability headache with our original spider-coupling specification \u2014 average service interval was 14 months. The SL280 with QT500 hubs and taper-bushed mounting has now passed 6 years with one slider replacement during a planned quarry shutdown. Total ownership economics are clearly favourable; we have standardised this size class across the operation.”<\/p>\n<\/p><\/div>\n

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\u2605\u2605\u2605\u2605\u2605<\/p>\n

Malta \u2014 Port-Terminal Operator<\/h4>\n

Used in:<\/em> Stacker-reclaimer auxiliary drive on a bulk-cargo terminal.<\/p>\n

Feedback:<\/em> “Sea-air ambient and constant high-utilisation duty had been challenging for every flexible-coupling architecture we tried. The SL280 with QT500 hubs, calcium-sulfonate grease, and IP54 sealed coupling guard has handled 5 years of continuous duty with one slider replacement during a planned terminal overhaul. The 4.4 mm misalignment envelope has comfortably absorbed the cumulative thermal-growth profile of the stacker boom.”<\/p>\n<\/p><\/div>\n

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\u2605\u2605\u2605\u2605\u2606<\/p>\n

Iceland \u2014 Geothermal Power Station<\/h4>\n

Used in:<\/em> Cooling-tower fan auxiliary drive on a geothermal-power generation facility.<\/p>\n

Feedback:<\/em> “Continuous outdoor duty in sub-Arctic ambient (-25 \u00b0C winter, +12 \u00b0C summer) required synthetic-grease specification and careful design review. The SL280 has now passed 7 years of continuous duty without any unplanned event. Knock one star only because the initial synthetic-grease selection guidance from the catalogue could be more prominent for extreme-cold service \u2014 engineering had to clarify by separate query during commissioning.”<\/p>\n<\/p><\/div>\n<\/div>\n

Frequently Asked Questions<\/h3>\n
\nWhat is the documented torque reserve factor at this size?<\/summary>\n

Standard SL280 catalogue specification carries a 2.5\u00d7 torque-reserve factor against the host-equipment continuous rating \u2014 i.e., for a 10 000 N\u00b7m continuous duty, the SL280’s actual peak-torque capacity is approximately 25 000 N\u00b7m before any permanent-deformation risk. With the QT500 ductile-iron hub variant this rises to approximately 30 000 N\u00b7m peak. This generous reserve accommodates the routine 1.5\u20132\u00d7 rated-torque shock events typical of large industrial drives.<\/p>\n<\/details>\n

\nHow is the SL280 handled and installed at 94 kg?<\/summary>\n

Lifting and handling at this mass requires hoist or overhead-crane support. Each hub masses ~45 kg, slider plate ~8 kg, with the assembled coupling at 94.3 kg total. Ever-power supplies pre-machined lifting eyelets on the hubs on customer request, and the standard packaging includes installation instructions covering hoist-supported assembly with appropriate sling and shackle hardware. Installation by a competent crew is typically a 90-minute task including precision-shaft positioning.<\/p>\n<\/details>\n

\nWhat is the recommended FMEA framework for the SL280?<\/summary>\n

Ever-power maintains a documented Failure Mode and Effects Analysis for the cross-slider Oldham architecture, available on request. The framework identifies three primary failure modes: slider face wear (gradual, inspectable, plannable replacement), grease degradation (gradual, scheduled-maintenance reversible), and hub keyway shear (rare, prevented entirely by taper-bushed mounting). Each mode is rated for severity, occurrence, and detection per IEC 61882 conventions. The FMEA documentation supports reliability-engineering review and safety-case file integration.<\/p>\n<\/details>\n

\nCan the SL280 be specified for SIL 1 \/ SIL 2 applications?<\/summary>\n

The SL280 itself is a mechanical asset with no electrical components, and does not require independent SIL certification. For deployment in safety-instrumented systems (SIS), the coupling’s documented FMEA, its gradual failure mode, and its predictable maintenance routine support straightforward SIL 1 and SIL 2 integration as part of broader safety-function analysis. Please consult Ever-power engineering for application-specific safety-case documentation requirements.<\/p>\n<\/details>\n

\nWhat is the documented 30-year fatigue endurance margin?<\/summary>\n

For typical industrial duty (60 % rated load, 250 r\/min average, parallel offset below 1.5 mm), the QT500 ductile-iron hub section accumulates fatigue damage at less than 5 % of total endurance over a 30-year service life. This leaves substantial margin against duty-cycle variations and atypical load events. Cast-iron hubs in field-service historically remain dimensionally stable for 25\u201335 years across multiple slider-replacement cycles.<\/p>\n<\/details>\n

Quote SL280 for Critical Industrial Drives<\/h3>\n

For large process-mill, marine main-shaft auxiliary, primary mining-conveyor, and power-station auxiliary installations in the 250\u2013330 kW power class, the SL280 is the senior-engineered specification of choice across continuous-production heavy industrial duty. Browse the wider SL series catalogue<\/a>, read about Ever-power’s critical-asset supply capability<\/a>, or move directly to a B2B enquiry below.<\/p>\n

\n Quote SL280 Now \u2192<\/a>\n<\/p>\n