Description
SL150 Heavy-Industrial Cross-Slider Oldham Coupling — 150 mm Cast-Iron Hub for Pulp, Paper and Bulk-Material Drives
The SL150 industrial Oldham coupling brings the cross-slider family into the upper-middle band of heavy industrial duty. With a 1 250 N·m rated torque, 150 mm hub OD, 55–60 mm bore range, and 250 r/min permissible speed, the SL150 transmits 25–33 kW of continuous mechanical power. This is the duty class of pulp-and-paper roll drives, sugar-mill mill-house feed shafts, large bulk-material conveyor head drives, primary-process mixer outputs, and the larger pump drives in process-plant utility systems. The coupling at this size is no longer a small commodity item — it is a deliberately specified asset whose service history will likely span the entire installed life of the surrounding equipment.
The SL150 is also a transition point in the SL family. At smaller sizes, the cast-iron architecture competes mainly against elastomer-spider and grid couplings. At the SL150 size and above, it begins to compete against gear couplings and disc-pack couplings of substantially higher unit cost. The SL150 holds its ground in this competitive space on three engineering points: zero backlash that gear couplings cannot match without precision tooth grinding, a parallel-misalignment envelope (2.2 mm) substantially wider than any disc-pack coupling can deliver, and an installation procedure that any maintenance technician can execute without specialised training. These remain decisive factors in OEM and plant-engineering selection.
Specifications
| Parameter | Value |
|---|---|
| Model | SL150 |
| Nominal Torque (Tn) | 1 250 N·m |
| Permissible Speed (n) | 250 r/min |
| Bore Range (d) | 55 – 60 mm |
| Outside Diameter (D) | 150 mm |
| Hub Bore Diameter (D₁) | 95 mm |
| Overall Length (L) | 112 mm |
| Slider Plate Thickness (H) | 19 mm |
| Slider Clearance (S) | 0.5 mm |
| Moment of Inertia | 0.14 kg·m² |
| Mass | 15.5 kg |
| Radial Misalignment (Δy) | 2.2 mm |
| Angular Misalignment (Δα) | 0.5° |
| Axial Misalignment (Δx) | 2.0 mm |
| Shaft Engagement | Keyway + setscrew |
| Lubrication | Grease (re-pack annually) |
Materials
HT250 / QT500 Hubs
Catalogue specification is HT250 grey cast iron with stress-relief annealing prior to machining. QT500-7 ductile-iron variant is documented for paper-mill, pulp-mill, and shock-load applications where the higher fracture toughness pays back through extended fatigue life. Hub-mass distribution is engineered to minimise reflected inertia at the host motor.
Hardened Steel Slider
45-steel cross-slider with induction-hardened sliding faces to HRC 45–55. 40Cr alloy slider variant offered for reversal duty and abrasive ambient (paper-mill stock, abrasive bulk solids). For applications requiring electrical isolation between motor and load (e.g., insulated test stands, instrumentation drives), a bronze CuSn10 slider is available with appropriate torque de-rating.
Standard Industrial Mounting
H7-reamed bore with parallel keyway to GB/T 1096. M14 set-screw for axial location. For very high-torque or high-cycle applications, taper-bushed mounting via standard locking-assembly families (e.g., RINGFEDER 7012, Trantorque locknuts) is documented as a custom-build option that eliminates the keyway-shear failure mode entirely.
Selection Considerations at 25–33 kW
At the SL150’s power level, an unplanned coupling failure typically takes out an entire production line. The selection question is therefore not just about peak performance — it is about predictability of failure modes and serviceability of wear parts. In this engineering frame, the SL150 has two structural advantages over competing flexible-coupling families. First, the failure mode is gradual polymer-free wear of an inspectable metallic slider, not the catastrophic-event failure mode of an elastomer, spring-pack, or precision-flexure component. Plant maintenance can predict slider replacement intervals from inspection data, schedule the work during planned shutdowns, and avoid all unplanned downtime.
Second, the wear part itself is field-serviceable in less than one shift. With both hubs remaining keyed to their shafts, the maintenance crew lifts the slider out, fits a new one, repacks the grease, and the equipment is back on line. No precision laser-alignment exercise is required — the cross-slider geometry self-aligns the new component. By contrast, a flexible-disc coupling at this rating requires a precision alignment exercise after every disc-pack replacement, easily extending the maintenance window to a full shift or more on a typical production install.
Industry Applications
Pulp & Paper Roll Drives
Drying-roll and calender auxiliary drives in tissue, kraft, and newsprint production lines. Misalignment tolerance absorbs the thermal growth between roll-cold and roll-hot states.
Large Bulk-Material Conveyors
Head and intermediate drive couplings on 800–1200 mm wide bulk conveyors. Shock-load absorption protects motor bearings during inrush loading events.
Wine & Spirits Production
Press-screw and pump drives on large-scale wine, spirits, and fermentation facilities. QT500 hub variant tolerates the chemical-process ambient of acidified must.
Cement-Plant Auxiliaries
Pre-heater feed, kiln-feed conveyor, and clinker-cooler drives on cement-production lines. Dust-tolerant grease maintenance routine suits established cement-plant maintenance practice.
Aquatic Centre & Pool Pumps
Filtration and circulation pump drives on commercial aquatic centres and large pool facilities. QT500 hub variant resists chlorinated-water spray ambient.
Grain-Elevator Bucket Drives
Head-pulley drives on commercial grain elevators and feed-storage facilities. The 2.2 mm parallel allowance forgives the tall-frame deflection typical of elevator installations.
Why Choose Ever-power
Quality & Compliance
SL150 production runs under ISO 9001:2015. Cast-iron melt traceability with chemical-composition certification per heat. RoHS, REACH, and CE conformity declarations standard. For pulp-and-paper customers, supplementary documentation covering wash-out resistance of the slider lubrication system is available. For cement-plant customers, dust-class certifications are issued with the QT500 hub variant.
Customisation
Catalogue bore range 55–60 mm; oversized variants up to 65 mm and undersized down to 50 mm produced under engineering review. Imperial-bore variants (2-1/8″, 2-1/4″, 2-3/8″) supported for North American markets. QT500 ductile-iron hub upgrade is documented and lead-time-stable for high-shock and corrosive deployments.
Aftermarket & Logistics
SL150 slider plates stocked under part SL150-SLIDER; 40Cr alloy variant available within 1 week. Mass per coupling is 15.5 kg; sea-freight standard, air-freight available for emergency builds. English-speaking engineering desk responds within 24 hours.
Customer Reviews & Case Studies
★★★★★
Nigeria — Palm-Oil Processing Facility
Used in: Press-cake conveyor drive at the digester-press transition of a mid-scale palm-oil mill.
Feedback: “Press-cake handling is a hot, oily, abrasive environment. The SL150 has now passed 5 years in continuous duty with two slider replacements during planned shutdowns — total combined downtime of 90 minutes over the entire 5-year history. Equipment supervisor describes this as the most reliable coupling in the entire mill.”
★★★★★
Slovakia — Paper-Mill Modernisation
Used in: Calender auxiliary drives across a tissue-paper machine rebuild.
Feedback: “Specified the SL150 as a replacement for the original gear couplings on the calender drives. Three years on, total coupling-related downtime has been zero — versus an average of 12 hours per year on the original gear-coupling fleet. Acquisition cost premium was paid back in the first 9 months of operation through downtime avoidance alone.”
★★★★☆
Slovenia — Hydropower Plant Auxiliary
Used in: Trash-rake drive coupling on a 5 MW run-of-river hydropower plant intake.
Feedback: “Intake-rake duty includes debris-impact events that fatigue most flexible couplings. The SL150 with QT500 hub upgrade has handled this for 7 years without slider replacement — well exceeded our 5-year expected service interval. Knock one star only because we found the QT500 upgrade documentation could be more prominent in the catalogue — easy to miss as an option.”
Frequently Asked Questions
How does the SL150 compare to a gear coupling at the same rating?
Gear couplings at 1 250 N·m offer marginally higher peak-torque capability but typically introduce 0.1–0.3° of angular backlash that the SL150 eliminates entirely. Gear couplings also require precision shaft alignment within 0.15 mm parallel for predictable tooth-wear, versus the SL150’s 2.2 mm tolerance. Lifecycle cost favours the SL150 in nearly all installations except where extreme peak-torque density is the dominant selection criterion.
What is the expected service life of the SL150 hubs?
In service data, HT250 cast-iron hubs on the SL150 typically remain in service for 25+ years before any dimensional issue emerges — substantially longer than typical host-equipment lifecycles. Hubs are therefore effectively “install once, forget” components. The slider is the wear part, with typical 6–8 year replacement intervals under standard duty.
Can the SL150 handle hydropower or wind-pitch service?
Yes for hydropower auxiliary drives (trash-rake, gate-actuator, governor-aux). For wind-turbine pitch-drive applications the SL150 is somewhat undersized; please consult engineering with the specific torque-and-misalignment requirements — typically a larger SL family member (SL170 / SL190) is the appropriate match for wind-turbine pitch service.
Is the SL150 included in your standard maintenance training?
Yes — the SL150 is covered in our generic SL-family training module, which covers installation, grease selection and repack, slider inspection criteria, and slider replacement procedure. Training is available as PDF, short-form video, and remote video-conference delivery for OEM partners.
Are larger custom-bore variants supported?
Catalogue bore range is 55–60 mm. Engineering can release oversized variants up to 65 mm (with hub-section verification), and undersized bores down to 50 mm (with set-screw clamping-force verification). Larger requests are typically better served by stepping up to the SL170 family member.
Quote SL150 for Heavy-Process Drives
For pulp-and-paper, palm-oil, cement, large-conveyor, and hydropower-auxiliary applications, the SL150 is one of the most-installed mid-range cast-iron Oldham couplings on the market. Explore the wider SL coupling catalogue, learn about Ever-power’s heavy-industrial supply capability, or proceed to enquiry below.
