The IPS2050-P-S3 is the paddle with flat holes, stainless steel in the IPS2050 overhead stirrer accessory line — sold separately for use on the OS-20L (IPS2050-20 / -20-E) and OS-40L (IPS2050-40 / -40-E) overhead stirrer chassis. The flat-holes paddle geometry produces mixed axial / radial flow with high local turbulence — the right impeller for higher-viscosity formulation mixing, paste-class semi-solid agitation, and workflows where the propeller-class impellers (-S1, -S2) would slip in viscous medium without producing useful flow.
Key Specifications
| SKU | IPS2050-P-S3 |
| Type | Paddle with flat holes, stainless steel |
| Flow pattern | Mixed axial / radial — high local turbulence |
| Material | Stainless steel (general-purpose chemistry compatibility) |
| Compatible chassis | IPS2050-20 / -20-E (OS-20L) and IPS2050-40 / -40-E (OS-40L) overhead stirrers |
| Best fit chassis | OS-40L (IPS2050-40 / -40-E) — higher torque (60 Ncm) handles higher-viscosity workflows where the paddle is most useful |
| Mounting | Feed-through chuck on chassis — tool-less tightening / loosening |
| Family sister SKUs | IPS2050-P-S1 (one-line propeller), IPS2050-P-S2 (centrifugal impeller), IPS2050-P-S4 (4-arm — default included) |
| Teflon equivalent | IPS2050-P-T3 (paddle w/flat holes Teflon — aggressive-solvent compatibility) |
Why a Paddle with Flat Holes — Mixed-Flow Turbulence Selection
The paddle-with-flat-holes geometry delivers larger swept area per revolution than propeller-class impellers, generating higher local turbulence as fluid moves through the holes. The flat-holes design reduces drag versus a solid paddle while preserving the high-coverage flow pattern.
Pick the paddle with flat holes (IPS2050-P-S3) when:
- Workflow involves higher-viscosity formulations (>1,000 mPa·s) where propeller-class impellers slip in the medium
- Paste-class semi-solid mixing where a 4-arm or one-line propeller would not produce useful flow
- Cosmetic / personal-care formulation (creams, lotions, gels) at viscosities above the 1,000 mPa·s threshold
- Pharmaceutical semi-solid prep (ointments, creams) at pilot-batch scale
- Food-science viscous suspension (sauces, dressings, viscous emulsions)
Pair preferentially with the OS-40L (IPS2050-40 / -40-E) — the 60 Ncm torque and 50,000 mPa·s viscosity ceiling fully exploit the paddle's higher-viscosity capability. The OS-20L (40 Ncm, 10,000 mPa·s ceiling) can drive the paddle at the lower end of its envelope.
Stainless Family Flow-Pattern Comparison
| SKU | Geometry | Flow pattern | Best viscosity |
| IPS2050-P-S1 | One-line | Axial | Low (<1,000 mPa·s) |
| IPS2050-P-S2 | Centrifugal | Radial | Low–medium |
| IPS2050-P-S3 (this product) | Paddle w/flat holes | Mixed turbulent | Medium–high (1,000–50,000 mPa·s) |
| IPS2050-P-S4 | 4-arm | Axial-radial | Low–medium (general-purpose) |
Stainless vs Teflon Material Decision
For higher-viscosity formulation work that includes aggressive solvents (DMSO, DMF, halogenated solvents) or high-acid / high-base chemistry, step to the IPS2050-P-T3 Teflon equivalent — same flow pattern, chemical-resistant material.
Application Profile
High-viscosity pharmaceutical formulation. Cream, ointment, and gel mixing at viscosities up to 50,000 mPa·s on the OS-40L chassis.
Cosmetic and personal-care semi-solid mixing. Lotion, cream, and emulsion mixing in development and pilot-scale batches.
Food-science viscous emulsion prep. Sauce, dressing, and condiment R&D at the 5–40 L pilot scale.
Industrial slurry and paste prep. Process-development workflows where higher-viscosity slurries or pastes need the paddle's high-coverage mixing.
Pharmaceutical excipient suspension. Resuspension of high-mass solids (clay, calcium carbonate, microcrystalline cellulose) in liquid carrier.
Ordering & Configuration
Pair with chassis (recommend OS-40L). Confirm OS-40L (IPS2050-40 / -40-E) inventory at order — the paddle is most effective on the higher-torque chassis.
Pair with appropriate impeller mix per protocol. Labs running mixed low-and-high-viscosity workflows benefit from inventorying both propeller-class (-S1 / -S2) and paddle-class (-S3) impellers.
Confirm at quote: chassis pairing, sample-chemistry compatibility (stainless vs Teflon), workflow viscosity range, and lead time.
Warranty: Per Benchmark Industrial standard accessory terms — confirm at quote.
IPS2050 impeller selection — viscosity-axis decision:
- IPS2050-P-S1 — One-line propeller, low-viscosity axial flow
- IPS2050-P-S2 — Centrifugal impeller, low-medium-viscosity radial flow
- IPS2050-P-S3 (this product) — Paddle w/flat holes, medium-high-viscosity mixed turbulence — pair with OS-40L chassis
- IPS2050-P-S4 — 4-arm general-purpose (included with chassis)
Pick the paddle for higher-viscosity formulation work; Teflon sister IPS2050-P-T3 covers aggressive-chemistry equivalents.
