The Z446-750-B15 is a 17-position 15 mL conical tube insert for the Hermle Z446-MP-BUK rectangular bucket on the Z446-750-AC 4-place swing-out rotor (Z446 / Z446-K chassis) — sold as a 2-pack. Each insert holds 17 × 15 mL conical tubes; the 4-bucket rotor configuration takes 2 packs (4 inserts) for full symmetric loading, delivering 68 × 15 mL conical tubes per cycle in swing-out geometry. The B-prefix denotes the rectangular-bucket variant — distinct from the A15R insert (18 × 15 mL on the round bucket Z446-750-BUK at 72/cycle). The rectangular bucket geometry supports specific protocol formats (microplate-direct, certain insert layouts) on the Z446-750 platform.
Key Specifications
| SKU | Z446-750-B15 |
| Type | Tube insert — 17 × 15 mL conical (rectangular bucket) |
| Pack quantity | 2 inserts per SKU (full 4-bucket configuration takes 2 units = 4 inserts) |
| Per-insert capacity | 17 × 15 mL conical tubes |
| Per-cycle throughput (full configuration) | 68 × 15 mL conical per cycle |
| Tube format | 15 mL conical Falcon-style (17 mm OD, 120 mm length) |
| Compatible bucket | Z446-MP-BUK (rectangular bucket on Z446-750-AC swing-out rotor) |
| Compatible rotor | Z446-750-AC (4-place swing-out rotor body) — rectangular bucket variant |
| Compatible chassis | Z446, Z446-K (refrigerated), and -E voltage variants |
| Max. operating speed (with insert + tubes) | Per Z446-MP-BUK spec — 4,000/4,500 rpm at 3,130–3,961 × g maximum (slightly lower RCF than round bucket due to 17.5 cm vs 19.2 cm radius) |
| Max. radius | 17.5 cm (rectangular bucket geometry) |
| Temperature at max speed (refrigerated chassis) | 4 °C |
| Geometry | Swing-out (0–90°) — flat sediment surface |
| List price | $507 (2-pack) |
Round Bucket vs Rectangular Bucket — Geometry Distinction
The Z446-750-AC swing-out rotor accepts two bucket profiles:
| Bucket | Max RCF | Max radius | Loading height | Loading weight |
| Z446-750-BUK (round) | 4,346 × g | 19.2 cm | — | — |
| Z446-MP-BUK (rectangular) | 3,961 × g | 17.5 cm | 80 mm | 640 g |
The rectangular bucket reaches lower max RCF (smaller radius) but supports different load-distribution profiles — useful for microplate-direct workflows (the rectangular bucket accepts standard SBS-format microplates without adapter) and for certain rectangular-shaped inserts. The B15 insert (this SKU) uses the rectangular geometry for its 17-position 15 mL conical layout.
Compatibility & When to Order This SKU
Insert pairing — Z446-MP-BUK rectangular bucket only. Order this SKU when:
- Adding 15 mL conical workflow to a Z446-750-AC + Z446-MP-BUK rectangular-bucket install — order 2 units for full 4-bucket symmetric loading (68 tubes/cycle).
- Mixed microplate / 15 mL workflow consolidation — when the lab uses the rectangular bucket primarily for microplate workflows and the B15 insert adds 15 mL conical capability without requiring a round-bucket swap.
- Cold-chain 15 mL conical clinical-research prep on the Z446-K refrigerated chassis at 4 °C max-speed temperature.
- Replacement inserts if a current set is damaged or worn.
Application Profile
4-bucket symmetric loading. All 4 rectangular buckets must use matching B15 inserts for symmetric balance.
Per-insert symmetric loading. Within each insert, the 17 conical tubes should be balanced symmetrically — pair tubes by mass with the seventeenth position symmetric to the insert's central axis.
Design Architecture
Mixed microplate / 15 mL workflow consolidation — when the lab uses the Z446-MP-BUK rectangular bucket primarily for microplate workflows and the B15 insert adds 15 mL conical capability without round-bucket swap.
Cold-chain 15 mL conical clinical-research prep on the rectangular-bucket platform — patient sample fractionation, aliquot prep at 68 × 15 mL conical per cycle on the cold-chain swing-out chassis.
Cell-culture pellet recovery in 15 mL — pelleting non-adherent cells from 68 parallel 15 mL suspension batches per cycle on the rectangular-bucket platform.
Density-gradient prep in 15 mL — Ficoll, Percoll, sucrose-gradient prep at 68 parallel preps per cycle on the cold-chain swing-out chassis with rectangular-bucket geometry.
Cold-chain protein prep in 15 mL — TCA, ammonium-sulfate, organic-precipitation in 15 mL conical at 68 parallel preps with refrigeration on the rectangular-bucket platform.
Cross-format Z446-K core facilities — labs running both microplate workflows (rectangular bucket direct-fit) and 15 mL conical workflows (this B15 insert) on the same Z446-MP-BUK inventory benefit from workflow flexibility.
Ordering & Configuration
4-bucket symmetric loading. All 4 rectangular buckets must use matching B15 inserts. Mixed-bucket configurations produce mass asymmetry.
Tube cap confirmation. All conical tubes must be securely capped before spinning at 4,500 rpm.
Z446-750-B15 ships as 2 inserts. 15 mL conical tubes are operator-supplied (commodity Falcon / Corning / equivalent formats). The Z446-MP-BUK rectangular bucket is sold separately.
Confirm at quote: bucket pairing (Z446-MP-BUK rectangular bucket in inventory — distinct from the round bucket Z446-750-BUK which uses A15R insert), chassis pairing (Z446 or Z446-K) and power configuration, tube format (15 mL conical Falcon-style), pack count (2 packs for full 4-bucket configuration = 68 tubes/cycle), and lead time.
Warranty: 5-Year Hermle warranty (3 years full + 2 years drivetrain) on the inserts.
Z446-750 15 mL conical workflow paths (Z446-750-AC swing-out rotor):
- Z446-750-B15 (this product) — 17 × 15 mL conical insert on Z446-MP-BUK rectangular bucket (68/cycle, 17.5 cm radius)
- Z446-750-A15R — 18 × 15 mL insert on Z446-750-BUK round bucket (72/cycle, 19.2 cm radius)
Pick B15 when the lab uses the rectangular bucket for mixed microplate / 15 mL workflows; pick A15R for highest 15 mL throughput on the round-bucket platform.
