Nabertherm L 9/11/SKM Corrosion-Resistant Laboratory Muffle Furnace
| Brand | Nabertherm |
|---|---|
| Origin | Germany |
| Model | L 9/11/SKM |
| Type | Box-Type Muffle Furnace |
| Max Temperature | 1100 °C |
| Temperature Uniformity | ±1 °C |
| Max Power | 3.0 kW |
| Heating Time to Max Temp | 90 min |
| Heating Method | Resistance Wire (Embedded in Ceramic Chamber) |
| Internal Dimensions | 230 × 240 × 170 mm (W × D × H) |
| Chamber Volume | 9 L |
| External Dimensions | 490 × 505 × 580 mm (W × D × H) |
| Weight | 90 kg |
| Electrical Supply | 1-phase, 230 V, 50 Hz |
Overview
The Nabertherm L 9/11/SKM is a laboratory-grade corrosion-resistant muffle furnace engineered for thermal processing in chemically aggressive environments—such as ashing of halogenated polymers, sulfur-containing samples, or routine analysis involving acidic or alkaline volatiles. Its defining feature is a fully enclosed, monolithic ceramic muffle chamber with integrated heating elements on all four vertical walls. This design eliminates direct exposure of metallic heating wires to corrosive atmospheres while ensuring radial heat distribution and high spatial temperature uniformity (±1 °C at 1100 °C). Unlike conventional furnaces with exposed coil windings, the L 9/11/SKM employs a robust alumina-silica ceramic muffle that resists degradation from Cl⁻, SO₂, HF, and other reactive species commonly generated during sample decomposition. The furnace body is constructed from brushed stainless steel (V2A / 1.4301), and the door assembly uses high-density ceramic fiber insulation—ensuring low surface temperatures and minimal particulate shedding during ashing protocols.
Key Features
- Ceramic muffle with embedded resistance heating elements on all four sidewalls—eliminates corrosion pathways to heating conductors
- Optimized thermal architecture delivering ±1 °C temperature stability and uniformity across the full 9 L working volume at 1100 °C
- Two door configurations available: front-opening (L version) for easy sample loading; top-hinged (LT version) for operator safety and reduced radiant exposure
- Adjustable air inlet on door and rear-mounted exhaust port—enabling controlled atmosphere management during volatile residue removal
- Low-noise operation via solid-state relay (SSR) switching and optimized thermal mass distribution
- Integrated overtemperature protection per EN 60519-2 Class 2—mechanical limit thermostat cuts power independently of controller if setpoint is exceeded
- Standard NTLog basic data logging via USB flash drive—records time-stamped temperature, setpoint, and status events compliant with GLP traceability requirements
Sample Compatibility & Compliance
The L 9/11/SKM is routinely deployed in accredited environmental, pharmaceutical, and materials testing laboratories where ISO/IEC 17025, USP , ASTM D5630, and DIN 51718 ashing procedures are enforced. Its inert ceramic chamber ensures compatibility with chloride-rich biomass, PVC-based plastics, coal, activated carbon, and catalyst residues without cross-contamination or muffle degradation. Optional gas purge fittings support nitrogen, argon, or forming gas (5% H₂/95% N₂) blanketing—critical for redox-sensitive ashing (e.g., ASTM E1357). All electrical and thermal safety systems conform to IEC 61000-6-4 (EMC), IEC 61000-6-2 (immunity), and CE marking requirements under the EU Machinery Directive 2006/42/EC.
Software & Data Management
While the standard controller operates via intuitive rotary encoder and LCD interface, optional VCD (Virtual Control Device) software enables remote monitoring, multi-furnace synchronization, and audit-trail-compliant process recording. VCD supports 21 CFR Part 11–ready user authentication, electronic signatures, and immutable event logs—including parameter changes, alarm triggers, and manual overrides. Data export is available in CSV and PDF formats compatible with LIMS integration. For routine GLP workflows, NTLog provides sufficient traceability: timestamps, temperature profiles, and cycle completion flags are saved directly to FAT32-formatted USB media without requiring external PCs.
Applications
- Gravimetric ash content determination per ISO 1171, ASTM D3174, and EN 14778
- Preparation of inorganic residues for ICP-OES/MS analysis following EPA Method 3050B
- Thermal cleaning of crucibles, boats, and quartzware exposed to corrosive fluxes
- Controlled pyrolysis of halogenated flame retardants prior to halogen speciation
- Calibration and validation of thermocouples and reference materials in metrology labs
- Heat treatment of ceramic precursors and metal oxide catalysts under inert or reducing atmospheres
FAQ
Is the ceramic muffle replaceable as a field-service component?
Yes—the muffle is a modular, bolted-in assembly designed for straightforward replacement without recalibration. Nabertherm supplies certified replacement muffles with batch-specific dimensional and thermal certification.
Can the furnace operate continuously at 1100 °C?
Rated for continuous operation up to 1100 °C; however, sustained use above 1000 °C requires periodic verification of muffle integrity and thermocouple drift per ISO/IEC 17025 internal calibration schedules.
What protective gas connections are supported?
Standard 6 mm OD stainless steel compression fitting for inert or reactive gas supply; optional catalytic afterburner or active fume extraction can be integrated via rear exhaust port.
Does the controller support programmable ramp-soak profiles?
Yes—the standard controller includes up to 16 segments with independent rate (°C/min), soak time, and hold conditions; VCD software extends this to 99-segment profiles with conditional branching.
Is third-party calibration documentation included?
Factory calibration certificate (traceable to PTB) is provided with each unit; UKAS-accredited calibration services are available upon request with documented uncertainty budgets.
