LAC PKRC55/95 Controlled-Atmosphere Box Furnace with Internal Gas Recirculation

Overview

The LAC PKRC55/95 is a precision-engineered controlled-atmosphere box furnace designed for thermal processing under reproducible, chemically stable gaseous environments. Its core architecture integrates an internal axial recirculation fan that ensures uniform convective heat transfer across the entire working zone—critical for eliminating thermal gradients during annealing, sintering, brazing, and controlled oxidation/reduction treatments. Unlike static atmosphere furnaces, the PKRC series maintains dynamic gas homogeneity through continuous internal circulation, minimizing boundary-layer stagnation and significantly reducing surface oxidation of sensitive alloys, ceramics, and powder metallurgy components. The furnace operates up to 950 °C as standard, with an optional Inconel-lined chamber enabling extended use at 1100 °C. Vacuum compatibility is achieved via standardized G1/2 ports for external pump integration, supporting processes such as vacuum annealing, vacuum hardening, and low-pressure sintering in accordance with ASTM F2628 and ISO 2738 standards.

Key Features

• Forced gas recirculation system with high-efficiency axial fan, delivering consistent atmosphere composition and temperature distribution throughout the chamber volume.
• DIN 17052-1 compliant temperature uniformity (ΔT ≤ 10 °C across usable volume) verified at 950 °C—validated per EN 60068-3-5 for thermal testing equipment.
• Robust dual-zone heating design using high-stability NiCr resistance wire elements, independently monitored by K-type thermocouples and isolated via zero-crossing solid-state relays.
• Integrated safety architecture: independent mechanical overtemperature limiter (setpoint adjustable), pressure-relief valve (4–6 mbar burst threshold), door position interlock, and redundant current monitoring.
• Modular controller platform: standard HT205 (LAN-enabled, 30×15-step programmable ramp-soak profiles) with optional HT200 upgrade (30×25 steps, USB/LAN, real-time parameter logging).
• G1/2 water-cooling interface and configurable forced-air cooling ducts support controlled cooldown rates down to 0.5 °C/min—essential for stress-relief annealing and phase-controlled transformations.

Sample Compatibility & Compliance

The PKRC55/95 accommodates cylindrical samples up to Ø272 mm × 410 mm depth, optimized for batch processing of sintered metal compacts, ceramic green bodies, thin-film substrates, and precision-machined tooling inserts. Its sealed chamber—equipped with fluorosilicone door gasketing and leak-tight flanged gas inlets—achieves leakage rates <1×10⁻³ mbar·L/s under inert purge, meeting requirements for oxygen-sensitive applications per ISO 8502-9. The furnace conforms to CE Directive 2014/35/EU (Low Voltage) and 2014/30/EU (EMC), and its control software architecture supports FDA 21 CFR Part 11-compliant electronic records when paired with HTMonit monitoring suite—including user access controls, audit trails, and electronic signature capability. Optional calibration packages include traceable measurement loop verification per ISO/IEC 17025.

Software & Data Management

The HT205 and HT200 controllers feature embedded Ethernet (TCP/IP) and serial (RS232/EIA-485) interfaces for seamless integration into laboratory automation networks. HTMonit—a Windows-based universal monitoring application—enables real-time visualization of chamber temperature, gas flow status, pressure, and power consumption, with configurable alarm thresholds and automated CSV export. All process data are timestamped and stored with metadata (operator ID, program name, chamber ID), satisfying GLP documentation requirements. Optional firmware upgrades support Modbus TCP protocol for SCADA-level interoperability. Data integrity is preserved via non-volatile memory with battery-backed clock and cyclic redundancy checksum validation on all logged entries.

Applications

• Vacuum-assisted sintering of stainless steel and tungsten carbide powders (ASTM B964)
• Controlled-atmosphere annealing of silicon wafers and Ni-based superalloys
• Chlorination treatment of rare-earth magnets and transition-metal oxides
• Hydrogen-reducing atmospheres for copper oxide reduction and catalyst activation
• Low-oxygen brazing of aluminum heat exchangers and titanium aerospace components
• Thermal cycling validation per IEC 60068-2-14 for electronic packaging reliability testing

FAQ

Can the PKRC55/95 operate under full vacuum without modification?
No. It requires connection to an external vacuum pump via the standard G1/2 port; no integrated pumping system is included.
Is the furnace suitable for chlorine gas applications?
Yes—when equipped with optional chlorination-grade seals and Inconel chamber lining; standard configuration supports Ar, N₂, and forming gas only.
What is the maximum sample mass the chamber can accommodate without compromising temperature uniformity?
Uniformity compliance is maintained for loads up to 12 kg when distributed centrally; heavier or asymmetric loads require custom thermal mapping per DIN EN 60068-3-5.
Does the HT205 controller support remote firmware updates over LAN?
Firmware updates must be performed locally via USB stick; remote update capability is available only with HT200 + HTMonit v3.2 or later.
Are calibration certificates provided with the furnace?
A factory-as-built temperature uniformity report is included; accredited calibration (ISO/IEC 17025) is available as an optional service with NIST-traceable reference sensors.