Chamber and hot zone
The chamber is loaded from the front and contains hot zone sized 4” diameter x 8” high (102 mm x 203 mm) or 8” diameter by 10” high (203 mm x 254 mm) with a +/- 10°C temperature gradient. The heating element is a 1/2- 1/2 split design allowing the die body to be inserted straight into the zone. The furnace chamber is manufactured from doubled-walled stainless steel welded together and electro-polished for a clean finish and good vacuum integrity.
Three hot zone choices are available: a graphite band element and rigid fibrous graphite insulation pack, a Moly-D rod element and ceramic insulation pack, or a high temperature metal mesh heating element and layered metal shielding. In the hot press configuration, the maximum operating temperature is 2300°C (1650°C with ceramic zone). With the end plug shields supplied to plug the top and bottom hot rod openings, the furnace can be used as a batch/sintering furnace with operation temperatures to 2600°C.
The Post and Platen Press Frame with load train is designed and manufactured to withstand well over 15 tons of force. This Post & Platen Frame is fully adjustable for perfect alignment, unlike some standard welded “H” frames on the market. The load train includes water-cooled stainless steel top and bottom cold rods, and high strength top and bottom hot rods. The top rod has a 4.0″ stroke and the top cold rod is sealed by a static O-Ring on a bellows assembly to provide a high-vacuum rated seal.
The Hydraulic Press Control System includes a 4.0″ stroke hydraulic cylinder, a hydraulic power unit, a pressure gauge, and a load cell to measure and control press force. The pump size and servo valve size are calculated to allow fast jogging speeds for loading and positioning. A slow jog speed for fine-positioning is also provided on our HMI systems. Cylinder positional accuracy will be 0.001″ and press force accuracy of 1 lb (5 N).
Power Supply & controls
Power to the hot zone is supplied by a three phase SCR-controlled power supply, meeting the latest NFPA and NEC codes (CE certification available). The power supply is designed to match the heating element, and is sized to allow for fast ramp rates. The transformer includes multiple taps which can be used when the element and shields are aging but still usable. A set of water-cooled power cables supplies power to the hot zone of the furnace.
Temperature and force control is accomplished either with classic instruments and push buttons, or by means of a SCADA/HMI system. Press force and temperature control programs can be synchronized. The HMI system logs data, provides user security, displays graphs, alarms, and provides an intuitive graphical user interface for full furnace control.
A type “C” sheathed and coated thermocouple is supplied and can be used to measure the furnace temperature up to 2000°C. When operating the furnace to temperatures above 2000°C, control is automatically switched over to a Pyrometer.
Vacuum and Gas System
The basic evacuation system consists of a Rotary Vane mechanical pump, an electro-pneumatic vacuum valve, vacuum gauge controller and a vacuum gauge. This vacuum system will allow for operation in a vacuum environment (10-2 Torr range) An optional 4″ or 6″ diffusion pumping system or a turbo pumping system can be provided as well and can achieve vacuum levels down to 10-6 Torr (diffusion pumping system) and 10-7 Torr range (turbo pumping system).
The basic gas system supplied provides an inert environment for the work samples during the heat and physical testing. The process gas system includes a solenoid-operated inlet valve, a compound gauge (30 P.S.I.G. x 30 in. Hg.), a gas flow meter, and a 2 P.S.I.G. outlet relief valve to maintain positive chamber pressure. Optional partial pressure systems, hydrogen operation, mass flow controllers for gas ratios, and other options are also available.
Water cooling system
The furnace water cooling manifold consists of multiple circuits to adequately cool all the furnace parts and includes a strainer, pressure regulator, pressure gauge, water inlet and outlet manifold, a water flow switch as a visual water flow indicator with a flow interlock to protect the furnace in the event of a water flow failure. This switch turns off power to the hot zone if water flow is below recommended minimum for a certain amount of time. Each part of the furnace is supplied with a separate cooling circuit that can be regulated by independent manual ball valves.
||kVA dependent on max temperature rating, 380-480 V/3/50-60 Hz (other voltages available)
||70 F (20°C) and 50 P.S.I.G. (3.4 bar), required flow dependent on kVA rating.
||Argon, Nitrogen or process gas, 30 L.P.M. @ 50 P.S.I.G.
||60-90 P.S.I.G. (4.1 – 6.2 bar) filtered.