Design, Fabrication, Supply, Installation and Commissioning of High temperature graphite resistance heating furnace

Amount

Horizontally mounted double walled water cooled cylindrical chamber (inner dia of 1200 mm and length of 1500 mm, inner wall thickness of 12 mm and outer wall of 6 mm) made out of non-magnetic type stainless steel 304L or better with annular gap of 15mm having guides. Dished ends, front door, ports for evacuation, pump-out during process, thermocouples, electrical feedthroughs, gas feedthroughs, PRV, capacitance monometers, inert gas backfill, viewport, furnace calibration etc. Fabrication including welding, inspection etc., as per ASME code SEC VIII Div I/ASME CODE SEC IX.

Graphite Furnace : High quality silicon resistant graphite heating elements of M/s. Schunk/Mersen/SGL etc., make grade of strip type arranged in a suitable fashion with graphite hardware’s and connected to electrical feedthroughs with a maximum Design temperature of ≥1850C and continuous operating temperature of 1800C under vacuum/inert atmosphere. Temperature uniformity of ±5C in the effective zone after temperature stabilisation at 600C and Heating rate of 20C per minute/max. at different soaking temperature is achieved from ambient to ≥1800C with 30kg load. Actual hot zone (Inside heater size/heating element ID) : 450 mm (W) x 450 mm (H) x 900 mm (D)

Furnace Insulation: High quality silicon resistant rigid graphite board insulation (from Shunk/FMI/or equivalent) with impervious carbon fibre composites (CFC) on hot face. Total insulation thickness can be 150mm or more (to ensure that the skin temperature of the furnace will not exceed 50-60C). Cut-outs are provided in hot zone for visual observation, for introducing thermocouples/radiation pyrometer, electrical feedthroughs and these cut-outs are suitably covered with insulation shield to avoid radiation heat losses. Insulation is to be supported with perforated stainless steel sheet with suitable stiffeners,

Graphite Retort: Graphite retort/Muffle : Cuboid-graphite retort with an outer dimension/area of 370 mm (W) x 370 mm (H) x 500 mm (D) and inner dimensions 320 mm(W) x 320 mm(H) x 450 mm (D) with necessary support bars inside.

Charge loading Hearth : Hearth plate (supported on graphite support rods, which is further supported on SS supports welded to the bottom portion of the chamber) made out of silicon resistant high density graphite having a loading area of 320 mm (W) x 450 mm (D) x 20 mm thick for loading charge directly

Inert gas filling system: Gas inlet supply manifold fabricated out of SS with the provision to connect 4 Ar and 4 Nitrogen with necessary regulators, isolation valves, pressure gauge, PRVs etc. Appropriate gas lines built using Swagelok components (sandvik tube, valves, needle valves, union, connectors, etc.,) connecting the supply manifold and the furnace through solenoid operated valve, pressure switch, pre-set needle valve, pressure gauge, Mass Flow Controller, etc., to back fill and to ensure flow during the operation. Digital pressure sensor to sense the chamber pressure and give the signal to solenoid valve to close and mechanical pressure relief valve to release the excess argon/nitrogen pressure

Furnace Power: Furnace heating system consists of heavy duty 390-440 V AC, 50 Hz, 3 phase supply mains operated at 275 kW (or better) transformer, whose primary is controlled through phase angle thyristor power controller of M/S. Eurotherm make providing continuously variable output for entire operating range and secondary is coupled to heating elements. This is coupled to the programmable PID controller (Eurotherm make, 2604 or better) to control the power requirement of the furnace automatically as per the programmed temperature profiles without deviation. Provision to measure and display the current and voltage of furnace zone heating elements by providing suitable volt and current meters through current transformer. Secondary is monitored by good quality analog Ammeter/ Voltmeter. Three phase input through phase angled thyristor power control with fuse protection and current limits. Fused, remotely operated furnace heater power supply contactor having capability for opening and closing hot zone power circuit as well as power transformer protection. Isolation transformer for all controls and instruments. Miscellaneous items such as motor starter, MPCBs, circuit breakers, fuses etc., as required. Main circuit breaker for all controls and power circuits, voltmeters and ammeters. Water cooled power cables/ Bus Bar connecting the transformer to the furnace power feedthroughs.

Vacuum Pumping System : A high speed vacuum pumping system consisting of M/s Edwards make (or equivalent) rotary/roots based system with necessary electro pneumatic valves mounted on frame out of SHS to achieve an ultimate vacuum level of 1x10-3 mbar in about 10-15 minutes in clean, empty chamber, and maintaining vacuum of 1x10-3 mbar can be achieved/demonstrated with suitable ramp rates for temperature and several soaks using the complete cycle to ≥1800 deg C Details as per Chapter-4

Leak Rate: Chamber and its sub assembles weldments are leak tested using helium mass spectrometer leak detector to an individual leak rate of 3 X10-9 mBar litres/sec and the same is demonstrated. In clean, cold, empty chamber after thorough de-gassing a global leak rate of 1 X10-3 mBar litres/sec is achieved in the furnace chamber by pressure raise method with valve off condition

Vacuum Measurements: I. Ms Edwards make (or equivalent make) vacuum gauge controller with two pirani sensors to measure rough vacuum in the range of 1000 mbar to 10-4 mbar. Capacitance monometer of reputed make like Ms MKS or equivalent having measuring range of 0.1 mbar to 1000 mbar with controller II. Capacitance monometer of reputed make like Ms MKS or equivalent having measuring range of 10 mbar to 10-3 mbar with controller III. Pressure Relief Valves with appropriate set pressure on the chamber to avoid excess pressure raise inside the chamber with both electronic and mechanical relief valves. IV. Manual Vent Valve: A manually operated vent valve to admit the argon gas into the chamber to open the chamber in the absence of power

Condensate trap: A condensate trap with the series of SS dust filters and disposable paper filters provided in between the furnace chamber and the vacuum pump to condense the silicon/other vapours and mechanically trapped fine dust particle arising from the process. This water cooled condenser cools the hot gases coming out from the retort when the condenser is circulated with water.

Temperature measurement and Control Philosophy: I. Digital temperature programmer and control: Microprocessor based PID Controller from M/S. Eurotherm (2604 or better). II. Thermocouples: Two No’s of reputed make Tungsten-5% Rhenium vs. Tungsten-26% Rhenium thermocouple (Type C) with Hafnia insulation in Molybdenum sheath, out of which one is for temperature measurement and control and the other one is for Safety temperature control. III. Safety Temperature Controller: Digital temperature controller of Eurotherm make 3216 with a relay output interlocked with furnace power supply in the event of any malfunctioning of programmable PID temperature controller/control thermocouple.

Instrumentation: I. A programmable logic controller (PLC): A PLC controller of reputed make like Ms GE or Eurotherm or Allen Bradley, Schneider, Omron etc for automation of vacuum cycle, temperature cycle, to have inter locks with manual over riding facility. II. Industrial PC with touch screen and SCADA software: An integrated 21” industrial PC with touch screen facility with GE (or equivalent) supervisory control and data acquisition software (SCADA) with on-line control facility. This is for complete operation of the furnace in auto mode and to acquire various process data as and when required. The features of the SCADA software as detailed in Chatper-4

UPS: A reputed make UPS, single phase supply 3 kVA rating with back up support for 1-hour time for the computer and control instrumentation including PLC/PC and all input data meters/gauges. Appropriate instrumentation is provided to sense main incoming power supply.

AUXILIARY SYSTEMS: I. CLOSED LOOP WATER COOLING SYSTEM: Closed loop water cooling system is provided for cooling, Furnace chamber, electrodes, cables etc., All the electrodes have independent water cooling lines. All water-cooled power cables have individual water flow lines for easy maintenance. Details as per Chapter-4

Air Compressor: An air compressor (AIR COMPRESSOR OIL FREE AIR NOT EXCEEDING 1ppm) of required capacity to produce air at a pressure of 10 kg/cm2 for all pneumatic valves with required FLR unit is provide

Documents provided at PDR: Details as per Chapter-4

CD comprising of licensed version all Software (life time validity) and Functional description drawing (As built/As installed and As commissioned)

Computer suitable for the software (supervisory PC): DELL, New OptiPlex 7000 Tower processor, 12th Generation Intel®️ Core™️ i5-12400 (6 Cores/18MB/12T/2.5GHz to 4.4GHz/65W), Windows 10 Pro (Windows 11 Pro license included), English (Dell Technologies recommends Windows 11 Pro for business) videocard, Intel®️ Integrated Graphics memory, 16 GB, 1 x 16 GB, DDR5, harddrive M.2 2230 500GB PCIe NVMe Class 35 Solid State Drive (EM) fallbackcolor 260 W internal power supply unit (PSU), 85% Efficient, 80 Plus Bronze ot better NB This computer is customized to enable to load SCADA, PLC programs etc., and operate the furnace

Sub-Total

Less: Discount (if any)

Sub-Total:Net Ex-Works Price

Add: Packing & Forwarding charges (if any)

Add: Transportation Charges (if any)

Add: Insurance charges (from warehouse-to-warehouse) (if any)

Total (A):

Installation & Commissioning charges (if any)

Training charges (if any)

Total (B):

Bank Charges, if any

Total (C):

AMC Charges for 1st year, If any

AMC Charges for 2nd year, If any

AMC Charges for 3rd year, If any

HIND HIGH VACUUM CO. PVT LTD