ATMOSPHERIC CHEMICAL VAPOR CLAD SYSTEM

ATMOSPHERIC CHEMICAL VAPOR CLAD SYSTEM

ASI/SILICA Machinery’s Dual Spindle system provides optimum control over chemical vapor deposition in an atmospheric environment. The system can be used for the silica soot deposition process in the manufacturing of either pure fused silica or the overcladding of OVD, MCVD, PCVD, or VAD core preforms. Each machine can make 2 preforms at a time. The system is made of highly engineered components and is designed to operate reliably with repeatable results. The Dual Spindle System is available as an upgrade to already existing ACVD18 models or as a new stand alone machine.

CHEMICAL DELIVERY SYSTEM

The chemical delivery system continuously delivers SiCl4, 02, and H2 to generate silica. The system is helium leak tested to a level of 1×10-8 std cc/sec per fitting.

GAS DELIVERY SYSTEM

The gas delivery system is made of electro-polished 316 stainless steel components, assembled in a class 10 clean room environment and equipped with a sub-micron filters to insure the highest level of purity. The system incorporates a series of mass flow controllers and air operated diaphragm valves. Upon completion, the system is helium leak tested to a level of 1×10-8 std cc/sec.

THE DEPOSITION CHAMBER

The system has a specially designed reaction chamber, made of stainless steel and lined with corrosion resistant materials for protection. The reaction chamber is equipped with a pre-filter, Hepa filter and variable speed blower, to maintain a clean-air environment within the chamber. A flow sensor within the cabinet assures proper ex-haust flow during operation. The work area is illuminated by a pair of fluorescent lamps.

PROCESS CONTROL

All the process parameters are monitored and complete process control is achieved using an industrialized personal computer. Run data,including work piece diameter, is displayed on the screen for easy monitoring and automatically stored on the hard drive for process analysis and trouble-shooting.

SAFETY FEATURES

The system is equipped with hydrogen detectors, safety interlocks, flash arrestors and excess pressure and temperature alarms that will shut the system down in the event of a malfunction. The system’s features also include explosion proof fluorescent lights and gas monitors.

SYSTEM SPECIFICATIONS

Soot Preforms per Machine Run 2
Nominal Max Soot Preform Length(drawable) 2100mm
Nominal Max Soot Preform Weight(per spindle) 60kg approximate
Nominal Soot Preform Diameter at Max Length
(soot preform density 0.5g/cc, weight 50kg)
230-300 mm approximate
(equivalent to 118-150 mm glass preform).
Nominal Max Preform Size (per spindle) 1650km to 2000km
Deposition Rate Average (per spindle) 50 grams/minute approximate
Deposition Rate Average (per machine) 100 grams/minute approximate
Approximate Machine Dimensions 516cm x 275cm x 220cm
Approximate Footprint Requirement 700cm x 500cm x 365cm
(Including Clearances)
Chemicals Used Methane or Natural Gas or H2, O2, N2, SiCl4
Electrical Requirements 230 VAC, 10kW (Estimated)
Cleanroom Requirements Class 10,000 or better. Preferably Class 1,000
(supplied by customer)