MODIFIED CHEMICAL VAPOR DEPOSITION (MCVD)

Project gallery

MCVD Enclosure Layering Illustration

Customer Need

The customer needed to accurately control the relative movements of fiber optic pre-form and torch while regulating the precise delivery of several gases simultaneously during the MCVD processHelp.

Custom Systems and Controls was asked to design and build an automated system to effectively perform with the following design specifications:

  • Existing footprint
  • Gas flow delivery minimum 100psi
  • Time restrictions
  • Stay within budget

    • Solution

    CSC designed and fabricated controls for the proprietary lathe that contained a Oxygen/Hydrogen torch, controls for gas delivery system (gases included fluorine, erbium, terbium), controls for a laser micrometer that is linked to back pressure in order to control the diameter of the preform which is also linked to the chuck rotation speed in order to compensate for wobble (sag), and fabricated the full enclosure with the required safety features.

    Some features of the project include:

  • custom control software w/ GUI
  • software for HMI
  • customized operator controls
  • full enclosure with safety features and custom fume hood

    • System Components

    Mitsubishi PLC
    Mitsubishi/Beijers HMI’s
    National Instruments LAB Windows
    Festo Pneumatics
    Mitsubishi Servo Motors
    Windows Based Industrial Computer
    irCon Pyrometer
    Keyence Laser Micrometer
    Tylan and Unit mass flow controllers (MFC’s)

    Success

    CSC was able to successfully complete the project for the client on time and on budget. The project was such a success that the client had CSC fabricate 2 additional systems. All 3 systems have been in service for over 12 years and have not required any major repairs.

    In the Modified Chemical Vapor Deposition (MCVD) process, a highly controlled mixture of chemicals is passed through the inside of a rotating glass tube made of pure synthetic SiO2. The pure silica tube is mounted on a lathe equipped with a special heat torch. As the gasses flow inside the tube, they react to the heat by forming solid submicron particles, called "soot," in the vicinity of the heat zone. Once the soot is formed, it is deposited on the inner wall of the tube. As the burner traverses over the deposited soot, the heat transforms these solid white particles into pure, transparent glass, in a process called vitrification. The deposited material will form the core region of the optical fiber.
    Enlarged Layering Illustration
    Enlarged MCVD