Graphite Furnace Maintenance

Graphite Furnace Maintenance

Objectives • Outline a suitable protocol for routine maintenance covering: – Furnace workhead – Furnace autosampler – Instrument body • Maintain instrument performance

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GTA Maintenance • • • • •

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Graphite Tube Electrodes Shroud Windows Chimney

Maintenance Log

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Daily Inspection Schedule • Exhaust system • Utilities – Water – Gas • Instrument case • Furnace compartment • Instrument windows

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Check Exhaust

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Clean Spills

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Daily Inspection of the Workhead • Graphite Tube • Injection Port/Chimney • Windows • Electrodes • Shroud

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Examine the Electrodes

Chips

Plugged gas holes

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Clean the Electrodes

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Check Shroud

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Clean End Windows

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Clean Chimney

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Daily Inspection of the Autosampler • Check capillary • Check tubing leading to/from syringe • Clean up any spills • Check/refill rinse solution • Empty waste container

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Dirty Capillary

Rinse with Aqua Regia

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Trimming Capillary When Required

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PSD Maintenance • Check syringe • Check capillary tubing leading to/from syringe • Clean up spills

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Bubble in Syringe

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Tapping Plunger on Bench Top

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Components Required for Maintenance • Items required for cleaning – Methanol solution (10-20%) – Cotton buds or Q-tips – Lens tissue – Scalpel knife

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Periodic Maintenance • Check water recirculator – Check flow rate – Check water level • Gas delivery system – Regulators working properly – Leaks (hoses, fittings, etc...) • Windows – HCL & compartment – GTA – Workhead compartment • Change electrodes 21

Check Utilities Gas Delivery Pressure • Argon 30 - 40 psi Water Supply • Required flow rate 1.5 - 2.0 L/min • Maximum of 30 psi • Maximum temperature 40 oC • Recommended 20 - 25 oC

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Clean Windows YES, YOU MUST DO THE WINDOWS!

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Summary • Discussed benefits of routine maintenance • Reviewed items to be inspected daily – Workhead – PSD • Items for periodic maintenance

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