Replacing the Axial Pre-optics Window

The axial pre-optics window protects the internal components from particulates and fumes from the plasma.

Always turn off your instrument before attempting to the window and do not operate the instrument while the window is removed.

There are three steps to the procedure:

• Removing the axial pre-optics window assembly
• Replacing the axial pre-optics window
• Installing the axial pre-optics window assembly

Figure 1. Torch compartment

Where:

1. Cone	4. Snout	7. Torch
2. Axial pre-optics window assembly	5. Radial pre-optics window assembly
3. Cone thumb screws	6. RF coil

To remove the axial pre-optics window assembly:

1. Turn off the ICP-OES instrument.

Hot Surface The torch compartment and components in it become extremely hot during instrument operation and remain hot for some time after the instrument has been switched off. Allow the torch compartment to cool for at least five minutes before attempting to remove any component. Use heat-resistant gloves.

Do not hit the RF coil when performing this procedure.

2. Remove the torch and snout. See Figure 1.
3. Undo the three thumb screws holding the cone in place.
4. Pull the cone down out of the assembly.
5. Gently pull down on the axial window assembly.
   
   
   Figure 2. Axial pre-optics window assembly removal
6. Tilt the top of the assembly towards the back and then slide to the right to remove it from the torch compartment.
7. Check the axial pre-optics window for contamination. Replace or clean if needed.

To replace the axial pre-optics window:

Figure 3. Axial pre-optics window assembly

Where:

1. Axial pre-optics window

2. Axial window nut

1. Unscrew the axial window nut from the assembly.
2. Remove the axial pre-optics window from the assembly. It should slide out easily.

Always wear gloves when replacing the window. Hold the window by the edges only. Oils from your hands will damage the window.

5. Insert the new or cleaned axial pre-optics window into the assembly.
6. Screw in the axial window nut into the assembly.

To install the axial pre-optics window assembly:

1. Tilt the top of the axial pre-optics window assembly towards the back of the instrument and then slide it up into the housing.

Do not hit the RF coil.

You must replace the axial pre-optics window assembly before fitting the cone. The cone will not fit properly if the axial pre-optics window assembly is not installed.

Figure 4. Cone inserted without the axial pre-optics window assembly

2. Align the holes in the assembly with the screws and then push the assembly in.

Figure 5. Align axial pre-optics with screws

3. Install the cone onto the assembly.
4. Tighten the three thumb screws firmly by hand.

If the thumbs crews holding the cone in place are not tightened firmly enough the cooling properties of the cone may be affected.