Malvern Mastersizer 3000 Manual

Maintenanc e
89
Cell windows — replacing and re-assembling
The procedures below detail how to fit a new cell window into the cell seal and reinsert it
into the wet cell plate/holder. Take the same precautions when reusing the existing cell
window after its cleaned; protect the cleaned window with lens tissue where necessary.
Lubricate the seals before fitting
With new seals you may find that the circular section of the seal is difficult to press down
into the recess of the cover plate or main cell body. This will make it very hard to get the
circular section to sit flush with the flat surface of the metalwork, and you may find the
long loops of the seal are held away from the metal surface where they join the circular
section.
If this is the case, you will need to lubricate the seal to make it easier to fit. The choice of
lubricant will depend on the tightness of the seals and the dispersant to be used.
l
Water. Use water if you will be using water as your dispersant, or if the dis-
persant is readily miscible with water (such as ethanol).
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Other dispersant. If you are using an oil or a dispersant that is immiscible with
water (such as white spirit) try to use the dispersant itself.
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Soluble lubricant. If the seals are very tight, or the dispersant is unsuitable for use
as a lubricant (it may be volatile or hazardous) you will need to use a soluble lub-
ricant. However, the lubricant must be cleaned away from the inner faces of the
seal before you can make a measurement with the cell.
After you have assembled the cell window into the seal as described in the Re-assembling
the Cell Windows section, wet a cotton bud with the lubricant. Wipe it around the inside
of the window recess in the cover plate or main cell body. Fit the window and seal imme-
diately, so the lubricant does not have any time to dry out. With particularly tight seals
you may have to wipe around the inside and outside surfaces of the circular section of the
seal as well.
Re-assembling the cell windows
1. Take a wet cell seal and place its sealing face onto a flat surface. Use a clean lens
tissue under the cell seal.
2.
Without touching the window faces, remove a cell window from its protective

Malvern Mastersizer 3000 Specifications

General

Measurement principle	Laser diffraction
Blue laser wavelength	470 nm
Sample dispersion options	Wet and dry dispersion
Data acquisition rate	10 kHz
Particle size range	0.01 to 3500 microns
Laser type	He-Ne and solid state
Accuracy	Better than 1%
Repeatability	Better than 0.5%
Technology	Mie and Fraunhofer theories
Sample dispersion units	Hydro MV, Hydro LV, Aero S
Optical model	Mie theory
Power requirements	100-240 V, 50/60 Hz
Detector arrangement	Log-spaced array