
39
GB
7. Maintenance, cleaning and recalibraon
Weights are made of austenic stainless steel which are enrely stable. They should be
periodically cleaned using a non abrasive method to remove any foreign ma er.
7.4.2 Need for overhaul and re-cer icaon
f
We recommend that the pressure balance be returned to us for overhaul and
re-cer icaon at any me if when used in accordance with instrucons:
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1. The piston does not spin freely.
2. The rate of fall of the piston is appreciably greater than when new and makes use of
the pressure balance di cult.
ffi
3. The weights are damaged.
4. The pressure balance cannot be made to operate sasfactorily due to wear or
damage to pump piping or valves which cannot be recied by the user.
This pressure balance can be used for calibraon of instruments with an expected
accuracy of 1, 0.5 or 0.25 %. Such pressure balances need not be sent back frequently
for overhaul and re-cer icaon and provided they are working well can be trusted for
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many years. Under these circumstances, an interval of ive years might be appropriate
f
between overhauls.
When high accuracy of the pressure balances is required, it should be returned for
overhaul and re-cer icaon more frequently. The actual period will depend on how the
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pressure balance is used. A pressure balance kept in a laboratory and carefully used
might need to be returned every two to ive years. A pressure balance carried from site
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to site and used for calibrang high accuracy gauges or transducers from industrial
process plant or for measuring pressures directly might well need to be returned at
intervals of less than speci ied above.
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The actual period between overhaul and re-cer icaon should be ixed by the user in
f
f
the light of the above comments taking into account the requirements of any inspecon
authority, which might be involved.
7.4.3 Iden icaon of weights
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All weight sets supplied with a pressure balance have allocated, and are marked, with
a weight set number. Addionally, if users wish to ensure that only speci ic weights are
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used with an individual pressure balance or piston and cylinder unit, then the serial
number of the pressure balance, and/or piston-cylinder unit may also be marked on the
main weights. Regre ably due to size of certain weights, not all the above informaon
may be marked.
Manual M
LDW-HK
odel
LR-
Cal
Содержание LDW-HK
Страница 16: ...16 GB 3 Speci ica ons f Side view Dimensions in mm without masses Front view Manual M LDW HK odel LR Cal...
Страница 21: ...21 GB 4 Design and func on G D C F E H J K Sec oned view of screw pump Manual M LDW HK odel LR Cal...
Страница 46: ...46 GB Manual M LDW HK odel LR Cal...
Страница 91: ...91 No zen Notes Anleitung Modell LDW HK Druckwaage Kolbenmanometer LR Cal...