Page 36 - Parker - The Handbook of Hydraulic Filtration

Appendix

SAMPLING
PROCEDURE
Obtaining a fluid sample for particle A. In the Tank Sampling
counts and/or analysis involves impor- l. Operate the system for
tant steps to make sure you are getting at least 1/2 hour.
a representative sample. Often 2. Use a small hand-held vacuum
erroneous sampling procedures will pump bottle thief or “basting
disguise the true nature of system syringe” to extract sample. Insert
cleanliness levels. Use one of the sampling device into the tank to one
following methods to obtain a half of the fluid height. You will prob-
representative system sample. ably have to weight the end of the
sampling tube. Your objective is to
I. For systems with a obtain a sample in the middle por-
sampling valve
tion of the tank. Avoid the top or bot-
A. Operate system for a least 1/2 hour. tom of the tank. Do not let the
B. With the system operating, open the syringe or tubing came in contact
sample valve allowing 200 ml to 500 ml with the side of the tank.
(7 to 16 ounces) of fluid to flush the
3. Put extracted fluid into an
sampling port. (The sample valve
approved, pre-cleaned sample bottle
design should provide turbulent flow
as described in the sampling valve
through the sampling port.)
method above.
C. Using a wide mouth, pre-cleaned
4. Cap immediately.
sampling bottle, remove the bottle
5. Tag with information as described
cap and place in the stream of flow
in sampling valve method.
from the sampling valve. Do NOT
“rinse” out the bottle with initial
B. In-Line Sampling
sample. Do not fill the bottle more
1. Operate the system for at
than one inch from the top.
least 1/2 hour.
D. Close the sample bottle immediate-
2. Locate a suitable valve in the
ly. Next, close the sampling valve.
(Make prior provision to “catch” the system where turbulent flow can be
fluid while removing the bottle from obtained (ball valve is preferred). If
the stream.) no such valve exists, locate a fitting
E. Tag the sample bottle with perti- which can be easily opened to pro-
nent data: include date, machine vide turbulent flow (tee or elbow).
number, fluid supplier, fluid number 3. Flush the valve or fitting sample
code, fluid type, and time elapsed point with a filtered solvent. Open
since last sample (if any). valve or fitting and allow adequate
flushing. (Take care to allow for this
II. Systems without a step. Direct sample back to tank or
sampling valve into a large container. It is not

There are two locations to obtain a necessary to discard this fluid.)
sample in a system without a sampling
valve: in-tank and in the line. The
procedure for both follows:

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