© 2019 Department of Petroleum Resources. All rights reserved Department of Petroleum Resources (DPR) PROCEDURE GUIDE

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2.5.5 Operation of Automatic Sampling System
2.5.5.1 Before the commencement of loading, the desired frequency of sample grab shall be
calculated for the batch in accordance with the procedure set out in ASTM D4177.
Minimum sample frequency (bbl/grab) = 0.0001233D2
D – nominal pipe diameter (mm)
While No. of grabs for the parcel shall be deduced from the relationship
No. of grabs =
𝑷𝒂𝒓𝒄𝒆𝒍 𝑺𝒊𝒛𝒆
𝑴𝒊𝒏𝒊𝒎𝒖𝒎 𝑺𝒂𝒎𝒑𝒍𝒆 𝑭𝒓𝒆𝒒𝒖𝒆𝒏𝒄𝒚

2.5.5.2 The sampler shall be allowed to operate continuously throughout the loading
operation and shall not be removed until fluid flow has ceased in the pipeline after the
shutdown of loading pumps, for production purposes the auto sampler or any suitable
device approved by the Director Petroleum Resources shall be allowed to run for 24 hours
(8am-8am). Thereafter, the sample in the receiver shall be transferred to the laboratory for
quality analysis either in the receiver, if it is the removable type, or in a secondary receiver,
which shall be a well labeled container made of suitable material after proper mixing within
the primary receiver to ensure that the original homogeneity is maintained.

2.5.5.3 The following records should be made after each loading operation:
i.
Sample reference number.
ii.
Identification of shipment or transfer.
iii.
Petroleum and petroleum product type.
iv.
Date and time of commencement of sampling.
v.
Date and time of completion of sampling.
vi.
Nominated expected flow rate.
vii.
Maximum expected flow rate.
viii.
Sample grab size.
ix.
Sample rate.
x.
Calculated sample volume.

Time
Total
Quantity
of
Petroleum
and
petroleum
product
Transferred
Target sample
Quantity
Actual
sample
Quantity
%
of
Total
Petroleum
and
petroleum product
Transferred
% of Total
sample
Collected