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

Page 49 of 114

48 | P a g e

1.4 Applicable Standards for Design, Installation, Operation and Maintenance of
Meters
The applicable standards for Design, Installation, Operation and Maintenance of Metering
system shall be American Petroleum Institute Manual of Petroleum Measurement
Standards (API MPMS) Chapters 4, 5, 6, 11, 12 and 13.
1.5 Positive Displacement Meters - PD Meters
1.5.1 Description
This is basically a piece of equipment designed to measure a volume of liquid by separating
it into measured quantities (displaced volume) and counting these quantities. Meters of this
type can only measure in one direction; hence it is impossible to reverse flow through such
meters.
1.5.2 Design and Selection
1.5.2.1 Principle
The design shall be based on the Lease Automatic Custody Transfer System (LACT). The
metering assembly shall therefore generally follow the guideline specified in the API Manual
of Petroleum Measurement Standard Chapter 6 of LACT Systems.
1.5.2.2 Selection Criteria
In selecting the meters, consideration shall be given to the viscosity and density of liquid,
solid contents, expected flow rates and operational conditions.
1.5.3 Operation and Maintenance
Flow rate through the bank shall be maintained at between 60% and 80% of the maximum
name plate capacity of each meter. It shall be more acceptable to shut down some of the
meters in the bank to maintain this optimum flow rate than to operate any of the meters
below the 60% capacity.
1.6 Turbine Meters
1.6.1 Description
This is a flow rate measuring device which works on the principle of a sensing rotor moving
with a tangential velocity which is proportional to the volumetric flow rate. The
corresponding volume of liquid passing through the meter is indicated on a pre-calibrated
readout device. Meters of this type can measure reverse flows but for the purpose of this
guide, no reversal of flow shall be allowed.
1.6.2 Design and Selection
1.6.2.1 These shall generally be carried out in accordance with the procedure outlined in API
Manual of Petroleum Measurement Standards Chapter 5 Section 3 and other
reference standards in section 1.4 above.
1.6.2.2 Adequate consideration shall be given to the required maximum and minimum flow
rates, maximum operating pressure and temperature as well as solid particles in the
liquid and the liquid properties.
1.6.2.3 Turbine meters shall not be considered for use at flow rates less than 1,500 barrels
per hour because of the short span of linearity of such meters in this flow regime.
However, meters shall be selected such that they operate always within the linear
portion of their characteristic curves.