Positive Displacement Flowmeters

IPE Engineering Practice IPE-EP-12-1-15

Document number: IPE-EP-12-1-15 · Section: 12 — Instruments and Controls

SCOPE

This Practice presents detailed requirements for Positive Displacement flowmeters. All positive displacement flowmeters shall be supplied in strict accordance with EP 12–1–15DS, this practice, and other referenced Practices and Industry standards.
Any deviation from this Practice must be approved by the procedure described in EP 1–1–3.
A revision bar indicates all changes made to this Revision.

2.0 REFERENCES

The following codes and standards shall be considered as part of this Practice. All documents shall be the latest editions in force on the date of issuance of this Practice.

STANDARDS AND PUBLICATIONS

IPE Engineering Practices
EP 1–1–3 Deviations to IPE Engineering Practices EP 5–2–2 Flanges, Gaskets and Bolting EP 5–3–1 Valve Design and Selection Criteria EP 12–1–1 Control Systems EP 12–1–2 Supplemental Requirements for Control Systems EP 12–1–15DS Positive Displacement Flowmeters Data Sheet
ASME
B 1.20.1 Pipe Threads General Purpose (Inch)
NEMA
ICS 6 Enclosures for Industrials Controls and Systems
NFPA
70 National Electrical Code

DEFINITIONS

Contractor - Company or business that agrees to furnish materials or perform specified services at a specified price and/or rate to the Owner.
Inspector - A Inflection Point Engineering, LLC appointed engineer or inspector.
Manufacturer - The recipient of a direct or indirect purchase order for materials and/or equipment. In this context, a direct order is one issued to a manufacturer by a contractor or the Owner. An indirect order is one issued to a manufacturer by a vendor (recipient of a direct order) for materials, fabricated components, or subassemblies.
Owner - Inflection Point Engineering, LLC
Owner’s Engineer - A Inflection Point Engineering, LLC appointed engineer.

Purchaser - The party placing a direct purchase order. The purchaser is the Owner’s designated representative.

GENERAL

The equipment shall consist of a measuring element and associated transmitter/electronics.
The pressure temperature rating of the measuring element shall be equivalent to Class 600 ANSI flange rating minimum for elements having threaded or socketweld connections, and to the specified flange for elements having flanged connections.
The dimensions and ratings of flanges shall conform to EP 5–2–2.
All threaded connections shall be tapered and shall conform to ASME B1.2.1.
Design and materials not specified shall be in accordance with the manufacturer’s standards suitable for the operating and design conditions specified on the Data Sheet.
All electrical conduit connections shall be internally threaded 1/2 inch NPT.
Linearity: 0.5% maximum deviation from the average sensitivity (K) across the linear range.
Repeatability: 0.1% maximum deviation from the actual flow rate over the linear flow range
Valves, strainers, air eliminators, and other piping components shall meet the requirements of EP 5–3–1.

5.0 INSTRUMENT ENCLOSURES

Positive displacement flowmeters shall be listed by Factory Mutual (FM) or Underwriters Laboratory (UL) for the National Electrical Code (NEC) area classification Class 1, Groups B, C, and D, Division 2. In addition, enclosures shall be weatherproof NEMA type 4.

6.0 CALIBRATION

Transmitters shall be factory calibrated for the range specified on the Data Sheet.

7.0 INSTRUCTIONS FOR DATA SHEET

The following numbers correspond to the line numbers on the Data Sheet.

1.	Show meter tag number
2.	Refers to process service or application
3.	Give line number or process area
4.	Type of rotating element: disc, piston, vane, helical, rotor, etc
5.	Specify line size and schedule
6.	Specify size and style on connections, such as 1 in NPT, 2 in 300 #RF
7.	Pressure and temperature design rating required
8.	Nominal flow range is obtained from manufacturer’s data. This usually defines the linear range
	of the selected meter
9.	Specify smallest totalized unit: tenth of gal, lbs, bbls.

10.	Specify enclosure electrical classification: Class 1, Group D., Div 2
11.	Specify power supply
12–18	Specify materials of construction or write in ”MFR. STD.”
19.	Specify type of coupling
20.
21.	Specify register type: horizontal, vertical, dial, print, etc
22.	Specify number of figures: 6 digit, 0-99,999, etc
23.	If required, write in type
24.	Number of figures or maximum quantity.
25.	Specify ”yes” if set-stop is required to operate shutoff valve, etc
27–35	Specify fluid data as indicated
36.	Specify ”yes” if shut-off valves is required.
37.	Specify ”yes” if switch is required. Two switches are required for 2-stage control.
38.	Specify ”yes/no”
39.	Specify if transmitter is required and type: pulse, etc
40.	Specify output in pulse per gallon, 4-20 mA, etc.
41.	Specify ”yes/no”
42.	Specify strainer size and mesh size. Request vendors recommendation if not known.
46–51	Fill in after selection is made.

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