Section 5 — Piping

Piping System Line Numbering

IPE Engineering Practice IPE-EP-5-1-5

Document number: IPE-EP-5-1-5 · Section: 5 — Piping

SCOPE

This Practice covers the requirements for identifying service lines on Piping and Instrumentation Flow Diagrams, piping plan and elevation drawings and piping isometric drawings.
Any deviation to this Practice must be approved by the procedure described in EP 1–1–3.
An asterisk (*) indicates that a decision by the Owner or Owner’s Engineer is required.

2.0 REFERENCES

The latest edition of the following publications are referred to herein.

STANDARDS AND PUBLICATIONS

DEFINITIONS

Additional Notes - Designations which identify additional attributes of a piping system, see EP 5–1–1.
Insulation Condition - Designation which identifies attributes of the insulation system:
H–heat conservation
C–cold insulation
PP–personal protection
ET–electric tracing
ST–steam tracing
Line Number Sequence - A number assigned to each line starting with Number 1 for each fluid symbol.
Line Service Symbol - The fluid service in each line is identified by a letter symbol. One, two, or three letters may be used for a fluid symbol, see Section 5.0 of this Practice.
Owner’s Engineer - A Inflection Point Engineering, LLC appointed engineer.
Pipe Size - More than one pipe size may be required for a line. Each line size is shown along with its physical data. Normally, only one line of a Line Rating Sheet is used for each line size listed. However, for additions, a second size can be included if an unused space is not available. There is one exception - pipe sizes in material classes which require wall calculations must have each size listed independently.

Piping Material Specification - Specific designation based on pressure class, piping material, service, and temperature. Permissible designations are described in EP 5–2–3. Normally only one material class is assigned for piping covered by a single line number. This requires a piping system to carry two line numbers when a class–break occurs. However, two classes may be included under one number where there is a limited amount of pipe or piping components in the second class.
Unit Identifier - An abbreviated string of Alpha–Numeric characters used to identify the Plant unit or area to which the line number corresponds.

COMPOSITE LINE NUMBER

(*)Unless otherwise specified by the Owner’s Engineer, the following piping system line numbers shall be used:

8” - 891 - P - 21 - BAAA1 - I - ST

PIPE SIZE

UNIT IDENTIFIER LINE SERVICE

LINE NUMBER SEQUENCE

PIPE MATERIAL SPECIFICATION PER EP 5-2-3

INSULATION IDENTIFIER ADDITIONAL NOTES PER EP 5-1-1

(*)Unless otherwise specified by the Owner’s Engineer, the line numbering scheme detailed in Figure 1 shall be used.

5.0 LINE SERVICE SYMBOL

The Line Service Symbols in Table 1 shall be used as part of the Composite Line Number described in Section 4.0. Use of Line Service Symbols not included in Table 1 requires approval of the Owner’s Engineer.

6.0 TABLES

TABLE 1

LINE SERVICE SYMBOL CROSS–REFERENCE

LINE SERVICE	IPE
Additives	CF
Air	A
Ammonia	NH
Atmospheric Vent	V
Bleed Air	BA
Blowdown	BD
Boiler Feedwater	BFW
Catalyst	CT
Caustic	CA
Chemical Feed	CHF
Clean Condensate	C
Closed Drain	CD
Cooling Water Return	CWR
Cooling Water Supply	CWS
Cutting Water	CW
Decoking	DK
Drain	DR
Exhaust	E
Exhaust Steam	ES
Fire Water	FW
Flare Header	FH
Flare Vent	VF
Flushing Oil	FLO
Foam Systems	FMS
Fuel Gas	FG
Fuel Oil	FO
Gland Oil	GO
Heavy Fuel Oil	HFO
High Pressure Boiler Feedwater	HBFW
High Pressure Condensate	HPC
High Pressure Steam (410PSI)	HS
Hydraulic Oil	HO
Hydrogen	H
Hydrogen Sulfide	H2S

TABLE 1

LINE SERVICE SYMBOL CROSS–REFERENCE (CONTINUED)

LINE SERVICE	IPE
Instrument Air	IA
Lean Amine	ML
Light Fuel Oil	LFO
Low Pressure Boiler Feedwater	LBFW
Low Pressure Condensate	LPC
Low Pressure Saturated Steam (30 / 60 PSI)	LS
Lube Oil	LO
Medium Pressure Condensate	MPC
Medium Pressure Steam ( 150 PSI )	MS
Nitrogen	N
Oily Water Sewer	OWS
Pilot Gas	PG
Plant Air	PA
Potable Water	DW
Process– H2 in sour service	PHS
Process– Hydrocarbon Liq & Vap	P
Process– Sour	PS
Process Water	PW
Rich Amine	MR
Seal Oil	SO
Slop Oil	SLO
Snuffing Steam	SX
Sour Water	SW
Spent Caustic	SCA
Sulfur	S
Tempered Water	WT
Wash Oil	WO
Waste Gas	WG
Waste Water	WSW

7.0 FIGURES

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