ASME B31.3 Process Piping Saudi Arabia

Code Overview

What Is ASME B31.3? — Scope and Saudi Arabia Application

ASME B31.3 Process Piping is the ASME Boiler and Pressure Vessel Code for process piping. It establishes minimum safety requirements for the design, materials, fabrication, assembly, examination, inspection, and testing of piping. In Saudi Arabia, ASME B31.3 is not optional — SAES-L-132 (Saudi Aramco Engineering Standard for Process Piping) mandates it as the base code for all process piping on Aramco project sites.

ASME B31.3 Applies To

Petroleum refineries — crude distillation, hydrotreating, FCCU
Chemical and petrochemical plants — SABIC, Sadara, Yanbu facilities
NGL processing plants — fractionation, gas sweetening
Pharmaceutical manufacturing
All Saudi Aramco process piping under SAES-L-132

FS Target: B31.3 in One Sentence

ASME B31.3 defines the minimum safety requirements for design, materials, fabrication, examination, inspection, and testing of process piping in refineries, chemical plants, and NGL facilities — and is the mandatory base code for all Saudi Aramco process piping under SAES-L-132.

ASME B31.3 vs B31.1 — Quick Comparison

Code	Scope
B31.3	Process piping — refineries, chemical plants, NGL
B31.1	Power piping — boilers, turbines, steam
B31.4	Liquid pipelines — crude, NGL, liquid slurry
B31.8	Gas transmission and distribution pipelines

In Summary

ASME B31.3 Process Piping is the mandatory base design code for all process piping in Saudi Aramco refineries, NGL plants, and chemical facilities, applied through SAES-L-132 which layers additional Saudi-specific requirements on top. Under B31.3, all piping components must meet dimensional standards — pipe to ASME B36.10M, butt-weld fittings to ASME B16.9, and flanges to ASME B16.5 — and carry EN 10204 Type 3.1 mill test certificates traceable to the original heat number. SAEP-347 Annex 4 cross-references B31.3 pipe grades to specific material numbers: ASTM A106 Gr.B seamless is P-001, ASTM A333 Gr.6 low-temperature pipe is P-011, and ASTM A335 P22 alloy pipe is P-022. Gulf Union Ozone stocks carbon steel, Cr-Mo alloy, and stainless steel pipe in Jeddah, all in sizes 1 inch to 24 inch NPS, each supplied with EN 10204 3.1 MTCs and the correct SAEP-347 Annex 4 material number reference on the packing list and delivery documentation.

Fluid Service Categories

Fluid Categories Under ASME B31.3 — Saudi Aramco Project Applications

Category	Hazard Level	Typical Saudi Application	Inspection Class	Key B31.3 Design Note
Category D	Non-hazardous	Utilities: steam, cooling water, instrument air, plant air	Normal — simplest permitted	≤ 1.03 MPa (150 psi); -29°C to 186°C
Normal	General industrial	Crude oil transfer, process condensate, SAES-L-132 standard lines	Normal (5% random RT)	Standard design rules; all common materials permitted
Category M	Highly toxic or flammable	H₂S sour gas, LPG, HF acid, chlorine, ammonia lines	Increased — SAES-L-132 §6 mandates for Cat M	Zero-leakage joints required; restricted materials list per SAES-L-132
High-Pressure	Above ASME B16.5 Class 2500	Wellhead gathering lines, high-pressure gas injection	Severe — 100% RT per Chapter IX	Separate Chapter IX design rules; more conservative safety factors

RT = Radiographic Testing. Examination percentages shown are B31.3 minimums; SAES-L-132 applies additional requirements for Category M and sour service lines. Confirm examination class with your project engineering specification.

Under ASME B31.3, Saudi Aramco projects classify all process fluids into four service categories that determine inspection requirements and examination scope. Category D service (non-flammable, non-toxic, design pressure ≤1,035 kPa and temperature ≥29°C) requires only visual examination. Normal Fluid Service is the baseline for most Aramco hydrocarbon process piping, requiring 5% random weld examination. Category M service (highly toxic fluids where a single exposure could be fatal) requires 100% examination plus additional leak detection provisions. High Pressure service (above Class 2500 ASME B16.5 pressure-temperature rating) requires 100% examination and special material documentation. SAES-L-132 adds a mandatory layer: all Aramco projects require minimum 10% random radiographic examination on butt welds regardless of fluid category, with 100% radiography required for high-consequence lines including crude oil, gas, H₂S sour, and LNG service.

B31.3 Permitted Materials

ASME B31.3 Permitted Materials — Pipe, Fittings, and Flanges

Service	Pipe Grade	Fitting Grade	Flange Grade	Temp Range	GUO Stock
General Process (CS)	ASTM A106 Gr.B / API 5L Gr.B	ASTM A234 WPB	ASTM A105	-29°C to 427°C	Ex-stock 1"–24"
Low-Temperature CS	ASTM A333 Gr.6	ASTM A420 WPL6	ASTM A350 LF2	-46°C to 345°C	Ex-stock 1"–16"
Alloy Steel Cr-Mo (P11)	ASTM A335 P11 / P12	ASTM A234 WP11	ASTM A182 F11	-29°C to 593°C	Ex-stock 1"–12"
Alloy Steel Cr-Mo (P22)	ASTM A335 P22	ASTM A234 WP22	ASTM A182 F22	-29°C to 649°C	Ex-stock 1"–12"
Stainless 304L / 316L	ASTM A312 TP304L / TP316L	ASTM A403 WP304L / WP316L	ASTM A182 F304L / F316L	-196°C to 816°C	Ex-stock 1"–24"
Duplex 2205	ASTM A790 UNS S31803	ASTM A815 WP2205	ASTM A182 F51	-29°C to 300°C	Ex-stock 1"–12"

All above grades are covered under SAES-L-132 §4. Gulf Union Ozone stocks all common sizes from 1" to 24" NB from Jeddah warehouse, with EN 10204 3.1 mill test certificates and SAEP-347 material number references supplied with every order. Alloy and duplex grades may require lead time for large-bore sizes — contact us before submitting BOM.

Saudi Aramco Stricter Requirements

SAES-L-132 and ASME B31.3 — Saudi Aramco Process Piping Requirements

SAES-L-132 does not replace ASME B31.3 — it layers Saudi Aramco-specific requirements on top. Where SAES-L-132 is stricter than B31.3, SAES-L-132 governs. Five key areas where Saudi Aramco goes beyond the base B31.3 requirements:

1

Impact Testing Below 0°C — Mandatory

ASME B31.3 allows exemptions from impact testing for many common grades. SAES-L-132 removes most exemptions — all CS pipe operating below 0°C must pass Charpy V-notch impact testing per paragraph 323.2.2 (sub-zero applications).

2

PWHT Threshold — 19mm Wall CS

Post Weld Heat Treatment (PWHT) is mandatory for carbon steel pipe butt welds with wall thickness ≥ 19mm. B31.3 states the same threshold (19.1mm) but leaves some interpretation; SAES-L-132 states it explicitly and without exemption for CS in pressure service.

3

SAEP-347 Approved Materials — Category M Lines

Valve body, trim, and piping materials on Category M (toxic/flammable) lines must come from the SAEP-347 approved materials list. This links B31.3 fluid category classification directly to SAEP-347 procurement — the engineer must specify the correct SAEP-347 material number in the BOM.

4

PMI Required on All Alloy Piping

Positive Material Identification (PMI) is required for all alloy piping components (P11, P22, P91, stainless, duplex) before installation. ASME B31.3 recommends PMI but does not mandate it. SAES-L-132 makes it a construction requirement — PMI reports must be filed with the inspection authority.

5

Weld Joint Quality Factor E = 1.0

SAES-L-132 requires a weld joint quality factor E = 1.0 for all pressure piping — this means seamless pipe or SAW (submerged arc welded) pipe with 100% radiographic examination. ERW pipe with reduced E factors is not permitted on Aramco process lines without specific engineering approval.

Gulf Union Ozone SAES-L-132 Compliance

All pipe supplied by Gulf Union Ozone for SAES-L-132 Category M and Normal service lines is seamless (E = 1.0), sourced from SAEP-347 approved mills, and supplied with EN 10204 3.1 MTCs including heat number, chemical composition, mechanical properties, and hydrostatic test results.

SAES-L-132 imposes five requirements on ASME B31.3 process piping stricter than the base code. First, alloy steel pipe (1¼Cr-½Mo and 2¼Cr-1Mo grades) and all pipe above 1 inch NPS for Category M service requires Charpy impact testing at −20°C with minimum 27 J absorbed energy. Second, post-weld heat treatment thresholds are tightened: A106 Gr.B pipe requires PWHT above 19 mm wall thickness. Third, materials in SAEP-347 Category M must pass Positive Material Identification per SAEP-1142 before final acceptance. Fourth, all butt welds on primary process lines must achieve weld efficiency factor E=1.0, requiring 100% radiography or TOFD/PAUT ultrasonic examination. Fifth, all pipe must be supplied with EN 10204 3.1 certificates traceable to the originating mill heat number. Gulf Union Ozone stocks ASME B31.3 and SAES-L-132 compliant pipe grades with pre-verified EN 10204 3.1 documentation ready for Aramco project delivery.

Material Number Cross-Reference

SAEP-347 Materials Compatible with ASME B31.3

When procuring ASME B31.3 compliant piping for Saudi Aramco projects, use SAEP-347 material numbers to ensure traceability and approved mill sourcing. The table below cross-references common B31.3 grades to their SAEP-347 Annex material numbers.

B31.3 Grade	Product	SAEP-347 Annex	Material No.	Notes
A106 Gr.B (SMLS)	Pipe	Annex 4	P-001	Standard CS seamless — most common on Aramco
A106 Gr.B (ERW)	Pipe	Annex 4	P-002	ERW only on non-Category-M with engineering note
A333 Gr.6 (SMLS)	Pipe	Annex 4	P-011	Low-temp CS; mandatory impact test certified
A335 P11 (SMLS)	Pipe	Annex 4	P-021	1¼Cr-½Mo; high-temp alloy
A335 P22 (SMLS)	Pipe	Annex 4	P-022	2¼Cr-1Mo; hydrocracker, reformer service
A312 TP316L (SMLS)	Pipe	Annex 4	P-051	316L SS seamless; NACE MR0175 restrictions apply
A234 WPB	BW Fittings	Annex 5	F-025	CS seamless butt-weld fittings; ASME B16.9
A105	Flanges	Annex 6	FL-001	CS forged flange; ASME B16.5 Class 150–2500

SAEP-347 material numbers shown are indicative. Always verify against the current SAEP-347 revision issued by Saudi Aramco. Gulf Union Ozone can supply certified documentation referencing all SAEP-347 Annex 4 (pipes), Annex 5 (fittings), and Annex 6 (flanges) material numbers.

Examination & Inspection

ASME B31.3 Inspection Classes for Saudi Aramco Projects

Examination Type	B31.3 % Minimum	Saudi Aramco Requirement	When Applied
Normal Examination	5% random RT on groove welds	Standard — applies to Category D and non-critical Normal lines	Utility piping, non-hazardous service
Increased Examination	10% random RT on groove welds	SAES-L-132 §6 mandates for Category M and sour service	H₂S sour gas, LPG, toxic and flammable process lines
Severe (100%) Examination	100% RT / UT on all welds	High-Pressure (Chapter IX) and specific SAES-L-132 critical services	Wellhead lines, HP injection, critical pressure piping

RT = Radiographic Testing; UT = Ultrasonic Testing. Saudi Aramco projects typically specify Increased examination class for Category M and High-Pressure service under SAES-L-132 §6. Confirm with your project's Piping Class specification or IFC drawing package before procurement.

Order B31.3 Pipe

Request ASME B31.3 / SAES-L-132 Compliant Pipe — Jeddah Ex-Stock

RFQ Sample — B31.3 CS Process Pipe

Material: ASTM A106 Gr.B seamless
Size: 8" NPS (DN 200)
Schedule: Sch 40
Length: 6m random / cut to length
SAEP-347: P-001
Service: Normal — SAES-L-132 process
Weld joint factor: E = 1.0 (seamless)
MTC: EN 10204 3.1 required
PWHT: Not required (wall < 19mm)
Qty: 150m / 25 lengths

Request B31.3 Pipe Quote

7 Items to Include in a B31.3 Pipe RFQ

ASTM grade and seamless / ERW requirement
NPS (or DN) and wall thickness or schedule
Length (random or cut-to-length)
B31.3 fluid service category (D / Normal / M / HP)
SAEP-347 material number (from BOM)
SAES-L-132 examination class required
MTC type: EN 10204 3.1 (or 3.2 if TPI required)

Typical Lead Times from Jeddah

A106 Gr.B SMLS: Same day — 2 days (1"–12") / 5 days (14"–24")
A333 Gr.6: 2–5 business days (1"–12")
A335 P11/P22: 3–7 business days (up to 12")
A312 TP304L/316L: Same day — 3 days (1"–12")
A790 Duplex 2205: 5–10 business days (1"–8")

FAQ

ASME B31.3 Process Piping — Questions Answered

What is the difference between ASME B31.3 and ASME B31.1?

ASME B31.3 covers process piping used in petroleum refineries, chemical plants, NGL processing, and pharmaceutical facilities. ASME B31.1 covers power piping for boilers, steam generation, and nuclear applications. Saudi Aramco projects specify ASME B31.3 as the base design code for all process lines, implemented via SAES-L-132 (Process Piping), which adds Saudi-specific requirements on top of the B31.3 base including mandatory impact testing below 0°C, PMI on all alloy piping, and stricter heat treatment thresholds.

Does ASME B31.3 apply to Saudi Aramco projects?

Yes — SAES-L-132 mandates ASME B31.3 as the base design code for all process piping on Saudi Aramco project sites. SAES-L-132 does not replace B31.3; it adds Saudi Aramco-specific requirements on top. EPC contractors on Saudi Aramco, SABIC, Sadara, and NEOM projects must satisfy both ASME B31.3 and SAES-L-132 simultaneously. Where the two standards conflict, the stricter requirement governs. Gulf Union Ozone supplies piping certified to both B31.3 and SAES-L-132 with full SAEP-347 material number documentation.

What pipe material grades are B31.3 and SAEP-347 compliant?

The most common B31.3 / SAEP-347 compliant pipe grades for Saudi Aramco projects are: ASTM A106 Gr.B seamless (general CS process, SAEP-347 P-001), ASTM A333 Gr.6 (low-temperature CS service down to -46°C, SAEP-347 P-011), ASTM A335 P11 and P22 (Cr-Mo alloy for high-temperature service up to 649°C), ASTM A312 TP304L and TP316L (austenitic stainless for corrosive service), and ASTM A790 UNS S31803 (duplex 2205 for chloride-containing sour service). Gulf Union Ozone stocks all of these in Jeddah in sizes 1" to 24" NPS with EN 10204 3.1 MTCs and SAEP-347 material number documentation.

Related Resources

Source ASME B31.3 / SAES-L-132 Compliant Pipe from Jeddah

Include ASTM grade, NPS, schedule, length, SAEP-347 material number, service category, and MTC requirement. We confirm stock availability, SAES-L-132 compliance status, and pricing within 4 business hours. ASTM A106 Gr.B seamless in common schedules ships same-day from Jeddah.

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ASME B31.3 Process Piping for Saudi Aramco Projects — Materials, Compliance & Supplier Guide