Walk through almost any process plant and you will find an NPS 6 line in carbon steel on the firewater ring, chrome-moly on the steam header and super duplex at the seawater intake. Same size. Completely different pipe. The fluid, the temperature and the design life decide it. That is why the pipes and tubes here start with material rather than size, from API 5L line pipe for export pipelines to titanium for condenser bundles. GCC requisitions usually add an operator spec and corrosion allowance, so each grade page covers both, down to hardness and certification. Browse by family below or see the full product range.
Steel Pipe and Tube Families
Line Pipe and OCTG to API 5L and API 5CT
Oilfield pipe is bought to API, not ASTM, and the number after the X tells you the minimum yield in thousands of psi. Our API 5L line pipe pages run from Grade B up to X70 in PSL1 and PSL2, for transmission, gathering and water injection lines. Downhole, API 5CT casing and tubing covers J55 and K55 through L80 to P110. Both sit under the API line pipe and OCTG hub.
Carbon Steel Pipes and Mechanical Tubes
This is the family most piping specs start with, and for good reason. ASTM A106 and A53 carry the bulk of process and utility lines. A333 takes over when the design minimum drops below zero, and A179, A192 and A210 cover the tube side of boilers and exchangers. Cold drawn and hot finished mechanical tubing sits here too, all under carbon steel and mechanical pipes and tubes.
Chrome-Moly Alloy Steel Pipes for High Temperature
Add chromium and molybdenum to steel and you buy creep strength and oxidation resistance at high temperature. That is why ASTM A335 P11, P22 and P91 pipe, and A213 T-grade tubes, turn up on steam lines, headers and fired heaters in power stations and refineries. The full range is on the alloy and chrome-moly steel pipes and tubes hub.
Stainless Steel Pipes and Tubes
304L and 316L handle most general corrosion duty. For sustained high temperature, 321 and 347 are the stabilised options, while 904L and 254 SMO step in where chlorides or acids would pit a standard austenitic grade. Ferritic grades and instrumentation tubing complete the stainless steel pipes and tubes range.
Duplex and Super Duplex Pipes for Chloride Service
Duplex 2205 has roughly twice the yield strength of 316L, which often means a thinner wall, and it stands up to chloride stress corrosion cracking far better. When seawater or produced water is involved, super duplex grades such as UNS S32750 and S32760 push pitting resistance further again. Browse the duplex and super duplex pipes and tubes hub for individual grades.
Nickel Alloy Pipes for Severe Corrosion
When stainless runs out of road, nickel alloys take over: hot oxidising atmospheres, strong acids, and sour conditions that are simply too severe for anything else. Alloy 625, 825, 600, 800H, 400 and C276 are all covered. If only the wetted surface needs the alloy, CRA clad and lined pipe is often the cheaper route. Everything is grouped under nickel and exotic alloy pipes and tubes.
Copper Nickel and Titanium Tubes for Seawater
Copper nickel 90/10 and 70/30 resist seawater corrosion and marine fouling, which makes them a long-standing choice for cooling water and firewater mains. Titanium goes one step further and is specified for condensers and exchangers where chlorides would eventually beat almost any other metal. See copper nickel and titanium pipes and tubes.
Technical Data
How to Choose a Pipe Material: Selection Table
Material family |
Typical service |
Temperature |
Corrosion behaviour |
Sour service |
Main standards |
|---|---|---|---|---|---|
API line pipe and OCTG |
Pipelines, flowlines, well casing and tubing |
Ambient to moderate |
Relies on corrosion allowance, coating or inhibition |
PSL2 Annex H line pipe and L80 Type 1 OCTG are built for it |
API 5L, API 5CT |
Carbon steel |
Process, utility, boiler and exchanger lines |
Low temperature (A333) up to moderate high temperature (A106) |
Relies on corrosion allowance or coating |
Usable with hardness and HIC controls under ISO 15156-2 |
ASTM A106, A53, A333, A179, A192, A210 |
Chrome-moly alloy |
Steam, headers, fired heaters, hydroprocessing |
High temperature, into the creep range |
Better oxidation resistance than carbon steel |
Usable with hardness control and PWHT |
ASTM A335, A213, A691 |
Stainless steel |
Chemicals, utilities, instrumentation, potable water |
Cryogenic to high temperature |
Good general resistance; 304L and 316L can pit in warm chlorides |
Only inside the chloride, H2S and temperature limits of ISO 15156-3 |
ASTM A312, A213, A269, A358 |
Duplex and super duplex |
Seawater, produced water, offshore, desalination |
Generally kept below about 315 °C (600 °F) because of 475 °C embrittlement |
High pitting and chloride SCC resistance (PREN about 35 for 2205, 40 or more for super duplex) |
Permitted inside ISO 15156-3 limits with hardness control |
ASTM A790, A789, A928 |
Nickel alloys |
Severe sour service, acids, high-temperature oxidation |
Cryogenic to very high temperature |
Excellent in most media |
Widely used for the most severe sour conditions |
ASTM B444, B423, B622, B407; API 5LD for clad |
Copper nickel and titanium |
Seawater cooling, firewater, condensers |
Ambient to moderate |
Excellent in seawater |
Not a normal sour service choice |
ASTM B466, B111, B338, B861 |
Still weighing two options? The carbon vs stainless vs alloy steel selection guide and the duplex vs super duplex guide work through the trade-offs in more detail.
Sour Service Pipes: NACE MR0175 / ISO 15156 in Plain Terms
A line is in sour service when it carries hydrogen sulphide at a partial pressure high enough to crack susceptible steel. Across many fields in Oman and Saudi Arabia that is the normal condition rather than the exception, and it frequently decides which grades are even allowed onto the bid list.
NACE MR0175 / ISO 15156 is the rulebook. Part 2 deals with carbon and low-alloy steels, and the headline requirement is a hardness ceiling of 22 HRC (250 HV) in the pipe body, the weld and the heat-affected zone, backed by controls on chemistry and heat treatment. Part 3 deals with corrosion-resistant alloys. Each alloy group there has its own limits on H2S partial pressure, chlorides, temperature and pH, and its own hardness cap.
Two tests come up again and again. Hydrogen-induced cracking (HIC) is tested to NACE TM0284 and is normally required for carbon steel line pipe and plate. Sulphide stress cracking (SSC) is tested to NACE TM0177.
How the families line up:
- Line pipe: API 5L PSL2 ordered to Annex H is the sour service route.
- OCTG: L80 Type 1, C90 Type 1 and T95 Type 1 are acceptable at all temperatures under ISO 15156-2, and so are the lower-strength J55 and K55. N80 and P110 are acceptable only above minimum temperatures set in the standard, which usually keeps them out of cooler sections of a sour well.
- Process pipe: carbon steel and chrome-moly work when hardness, chemistry and PWHT meet ISO 15156-2.
- Corrosion-resistant alloys: 316L is allowed only within tight limits. Duplex and super duplex go further, and nickel alloys such as 625 and 825 cover the most severe conditions.
- Copper nickel and titanium are not usual sour service choices.
Put your sour service and testing requirements (HIC, SSC, hardness survey) in the RFQ and they will be confirmed at quotation. For a deeper look, read the NACE MR0175 sour service guide or the upstream oil and gas and sour service page.
Pipe Price: What Drives the Quotation
Pipe prices track nickel, molybdenum, chromium and steel markets week to week, so they are quoted per enquiry rather than published. The factors that move the number most:
- Grade and heat. Nickel and molybdenum content drive alloy cost more than anything else.
- Size and wall. Very heavy walls, or very small or very large diameters, can change the production route.
- Quantity. Many alloy and API items carry mill minimums.
- Stock or mill order. Whether the exact size and grade is available now or has to be rolled.
- Certification. EN 10204 3.1 or 3.2.
- Third-party inspection. The agency, scope and witness points all add time.
- Sour service testing. HIC, SSC and hardness surveys add both time and cost.
- Incoterm and destination port.
Quotations are available in USD, OMR, AED, SAR, QAR, KWD and BHD, on EXW, FOB, CFR or CIF terms.
What to send for a fast quote
Grade, standard, OD, wall thickness or schedule, length, quantity, end finish (plain, bevelled or threaded), certification level, inspection requirement, destination port and required date.
Mill Test Certificates, Inspection and PMI
Material is supplied with EN 10204 3.1 mill test certificates as standard, and EN 10204 3.2 certificates on request. Inspection by the buyer's nominated third-party agency can be arranged; state your requirement in the RFQ. On alloy, stainless, duplex and nickel grades, positive material identification (PMI) confirms the grade length by length, which is the simplest protection against a mixed-up bar of 304 turning up where 316L was specified. The MTC and EN 10204 certification guide explains exactly what separates a 3.1 from a 3.2.
Pipe Packing, Delivery and Gulf Site Conditions
Lead time is confirmed at quotation.
Packing is prepared for sea freight and for weeks of outdoor laydown in Gulf heat:
- End caps on plain ends and bevel protectors on bevelled ends
- Small bores bundled and strapped to suit site handling
- Varnish or temporary coating on carbon and alloy steel where specified
- Stainless, duplex and nickel alloys kept apart from carbon steel so they do not pick up iron contamination
- UV-stable caps and covers for anything stored outside, because ordinary plastic caps go brittle quickly under Gulf sun
The climate matters for selection, not just packing. Coastal sites carry airborne chlorides that can pit 304L, and at high ambient temperatures austenitic stainless becomes vulnerable to chloride stress corrosion cracking. It is one reason duplex, super duplex and copper nickel appear so often in desalination and seawater systems. Exposed lines also run hotter than the process alone would suggest when they sit in direct summer sun, which is worth allowing for at design stage. And sand gets everywhere, so end protection has to stay on until the pipe is ready to weld.
Matching Pipe Fittings and Flanges
A line is only as reliable as its weakest component, so match the fittings and flanges to the pipe:
- Pipe fittings and flanges, all materials
- Carbon steel fittings and flanges
- Low temperature fittings and flanges to go with A333 pipe
- High yield pipeline fittings and flanges to go with API 5L X-grade line pipe
- Alloy steel fittings and flanges to go with A335 chrome-moly pipe
- Stainless steel fittings and flanges
- Duplex fittings and flanges
- Nickel alloy fittings and flanges
Pipes and Tubes by Industry
- Oil and gas: line pipe, OCTG, carbon steel and duplex process pipe
- Upstream oil and gas and sour service: PSL2 sour line pipe, L80 tubing, CRA pipe
- LNG and gas processing: low-temperature carbon steel and austenitic stainless
- Refinery and petrochemical: chrome-moly, stainless and nickel alloys
- Power generation: A335 and A213 material for boilers, superheaters and headers
- Desalination and water treatment: super duplex, copper nickel and titanium
- Fertilizer: stainless and special grades for urea and ammonia service
- Marine and offshore: duplex, super duplex and copper nickel seawater systems
Pipes and Tubes FAQ
Which pipe material should I specify for sour gas service?
It depends on H2S partial pressure, chlorides, temperature and pH. Carbon steel and API 5L PSL2 line pipe can be used when hardness is held to 22 HRC (250 HV) and HIC resistance is proven under NACE MR0175 / ISO 15156-2. Where conditions go beyond those limits, duplex, super duplex or nickel alloys are selected within the limits of ISO 15156-3. State your sour service and testing requirements in the RFQ.
Can I get the same grade in both seamless and welded pipe?
Most grades are produced in both forms. Seamless pipe is usually specified for high pressure, high temperature and sour service, while welded pipe (ERW, SAW or EFW) is more economical in large diameters and thin walls. Tell us which form your specification calls for.
What lengths do you supply for container shipment?
Pipe is supplied in random lengths as defined by the product standard, or cut to fixed lengths on request. Lengths of 5.8 m fit a 20 ft container and 11.8 m fit a 40 ft container, which suits sea freight into GCC ports.
Do you supply EN 10204 3.2 certificates with third-party inspection?
EN 10204 3.1 certificates are supplied as standard and EN 10204 3.2 certificates are available on request. Inspection by the buyer's nominated third-party agency can be arranged; state your requirement in the RFQ.
Which currencies and Incoterms do you quote in?
Quotations are available in USD, OMR, AED, SAR, QAR, KWD and BHD, on EXW, FOB, CFR or CIF terms.
What do I need to send for a quotation?
Send the grade, standard, OD, wall thickness or schedule, length, quantity, end finish, certification level, inspection requirement, destination port and required date. Attach your project or operator material specification if one applies.
Request a Quote for Pipes and Tubes
Send over the grade, size, quantity and destination port, and attach the operator specification or datasheet if you have one. Every enquiry is checked against the governing standard before the offer goes out, so anything missing or contradictory gets flagged early rather than at the inspection stage.