SA334 Grade 1 Low-Temperature Carbon Steel Tubes
Dinesh Tube India supplies ASTM A334 / ASME SA334 Grade 1 carbon steel tubes from Mumbai to heat exchanger fabricators, EPC contractors and plant maintenance teams in India and abroad. A334 Grade 1 is a low-temperature carbon steel (LTCS) tube, impact tested at −45 °C (−50 °F), for heat exchangers, condensers and coolers in cold service.
We supply A334 Gr 1 tubes in seamless and welded form, in minimum wall thickness, cut to length, with an EN 10204 3.1 mill test certificate showing impact test results. Send us your OD, minimum wall, length and quantity for a quote.
What Is ASTM A334 Grade 1?
ASTM A334/A334M is the standard specification for seamless and welded carbon and alloy steel tubes for low-temperature service. ASME adopts it as SA334 in Boiler and Pressure Vessel Code Section II. The specification covers several grades in minimum wall thickness; Grade 1 is the plain carbon-manganese grade, with 0.30% carbon maximum and 0.40–1.06% manganese.
What makes A334 different from ordinary carbon steel tubes such as SA179 is the Charpy impact test at −45 °C. Plain carbon steel can become brittle in cold service; A334 Grade 1 is heat treated and tested to show it stays tough at low temperature. That makes it the standard tube for heat exchangers handling refrigerants, LPG, ammonia and chilled process streams. General requirements for tolerances and testing come from ASTM A1016/A1016M.
ASTM A334 Grade 1 Chemical Composition
Values in weight %. For each 0.01% reduction below 0.30% carbon, a 0.05% increase in manganese above 1.06% is permitted, up to 1.35% Mn.
A334 Grade 1 Mechanical Properties & Impact Test
Sub-size specimens are used for thinner walls, with reduced energy values per the specification.
Heat Treatment & Testing
A334 Grade 1 tubes are normalised (or normalised and tempered), or for seamless tubes made with controlled hot-working and finishing temperatures, so the grain structure gives good toughness at low temperature. Each lot is tested as required by A334 and A1016:
Need A334 Gr 1 tubes for a low-temperature exchanger? Send your OD, minimum wall, length, quantity and seamless or welded requirement to kamlesh@dineshtube-india.com or call +91 83559 10913. You can also send an enquiry.
Common A334 Grade 1 Tube Sizes
Other sizes on request. Some heavy-wall sizes may not meet the impact requirement and are not available under A334.
ASTM A334 Grade 1 Equivalent Material
Nearest equivalents only. Chemistry, strength and impact test temperature differ slightly; check against your design code before substituting.
Types of A334 Gr 1 Tubes
A334 Gr 1 Seamless Tubes
A334 Gr 1 Welded Tubes
A334 Gr 1 vs A334 Gr 6 & A333 Gr 6
For low-temperature piping, see our LTCS pipes page. Matching A420 WPL6 fittings and A350 LF2 flanges are also available. To compare all grades, see carbon steel tubes.
A334 Grade 1 Tube Applications
For a full range of exchanger tube materials, see our heat exchanger tubes page.
ASTM A334 Grade 1 Tubes: FAQs
What is ASTM A334 Grade 1?
ASTM A334 Grade 1 is a carbon steel tube for low-temperature service. A334 covers seamless and welded carbon and alloy steel tubes in minimum wall thickness; Grade 1 is the plain carbon-manganese grade, impact tested at −45 °C (−50 °F) so the tube stays tough in cold service. ASME adopts it as SA334 Grade 1.
What is the difference between A334 Gr 1 and A334 Gr 6?
Both are carbon steel grades impact tested at −45 °C. Grade 6 is stronger, with a minimum tensile strength of 415 MPa and yield of 240 MPa, against 380 MPa and 205 MPa for Grade 1. Grade 1 is softer and easier to expand into tube sheets; Grade 6 is chosen when the design needs higher allowable stress.
What is the difference between A334 and A333?
ASTM A334 covers tubes, ordered by outside diameter and minimum wall, mainly for heat exchangers. ASTM A333 covers pipes, ordered by nominal pipe size and schedule, for low-temperature piping. A333 Grade 6 pipe is the piping counterpart of A334 Grade 6 tube.
What is the minimum design temperature for A334 Grade 1 tubes?
A334 Grade 1 is impact tested at −45 °C (−50 °F), so it is normally used for design temperatures down to about −45 °C. For colder service, such as LNG or liquid nitrogen, nickel steels (A334 Grade 3 or 8) or austenitic stainless steel tubes are used instead.
Is A334 Grade 1 seamless or welded?
It can be either. A334 allows both seamless and welded tubes, and the purchaser specifies which. Welded tubes get a flange test and a reverse flattening test in place of the flare test. Many low-temperature heat exchanger specifications call for seamless tubes.
What is the equivalent of ASTM A334 Grade 1?
The nearest equivalents are EN 10216-4 P215NL (seamless) or EN 10217-4 P215NL (welded), and JIS G3464 STBL380. These are close but not identical in chemistry, strength and impact test temperature, so check them against your design code before substituting.
Export Destinations for A334 Gr 1 Tubes
We export ASTM A334 Grade 1 tubes to the Middle East (UAE, Saudi Arabia, Qatar, Kuwait, Oman, Bahrain, Iraq, Jordan), Africa (Nigeria, Egypt, South Africa, Kenya, Ghana, Algeria, Morocco, Tunisia), Asia (Japan, South Korea, Singapore, Malaysia, Indonesia, Thailand, Vietnam, Philippines, Bangladesh, Sri Lanka), Europe (Italy, Spain, Portugal, France, Netherlands, Belgium, Poland, Romania, Turkey, United Kingdom), and the Americas (United States, Canada, Mexico, Brazil, Chile, Peru, Colombia, Argentina).