BS 3059

BS 3059 Steel Pipe
BS 3059 is the renowned standard for Steel boiler and superheater tubes, setting the benchmark for tubes not exceeding 127 mm in outside diameter and 12.5 mm in thickness. This standard, published by The British Standards Institution (BSI), the esteemed national standards body of the United Kingdom, ensures that you receive tubes of the highest quality. With UNIACERO, you can be assured of steel pipes that meet the stringent requirements of BS 3059, including specified room temperature properties. Our commitment to excellence ensures that our products are not only robust and durable but also adhere to the highest standards of production and quality control.
BS 3059 Specification
Our BS 3059 steel pipes come in various specifications, ensuring a wide range of options for our clients. These include Carbon/Alloy Seamless Steel Pipe, ERW/LSAW/DSAW Steel Pipe, and Spirally Welded Steel Pipe. Each pipe is meticulously crafted, ensuring precision in dimensions, production procedures, steel grades, surface coatings, end types, joint methods, and machining services. With UNIACERO, you get a product that is not just compliant with international standards but also tailored to your specific needs.
| Production Standard | BS3059 |
| Manufacturing Processes | HFS (Hot finished seamless) |
| CFS(Cold finished seamless) | |
| ERW(Electric resistance welded including induction welded) | |
| CEW(Cold finished electric resistance welded including induction welded) | |
| Outside Diameter | OD ≤127mm |
| Wall Thickness | W.T.≤12.5mm |
| Pipe Length | 3 – 12 mtrs meters |
| Steel Grade | 320 Seamless |
| 320 Welded | |
| Corrosion Prevention | Lacquer, Varnish, Oiling, Galvanizing |
| FBE, 2LPP, 3LPP, 2LPE, 3LPE | |
| End Processes | Square Cut, Bevelling, Threading, Grooving , Shouldering |
| Further Processing | Welding, Bending, Hole Drilling, Punching, Swaging, Tapering, Flaring, Expanding |
BS 3059 Dimension Table

The dimensions of our BS 3059 steel pipes are meticulously crafted to precision. With an outer diameter ranging from 19.05-114.3mm and a wall thickness between 2-14mm, our pipes are designed to fit a variety of applications. The maximum length we offer is 16m, ensuring that you have ample length for any project. Every dimension is carefully calibrated to ensure optimal performance and durability.
| Outside Diameter | Tube Thickness (mm) | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| mm | 2.0 | 2.3 | 2.6 | 2.9 | 3.2 | 3.6 | 4.0 | 4.5 | 5.0 | 5.6 | 6.3 | 7.1 | 8.0 | 8.8 | 10.0 | 11.0 | 12.5 |
| 25.4 | ● | ● | ● | ● | ● | ● | ● | ● | ● | ||||||||
| 26.9 | ● | ● | ● | ● | ● | ● | ● | ● | ● | ||||||||
| 31.8 | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ||||||
| 33.7 | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ||||||
| 38 | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ||||
| 42.4 | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | |||||
| 44.5 | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ||||
| 48.3 | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ||||
| 51 | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | |||
| 57 | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ||||
| 60.3 | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | |||
| 63.5 | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | |||
| 70 | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | |||
| 76.1 | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | |||
| 82.5 | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ||||
| 88.9 | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ||||
| 101.6 | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | |||||
| 114.3 | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | ||||||
| 127 | ● | ● | ● | ● | ● | ● | ● | ● | ● | ● | |||||||
Chemical Requirements of BS 3059
At UNIACERO, we understand the importance of the chemical composition in steel pipes. Our BS 3059 steel pipes are manufactured with a precise chemical composition, ensuring high resistance to corrosion, enhanced durability, and optimal performance. Each pipe undergoes rigorous testing to ensure that it meets the stringent chemical requirements set by the BS 3059 standard.
| Steel grade | Method of manufacture | Chemical composition (ladle analysis) (see notes 1 and 2) | Mechanical properties at room temperature (see note 3) | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| C | Mn | Si | P | S | Re | Rm | A | Flattening test constant C | Drift expanding test: increase in D | |||||||
| max. | min. | max. | min. | max. | max. | max. | min. | min. | max. | min. | d/D ratio | |||||
| ≤ 0.6 | >0.6 ≤ 0.8 | >0.8 | ||||||||||||||
| – | – | % | % | % | % | % | % | % | N/mm2a | N/mm2 | N/mm2 | % | – | % | % | % |
| 320 | Seamless Welded | 0.16 | 0.30 | 0.70 | 0.10 | 0.35 | 0.04 | 0.04 | 195 | 320 | 480 | 25 | 0.10 | 12 | 15 | 19 |
| 320 | Seamless Welded | 0.16b | 0.30 | 0.70 | – | 0.35 | 0.04 | 0.04 | 195 | 320 | 480 | 25 | 0.10 | 12 | 15 | 19 |
| ||||||||||||||||
Mechanical Requirements of BS 3059
Mechanical properties are crucial for the performance of steel pipes. Our BS 3059 pipes boast a Tensile Strength of 360-500 Mpa and a Yield Strength of 235 Mpa. With an elongation of 24 and a flatten coefficient of 0.1, our pipes are designed to withstand high pressures and temperatures, ensuring longevity and reliability in any application.
| Steel grade | Method of manufacture | Chemical composition (ladle analysis) (see notes 1 and 2) | Mechanical properties at room temperature (see note 3) | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| C | Mn | Si | P | S | Re | Rm | A | Flattening test constant C | Drift expanding test: increase in D | |||||||
| max. | min. | max. | min. | max. | max. | max. | min. | min. | max. | min. | d/D ratio | |||||
| ≤ 0.6 | >0.6 ≤ 0.8 | >0.8 | ||||||||||||||
| – | – | % | % | % | % | % | % | % | N/mm2a | N/mm2 | N/mm2 | % | – | % | % | % |
| 320 | Seamless Welded | 0.16 | 0.30 | 0.70 | 0.10 | 0.35 | 0.04 | 0.04 | 195 | 320 | 480 | 25 | 0.10 | 12 | 15 | 19 |
| 320 | Seamless Welded | 0.16b | 0.30 | 0.70 | – | 0.35 | 0.04 | 0.04 | 195 | 320 | 480 | 25 | 0.10 | 12 | 15 | 19 |
| ||||||||||||||||
Steel Grades in BS 3059
We offer a diverse range of steel grades to cater to the varied needs of our clients. Whether you require low tensile carbon steel tubes or carbon, alloy, and austenitic stainless steel tubes with specified elevated temperature properties, UNIACERO has got you covered. Each grade is carefully selected to ensure optimal performance and longevity.
- Grade 320
- Grade 360
- Grade 460
Production Tolerance of BS 3059
Precision is key in the production of steel pipes. At UNIACERO, we adhere to strict production tolerances to ensure that each pipe meets the exact specifications of our clients. Our cold-drawn pipes have a tolerance of +/-0.1mm, while our cold-rolled pipes have a tolerance of +/-0.05mm. With us, you can be assured of products that are not only of the highest quality but also precisely tailored to your needs.
Cold finished electric resistance welded including induction welded (CEW)
Outside diameter: + 0.5 % with a minimum tolerance of + 0.10 mm
Thickness:+ 7.5 %
Outside diameter, thickness and size of weld upset
The toleranceg on outside diameter shall include ovality and those on thickness shall include eccentricity.
a) Hot finished seamless (HFS)
Outside diameter: ± 1 % with a minimum tolerance of : ±0.50 mm
Thickness: ± 12.5 %
b) Cold finished seamless (CFS)
Outside diameter: ±0.5 % with a minimum tolerance of ± 0.10 mm
Thickness: ± 7.5 %
c) Electric resistance welded including induction welded (ERW)
Outside diameter: ±0.75 % with a minimum tolerance of : ±0.30 mm
Thickness: up to and including 3.2 mm ± 10 %
over 3.2 mm ± 7.5 %
10.3 Length
Unless otherwise specified by the purchaser [see 2.2 e)] tubes shall be supplied as random lengths.
NOTE The actual range of the random lengths may be the subjcet of agreement between the mnnufneturer and the purchnser.
Where the length is specified as “exact length” or “cut length” the permissible deviation shall be + 6,- 0 mm for lengths up to and including 6 m.
For every 3 m increase in length above 6 m, the plus tolerance shall be increased by 1.5 mm with a maximum of 12.0 mm.



