Pipes and tubes are hollow sections used to convey fluids and gases under pressure, to transfer heat, and as structural members. We supply them as a dealer, supplier and exporter in a full range of materials – from everyday carbon steel and SS 304 to duplex, nickel alloys and titanium for severe service.
The right choice depends on three things: the material (corrosion and temperature resistance), the manufacturing route (seamless or welded), and the dimensions (diameter, wall thickness and tolerance class). The sections below cover each in detail.
Both are hollow sections, but they are ordered and toleranced differently. Getting this right avoids costly mistakes at the enquiry stage.
| Pipe | Tube | |
|---|---|---|
| Ordered by | Nominal size (NPS / DN) + schedule | Actual outside diameter + wall thickness |
| Size meaning | NPS is a nominal designation; OD is fixed per NPS | OD is the true measured dimension |
| Wall | Schedule number (5S, 10S, 40, 80, 160, XXS…) | Stated in mm, inch or gauge (SWG / BWG) |
| Tolerances | Wider – e.g. wall −12.5% (ASTM A312) | Tighter, for close-fit and heat-transfer duty |
| Typical use | Conveying fluids & gases; pressure piping | Heat exchangers, instrumentation, structures, machining |
| Typical standards | ASTM A312, A106, A53, A790; ASME B36.10M / B36.19M | ASTM A213, A269, A249, A789 |
The manufacturing route affects price, available sizes, tolerances and how the material behaves in service.
Produced by piercing a solid round billet and elongating it over a mandrel, then sizing – and cold drawing for smaller sizes and tighter tolerances. No weld seam anywhere in the pipe.
Strip or coil is formed into a cylinder and the edges are fused by resistance heating and pressure, without filler metal. The weld bead is trimmed and the pipe is sized and heat treated as required.
Plate or sheet is rolled and welded with filler metal – usually submerged arc – in a straight (longitudinal) or spiral seam. The route used for large-diameter and heavy-wall pipe.
Welded tube that is cold drawn and bright annealed to refine the weld, improve surface finish and hold close dimensional tolerances – an economical alternative to seamless tube.
Any grade & size on request. Material is supplied with mill test certificates traceable to the heat number.
| Material Family | Grades | Standards | Typical Service |
|---|---|---|---|
| Austenitic Stainless Steel | TP304, TP304L, TP316, TP316L, TP321, TP347, TP310S, TP317L | ASTM A312, A213, A269, A249 | Chemical, food & dairy, pharma, general process |
| Ferritic & Martensitic Stainless | 409, 410, 430, 439 | ASTM A268 | Exhausts, heat exchangers, mild corrosion service |
| Duplex & Super Duplex | 2205 (S31803 / S32205), 2507 (S32750), S32760 | ASTM A790, A789 | Seawater, desalination, oil & gas, chemical tankers |
| Nickel Alloys | Inconel 600, Inconel 625, Monel 400, Hastelloy C-276, C-22 | ASTM B167, B444, B165, B622 | Severe corrosion, high temperature, FGD, sour service |
| Titanium | Grade 2, Grade 5 (Ti-6Al-4V) | ASTM B861, B338 | Seawater condensers, chemical plant, desalination |
| Carbon Steel | A106 Gr. B / Gr. C, A53 Gr. A / B, IS 1239 | ASTM A106, A53, IS 1239 | Steam, water, oil lines, structural, general piping |
| Alloy Steel | P5, P9, P11, P22, P91 (T-grades in tube), 4130 | ASTM A335, A213, A519 | Boilers, superheaters, refinery high-temperature lines, oil-tool tubing |
| Boiler & Heat-Exchanger Tubes | SA 210 Gr. A1 / C, T11, T22, T91, SA 192 | ASTM A210, A213, A192 | Water-wall, economiser, superheater and reheater tubes |
| Cupro-Nickel | 90/10 (C70600), 70/30 (C71500) | ASTM B111, B466, B467 | Seawater piping, condenser and heat-exchanger tubes, desalination |
| Low-Temperature Steel | A333 Gr. 6, Gr. 3 | ASTM A333 | LPG, cryogenic and cold-climate piping |
| Copper, Brass & Aluminium | C11000, C26000, 6061, 6063 | ASTM B88, B135, B210 / B221 | Plumbing, heat transfer, light structures |
Standard stock sizes plus cut-to-length and custom dimensions to your drawing.
Wall thickness tolerance is typically −12.5% of nominal (ASTM A312 / A106). See the Pipe Schedule Chart.
Pipe ends are protected with caps; bevelled ends are protected against impact in transit.
*On request. Sanitary tubing (ASTM A270) can be supplied with specified internal Ra values.
Material is supplied to the specification, grade and edition stated on your purchase order.
Understanding the route helps you specify the right product – and read a mill certificate with confidence.
Steel is melted (EAF / AOD or VOD refining for stainless) and cast into billets, blooms or slabs. Each melt receives a heat number that follows the material to delivery.
Seamless: the billet is heated and rotary-pierced, then elongated over a mandrel and sized. Welded: strip or plate is formed into a cylinder and welded (ERW without filler, EFW with filler).
Austenitic stainless is solution annealed (typically 1040–1120 °C) and rapidly quenched to dissolve carbides; duplex grades are annealed and quenched to balance ferrite and austenite. Carbon and alloy pipe is normalised or tempered as the standard requires.
Scale is removed by pickling and the passive layer restored; tubes may be cold drawn and bright annealed for closer tolerances and a better surface.
Pipes are straightened and sized to meet diameter, ovality and straightness tolerances, then cut to length and end-finished.
Hydrostatic or non-destructive testing, final inspection, stencil marking with specification, grade, size and heat number – then packing for dispatch.
Tests reported on the mill certificate, plus additional testing arranged on request.
Full composition of the heat by optical emission spectrometry, reported on the mill certificate.
Tensile strength, yield strength and elongation; hardness where required by the specification.
Each length pressure tested to the test pressure required by the product specification.
Eddy current or ultrasonic examination – permitted in place of the hydrostatic test by several standards.
Flattening, flaring and reverse-bend tests confirm ductility and weld soundness in pipe and tube.
Intergranular corrosion for stainless; pitting and intermetallic phase checks for duplex grades.
Positive material identification by XRF/OES, plus OD, wall, length, ovality and straightness checks.
Mill test certificates as per EN 10204 3.1 (3.2 with third-party inspection), with heat-number traceability.
Material reaches site in the condition it left the warehouse – free from damage and contamination.
Plastic caps keep the bore clean; bevelled ends are protected against impact damage.
Hexagonal bundles with steel strapping for pipe; wooden crates or pallets for tube and export shipments.
Stainless and nickel alloys are handled separately from carbon steel, with non-metallic slings where required.
Each length is stencilled with specification, grade, size and heat number; bundles carry matching tags.
From refinery process lines to dairy plants and structural fabrication.
Process lines, flowlines, heat exchangers, sour service piping
Corrosive media, acid handling, reactor and scrubber piping
Boiler and superheater tubes, condensers, feedwater lines
Sanitary tubing, CIP lines, hygienic process systems
Seawater intake, RO systems, firewater and cooling lines
Columns, handrails, scaffolding, architectural work
Cut-to-size pipe for fabricators, skids and equipment builders
Ballast, bilge and seawater systems in duplex and Cu-Ni
Send these details and we can quote accurately – usually the same working day.
Seamless is preferred for high pressure, high temperature and critical or sour service because there is no weld seam. Modern welded pipe is fully tested and is economical for general service, larger diameters and thin walls. Many specifications (for example ASTM A312) cover both.
SS 316 contains molybdenum (around 2–3%), which greatly improves resistance to pitting in chlorides – seawater, coastal air, brines and many chemicals. SS 304 is suitable for general and food-grade service at lower cost. The "L" versions have low carbon for better resistance to corrosion after welding.
For a given NPS the outside diameter is fixed, so a higher schedule means a thicker wall and a smaller bore. A thicker wall carries more pressure. The actual allowable pressure depends on material, temperature, joint efficiency and corrosion allowance, and is calculated to the applicable design code.
Yes. Material can be cut to the exact lengths you need, and we supply both project quantities and smaller requirements for fabrication and maintenance work.
Yes – material is supplied with mill test certificates as per EN 10204 3.1, with the heat number on the certificate matching the marking on the pipe. Type 3.2 certificates and third-party inspection can be arranged on request.
Most pipe specifications permit the wall to be up to 12.5% under the nominal thickness (for example ASTM A312 and A106). Tubes are made to tighter tolerances. Always design to the minimum wall, not the nominal.
Specification, grade, size, schedule or wall, length, quantity and certification – we'll confirm availability, price and delivery.
