Steel Pipes and Tubes 

Steel Pipes and Tubes Manufacturer, Supplier and Exporter 

Solitaire Overseas is a manufacturer, supplier and exporter of pipes and tubes based in Mumbai, India. We supply seamless and welded pipes and tubes across stainless steel, carbon steel, alloy steel, duplex and super duplex, corten steel, nickel alloy, cupro-nickel and titanium, in the sizes, schedules and wall thicknesses used by process plants, refineries, boiler makers and heat exchanger fabricators.

Whether you need a single trial length or a project quantity against a bill of materials, our team can quote against your specification, grade and end preparation. Send your requirement and we will respond with availability and pricing.

Pipe vs Tube: What Actually Changes

The terms are used interchangeably in the market, but in engineering procurement they are specified differently. A pipe is designated by Nominal Pipe Size (NPS) or Nominal Bore (DN) together with a schedule that fixes the wall thickness; the outside diameter stays constant for a given NPS while the bore changes with schedule. A tube is designated by its measured outside diameter and wall thickness, and is generally held to tighter dimensional tolerances.

In practice: if the drawing calls out a schedule, you are buying pipe. If it calls out an OD and a wall in millimetres or gauge, you are buying tube. Both are rigid, permanent products, unlike hose, which is flexible and portable.

How Pipes and Tubes Are Classified

Beyond the pipe/tube split, tubular products are grouped by their end use, and knowing which group your requirement falls into makes specifying far easier.

Tube use groups:

• Pressure tube: conveys pressurised fluid while heat is applied externally, which is why boiler and superheater tubes sit here. Ordered to actual OD and minimum or average wall.
• Structural tube: round, square, rectangular and special sections for welded, riveted or bolted construction.
• Mechanical tube: made to the customer's dimensions rather than a standard size table, for machined and fabricated components.

Pipe use groups:

• Standard pipe: standard weight, extra strong and double extra strong, for general fluid conveyance and light structural work.
• Line pipe: for transmitting oil and gas, supplied plain, bevelled, threaded, grooved or flanged to suit the joint.
• Oil country tubular goods (OCTG): drill pipe, casing and tubing for well service.
• Water well pipe: drive pipe, reamed and drifted pipe, driven well pipe and casing.
• Pressure pipe: carries fluid at high pressure or temperature but without external heat applied.

Special applications such as conduit pipe and tubular piling sit outside these groups. Pipes are further described by the medium they carry (water, steam, gas, oil, slurry), by finish (plain or corrugated), by joining method (welded, threaded, flanged, coupled) and by lining or coating (epoxy, cement mortar, rubber, galvanised, PE).

Markings on Pipes and Tubes: What to Check on Receipt

Requirements vary by standard, but material is normally marked continuously along its length with the information below. Checking it at goods-in is the quickest way to confirm you received what you ordered:

• Nominal pipe size / nominal bore
• Schedule or wall thickness
• Specification and grade
• Method of production, seamless or welded
• Heat number, for traceability back to the melt
• Manufacturer name or logo 

Sizes, Schedules and End Finishes

Pipes and Tubes Dimensions Chart

Common schedules requested: Sch 5, Sch 10, Sch 20, Sch 40 / STD, Sch 80 / XS, Sch 120, Sch 160 and XXS. Tubes, by contrast, are ordered by actual OD and wall thickness (or gauge), which is why heat exchanger and instrumentation drawings never mention a schedule. If you need to estimate mass for a shipment, use our weight calculators or the steel weight formula.

End preparations: plain end, bevelled for butt welding, threaded, grooved or flanged. Because ranges vary by grade and by mill, send the exact size, wall, quantity and end preparation with your enquiry and we will confirm what can be supplied against it.

Testing and Inspection

Non-destructive testing is normally built into the end of the production line, because it verifies the product without damaging it. The methods you are most likely to see referenced on a specification are:

• Ultrasonic testing: sound waves are reflected from internal and external surfaces and compared against a calibration standard to reveal cracks and internal defects.
• Eddy current testing: discontinuities are detected by comparing the electrical conditions in two search coils, widely used on heat exchanger tubing.
• Hydrostatic testing: the item is filled with water and pressurised at or above its service pressure.
• Magnetic particle testing: for ferromagnetic material; magnetic particles reveal the field distortion caused by a flaw.
• Radiographic (X-ray) testing: used mainly to confirm weld soundness.
• Dye penetrant testing: surface-breaking cracks are revealed by penetrant drawn out into a developer, with fluorescent dye used where higher sensitivity is required.

Specify the tests your project requires at enquiry stage, along with the inspection and documentation you need, so it can be confirmed before order.

How to Choose the Right Material

Material selection is driven by the properties the service demands, and corrosion resistance is usually the biggest single factor in the price you pay:

• Corrosion and chemical resistance: the decisive property in most process applications. Specialist alloys can cost many times more than standard stainless and take longer to fit and weld, so over-specifying is expensive.
• Ductility and malleability: these govern how easily material can be formed or bent to route, which matters for tubing runs where fittings would otherwise be needed.
• Hardness: an advantage in high-pressure systems, a disadvantage in machining and fabrication time.
• Elasticity: allows piping to absorb thermal expansion and contraction in service.
• Thermal conductivity: maximised in heat exchanger tubing, minimised where heat transfer must be prevented.

Share the medium, operating temperature, design pressure and any chloride or acid exposure with your enquiry, and we can help match the grade to the duty.

Why Buy Your Steel Pipes and Tubes from Solitaire Overseas

• A single source across stainless, carbon, alloy, duplex, corten, nickel, copper-nickel and titanium, meaning one enquiry instead of six vendors.
• Both pipe and tube designations are supplied, in seamless and welded form.
• Export experience across the Middle East, Africa, Europe, South America and Asia, with sales representatives in Saudi Arabia, Kuwait, Qatar, Turkey, Kazakhstan, Greece, Oman, Yemen, UAE, Singapore, Thailand, Indonesia, Iran, South Africa, South America, Vietnam, Taiwan, Romania, Brazil, Egypt, Philippines, Malaysia, Australia and Germany.
• Documentation and approvals are listed on our Certificates page.
• Enquiries answered within 24 hours; our team is available 9:00 AM – 7:00 PM, all days.

Industries We Supply 

Oil and gas · petrochemical and refining · power generation · chemical and fertiliser · pharmaceutical · desalination and water treatment · pulp and paper · sugar and distillery · shipbuilding and marine · food processing and dairy · general engineering and construction.