Stainless Steel Seamless Tubes Manufacturer in India

Stainless Steel Seamless Tubes are hollow, jointless tubes manufactured from solid stainless steel billets through piercing or extrusion, followed by hot finishing or cold drawing and heat treatment. They are specified by their actual outside diameter (OD), wall thickness and length, with dimensional tolerances and delivery conditions governed by the applicable product standard. Common specifications include ASTM A213 for boiler, superheater and heat-exchanger tubes, ASTM A269 for general-service tubing and ASTM A789 for duplex stainless steel tubing.

Kamal Steels is a Mumbai-based manufacturer and stockist of stainless steel seamless tubes, established in 1984. We cater to requirements in austenitic and duplex stainless steel grades for heat exchangers, boilers, condensers, instrumentation and industrial applications, subject to grade, size and availability.

Buyers can enquire about tube grades, actual outside diameters, wall thicknesses, length requirements, manufacturing specifications, surface finish, testing and material test certificates (MTC).

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Share your required grade, outside diameter, wall thickness, applicable standard and quantity with Kamal Steels to check availability and request a quotation.

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Stainless Steel Seamless Tube Specifications

The table describes the general industry framework. Kamal Steels' actual ranges.

Common Grades of Stainless Steel Seamless Tubes

Grade choice depends on the fluid, temperature, chloride level and welding route. A grade name alone does not establish suitability for a given pressure, temperature or corrosive environment; that is decided by the design code, the product specification and the service conditions. The tables describe how each family is generally used. Chemical composition and mechanical values are not listed because they differ by grade and by specification; they appear in the specification tables and on the mill certificate. Not every grade is covered by every standard or available in every size. grades and sizes supplied.

Austenitic Grades

Duplex and Super Duplex Grades

Stainless Steel Tube Sizes and Dimensions

Outside Diameter and Wall Thickness

A tube is sized by its actual outside diameter (OD) and a wall thickness, in mm or inches, with wall sometimes given as a gauge. Unlike pipe, there is no nominal size that differs from the real diameter: a 25 mm OD tube measures 25 mm across. State OD and wall thickness together in every enquiry. Kamal Steels' OD, wall and length ranges before adding any range or size chart to this page.

Minimum Wall and Average Wall

Some tube specifications allow the buyer to order on a minimum-wall or an average-wall basis, and the two are not the same. State which basis the order uses so the delivered wall matches the design calculation.

Dimensional Tolerances

Tolerances on outside diameter, wall thickness and length come from the product specification and the general-requirements standard it cites, and they vary with size and product. Do not apply pipe tolerances to tube. State the specification on the order and ask for the applicable tolerance table where tolerance is critical.

Heavy Wall and Large Diameter Tubes

Heavy-wall and large-diameter tubes are common requirements in pressure service and heat exchangers. They are generally hot finished, while smaller sizes and thinner walls are more often cold finished. Availability depends on grade, size and specification. what Kamal Steels supplies in heavy wall and large diameter.

Types of Seamless Stainless Steel Tubes

This page covers round seamless tube. Oval and special-shape tubes, and ferritic and martensitic tube grades, are outside its scope.

How to Write a Tube Order Description

Use the following details when preparing a tube enquiry. The example is an ordering checklist, not an indication of stock.

• Quantity and unit (lengths, metres or kg).
• Grade (for example TP316L).
• Specification (for example ASTM A213) and seamless.
• OD and wall in mm, and minimum or average wall.
• Length and tolerance.
• Finish and delivery condition (for example bright annealed).
• Test and certificate requirements (for example EN 10204 3.1).
• Packing and destination.

ASTM, ASME and EN Standards for Stainless Steel Seamless Tubes

Standards play three roles. A product specification sets chemistry, manufacture, testing and tolerances. A dimensional standard fixes sizes and schedules. A general-requirements standard sets common rules that product specifications refer to. No single standard applies to every seamless tube, and tube and pipe specifications are not interchangeable. the current edition of each standard before publishing.

Tube Specifications

General-Requirements Standard for Tubes

ASTM A1016 sets general requirements for ferritic alloy, austenitic alloy and stainless steel tubes, and tube specifications refer to it for matters such as dimensional tolerances. An active edition (24a) was listed by ASTM at the time of writing. the edition and the exact reference from each tube specification.

Pipe Standards, for Comparison

Seamless Stainless Steel Tube vs Pipe

Both can be seamless, but they are different products. Pipe is sized by nominal pipe size (NPS) or DN and a schedule, and carries fluids in piping systems. Tube is sized by actual outside diameter and wall, and is used where dimensional control matters, as in heat exchangers, boilers and instrumentation. For pipe NPS 12 and smaller, the actual OD is larger than the size number; tube size equals the actual OD.

ASME B36.19M defines the stainless pipe schedules 5S, 10S, 40S and 80S, and the "S" suffix separates them from the carbon-steel schedules of B36.10M, whose wall thicknesses differ at some sizes. An order for stainless steel seamless pipes cites a pipe specification such as ASTM A312, while an order for tube cites one such as ASTM A213 or A269. Kamal Steels supplies both.

Stainless Steel Seamless Tube Manufacturing Process

A solid stainless steel billet is heated and pierced or extruded into a hollow shell, then elongated by hot rolling or extrusion. For cold-finished tube, the hollow is further reduced by cold drawing or cold pilgering. The tube is then solution annealed and pickled or otherwise finished to the delivery condition, straightened, cut to length, end-finished and marked. which of these steps Kamal Steels carries out itself and which are done by partner mills.

Seamless vs Welded Stainless Steel Tubes

Seamless tube has no longitudinal seam. Welded tube is formed from strip and joined along a seam, and may be cold worked afterwards. Seamless is often selected for critical, high-pressure or high-temperature service, and welded for cost-sensitive or large-volume requirements. A seamless tube is not automatically stronger than every welded tube: capacity depends on grade, wall thickness, manufacturing quality and the design code, and some codes apply a joint quality factor to welded product. Choose against the service conditions and the code your project follows.

Industrial Applications of Stainless Steel Tubing

• Heat exchangers and condensers: 304L, 316L, duplex and super duplex tube, often under ASTM A213 or A789.
• Boilers and superheaters: A213 tube in stabilised and H grades such as 321H and 347H.
• Chemical and petrochemical plants: 316L, 317L and 904L for corrosive process streams.
• Oil and gas and offshore: duplex and super duplex for chloride-bearing service.
• Instrumentation and general service: tubing to ASTM A269 where specified.
• Pharmaceutical, food and beverage: 304L and 316L where cleanliness and finish matter.

Stainless Steel Seamless Tube Testing and Quality Inspection

Buyers should specify the checks they need on the purchase order. The items below are commonly requested for seamless stainless steel tube. which Kamal Steels performs in-house, which are done by the mill and which by an outside laboratory.

• Material identification: heat number, grade, specification and size marked on each length or bundle, with positive material identification (PMI) on request.
• Dimensional and visual checks: outside diameter, wall thickness, length, straightness and surface condition against the order and the specification's tolerances.
• Specification tests: depending on the standard and the order, a hydrostatic or non-destructive electric test, flattening and flaring tests, tensile and hardness tests, and an intergranular corrosion test (for example ASTM A262) or duplex phase checks where specified.
• Traceability: the heat number on the product links it to the chemical and mechanical results on the certificate.

Material Test Certificates and Documentation

A Material Test Certificate (MTC) records the heat number, chemical analysis, mechanical test results and the specification the material was supplied to. EN 10204 type 3.1 is issued by the manufacturer and validated by a representative independent of production; type 3.2 adds validation by a purchaser-appointed or authorised inspector. Say which type you need when you enquire. EN 10204 3.1 as standard, and whether Kamal Steels arranges third-party inspection on request.

Stainless Steel Tube Packaging, Marking and Export

Stainless steel tube needs protection from damage and from iron contamination in handling. The practices below are typical for export consignments. Kamal Steels' standard method and options.

• End caps: to keep out dirt and protect tube ends.
• Bundling: with straps, or packing in wooden cases or on pallets for export, using treated wood where the destination requires it.
• Protective wrapping: waterproof or polyethylene wrapping for surface protection, especially for bright annealed and polished tube.
• Separation from carbon steel: with non-metallic slings or protected contact points.
• Marking: grade, specification, OD and wall, heat number, length and order reference on the product and the package.
• Transport: secure loading in container or truck to prevent movement and surface damage.

Kamal Steels – Stainless Steel Tube Manufacturer and Stockist

Kamal Steels works as a manufacturer and stockist of stainless steel seamless tubes and pipes from Mumbai. the exact basis of that description, which sizes are held in stock and which are made to order, lead times, minimum order quantity and export markets served. Standard items and made-to-order requirements are handled differently, so say in your enquiry which you need.

Stainless Steel Seamless Tube Price and Quotation Process

To help us understand your requirement and check the applicable product details, include the following information in your enquiry:

• Grade and UNS or EN designation.
• Product specification (for example ASTM A213, A269, A789 or EN 10216-5).
• OD and wall thickness in mm, minimum or average wall, and length.
• Finish and delivery condition.
• Quantity and delivery location.
• Test and certificate requirements, such as EN 10204 3.1 or 3.2.
• Packing requirements, especially for export.

Frequently Asked Questions About Stainless Steel Seamless Tubes

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