Welded Tubes supplied by NESCO Pipe & Tubes
Product formTubes
/ 01 — TECHNICAL OVERVIEW

Welded Tubes

Welded tubing provides a versatile and economical format for heat-transfer, process, structural and hygienic duties. Weld condition, bead treatment, heat treatment and inspection should be selected for the intended application.

Stainless steel tubes are manufactured for close dimensional tolerances, controlled surface finish and demanding service conditions. Depending on the application, tubes may be supplied in seamless or welded construction with annealed and pickled (AP), bright annealed (BA), polished or project-specific finishes.

Tubes are specified by actual outside diameter and wall thickness and are widely used where precision, cleanliness, corrosion resistance, heat transfer or reliable small-bore routing is critical.

Whether the requirement is for maintenance quantities or a project package, NESCO reviews the material, dimensions, specification, service conditions, inspection scope and delivery plan as one complete enquiry.

How it is made
01

Qualified strip or coil is slit to width and continuously formed into a tubular profile.

02

The longitudinal seam is welded under a controlled procedure and the bead is worked or removed when specified.

03

Cold working and solution heat treatment are applied where the ordered standard or service requires them.

04

The tube is sized, straightened, cut and finished to the agreed OD, wall, length and surface condition.

05

The weld, dimensions and pressure boundary are verified by the specified visual, eddy-current, hydrostatic or pneumatic tests.

Request reviewed quotation Material documents on request
/ 02 — PRODUCT DETAIL

Built around the specification.

Key characteristics and commonly referenced standards from the supplied technical content master.

Key features
01

Broad production range

02

Consistent OD and surface finish

03

Weld bead worked or removed where specified

04

Eddy-current, hydrostatic or pneumatic testing as required

Common specification references
STD

ASTM A269 for general-service stainless tubing

STD

ASTM A249 for welded boiler and heat-exchanger tubes

STD

ASTM A789 for duplex tubing

STD

Applicable material-specific standards

/ PRODUCT RANGE

Tube formats matched to the duty.

NESCO reviews construction route, service conditions, finish and inspection requirements before confirming the appropriate tube supply.

01

Seamless Tubes

Manufactured without a longitudinal weld seam for pressure, temperature and specification-defined critical service.

02

Welded Tubes

Produced from formed strip or coil with a controlled longitudinal weld, supporting dimensional consistency and commercial efficiency.

03

Heat Exchanger Tubes

Designed for heat transfer in condensers, shell-and-tube exchangers, coolers, evaporators and process equipment.

04

Boiler Tubes

Specified for elevated-temperature and pressure service in boilers, superheaters, reheaters and steam-generating equipment.

05

Instrumentation Tubes

Precision tubing with controlled OD, wall, hardness and surface for instrumentation, hydraulic and pneumatic systems.

06

Hydraulic Tubes

Precision tubing for high-pressure hydraulic-fluid transfer, subject to the approved material, dimensional and system specification.

07

Bright Annealed Tubes

Tubes heat treated in a controlled atmosphere to provide a smooth, clean and bright finish for hygienic and high-cleanliness duties.

/ 03 — MATERIAL RANGE

Grades matched to the service.

Commonly requested families are shown below. Availability is confirmed against the complete specification.

Material familyCommon gradesTypical selection context
Austenitic stainlessTP304/304L, TP316/316L, TP321, TP347/347H

General corrosion, process and elevated-temperature duties

Duplex stainlessS31803/S32205, S32750/S32760

Higher strength and chloride-bearing environments

High-alloy stainless904L, S31254

Selected acid and high-chloride services

Nickel alloysN06625, N08825, N10276 and others

Severe corrosion and high-temperature projects

Titanium / Cu-NiGrade 2, C70600, C71500

Seawater, condenser and selected chemical systems

/ 04 — SUPPLY & CUSTOMISATION

Define the supply condition.

Final availability depends on the complete combination of material, dimensions, standard, condition, testing and quantity.

ParameterTypical information to specify
01Product standard

ASTM A249 / A269 as applicable; dimensional tolerances to the ordered standard or approved project drawing

02Manufacturing type

Strip or coil formed and longitudinally welded under a controlled procedure

03Typical NESCO enquiry range

1/4 in. OD to 6 in. OD; larger or alternative dimensions reviewed against grade and standard

04Wall thickness

As specified; weld bead worked or removed where required and permitted

05Length

Straight or fixed cut length

06Ends

Square cut and deburred; capped or specially prepared on request

07Surface finish

Pickled and passivated, bright annealed or polished as specified

08Marking

Standard mill marking or agreed customer-specific identification

09Packaging

Sleeved or bundled, end protected, boxed or export packed as required

SURFACE CONDITION

Finish selected around cleanliness and service.

Availability and final acceptance depend on the manufacturing standard, material, size and agreed surface requirement.

01

Annealed & Pickled (AP)

Heat treated and acid cleaned; a common finish for general process tubing.

02

Bright Annealed (BA)

Controlled-atmosphere annealing produces a smooth, bright and oxide-free surface for precision or hygienic duty.

03

Polished

Mechanically finished to an agreed grit or roughness where appearance, cleanability or surface control is important.

04

Mill Finish

As-produced surface without additional pickling or polishing, used only where permitted by the product specification and application.

/ 05 — DIMENSIONS & SIZE RANGE

Dimensions aligned to the manufacturing route.

Tube is normally ordered by actual outside diameter and wall thickness. State whether wall is nominal or minimum and include the required tolerance.

Tube requirementTypical optionsWhat to specifyControl point
Outside diameterPrecision OD in metric or inchExact OD and toleranceFitting, tube-sheet or fabrication fit
Wall thicknessNominal or minimum wallWall and permitted variationPressure, heat transfer and forming
Length / formStraight, fixed length, coil or U-bendLength, radius and developed geometryEquipment fit-up
Surface / endsBA, AP, polished; cut/deburred/cappedInternal and external finishCleanliness and sealing
/ 06 — MANUFACTURING STANDARDS

Standards aligned for every order.

The material standard, dimensional standard and project requirements should be stated separately.

Stainless and duplex tube standards

StandardWhat it covers
ASTM A213/A213MSeamless ferritic and austenitic alloy-steel boiler, superheater and heat-exchanger tubes
ASTM A249/A249MWelded austenitic steel boiler, superheater, heat-exchanger and condenser tubes
ASTM A269/A269MSeamless and welded austenitic stainless tubing for general service
ASTM A789/A789MSeamless and welded ferritic/austenitic stainless tubing for general service
ASTM A270/A270MSeamless and welded stainless sanitary tubing for hygienic service
ASTM A554Welded stainless steel mechanical tubing for ornamental, structural and other mechanical applications
EN 10216-5 / EN 10217-7Seamless / welded stainless tubes for pressure purposes

Nickel-alloy tube standards

StandardWhat it covers
ASTM B163Seamless nickel and nickel-alloy condenser and heat-exchanger tubes
ASTM B407Nickel-iron-chromium alloy seamless pipe and tube
ASTM B444Nickel-chromium-molybdenum-niobium and related alloy seamless pipe and tube
ASTM B622Seamless nickel and nickel-cobalt alloy pipe and tube
/ TUBE SELECTION GUIDE

A practical starting point for specification review.

These references guide the enquiry only. The equipment design, material grade, service conditions and approved project specification govern the final selection.

ApplicationCommon specification basis
Heat exchangerASTM A213 seamless or ASTM A249 welded, as required by the equipment specification
Boiler / superheaterASTM A213 seamless or ASTM A249 welded, subject to the grade and design specification
Instrumentation / general serviceASTM A269 or the approved project tubing specification
Sanitary / hygienicASTM A270 with the required internal and external surface finish
HydraulicPrecision hydraulic-tube or project-specific specification matched to pressure, fluid and fitting system
Mechanical / decorativeASTM A554 with the required shape, finish and dimensional tolerances
CONSTRUCTION COMPARISON

Seamless and welded tubes, compared responsibly.

FeatureSeamlessWelded
Manufacturing routePierced or extruded from solid feedstockFormed from strip or coil and longitudinally welded
Longitudinal weldNonePresent and examined as required by the ordered standard
Typical selectionFrequently specified for critical pressure, thermal or mechanical dutyWidely used for heat-transfer, process, hygienic, structural and mechanical duty
Dimensional / surface controlCold finishing can provide close OD, wall and surface controlContinuous forming can provide consistent OD and surface finish
Commercial basisOften higher cost; depends on grade, size and routeOften more economical; depends on grade, size, testing and finish
Design ratingGoverned by the applicable code, material standard, dimensions and service conditionsGoverned by the applicable code, material standard, dimensions, weld quality and service conditions
/ 06 — REFERENCE MATERIAL DATA

Reference material data.

Representative values for frequently requested stainless grades. Values are percentages by mass or minimum mechanical requirements unless shown otherwise; always verify the ordered material standard, product form and edition.

Chemical compositionSelected principal elements · % max or range
GradeCCrNiOther
TP304L≤0.03518.0–20.08.0–13.0
TP316L≤0.03516.0–18.010.0–15.0Mo 2.0–3.0
TP321≤0.08017.0–19.09.0–12.0Ti: 5×(C+N) min–0.70
TP347≤0.08017.0–20.09.0–13.0Nb+Ta: 10×C min–1.00
Mechanical propertiesRoom-temperature minimums · verify the ordered product standard
GradeTensile MPaYield MPaElongation %
TP304L48517035
TP316L48517035
TP32151520535
TP34751520535
/ 07 — INSPECTION & TESTING

Evidence before dispatch.

01Material test certificate review and heat-number traceability
02Visual, dimensional, OD, wall-thickness and length checks
03Hydrostatic test or permitted nondestructive electric test, as specified
04Positive Material Identification (PMI) when requested
05Ultrasonic, eddy-current or other NDT to the purchase specification
06Intergranular corrosion, hardness, flattening or supplementary tests where applicable
07Third-party inspection coordination against an approved inspection plan
PACKAGING & MARKING

Protected and traceable.

01Heat-wise bundles with durable material and purchase-order identification
02Plain or prepared ends protected with plastic end caps where applicable
03Sleeves, waterproof wrapping, boxes or wooden export crates selected for the tube form and transport route
04Straight lengths and coils restrained to prevent movement, surface damage and contamination
05Heat number, batch, grade, OD, wall, length and standard retained on package identification
06Customer-specific marking and packing can be reviewed before order placement
/ 08 — APPLICATIONS & INDUSTRIES

Engineered for demanding service environments.

From process plants to marine systems, NESCO coordinates material, dimensions and documentation around the operating conditions of each application.

01
Shell-and-tube heat exchangers
02
Boilers and steam generators
03
Condensers and coolers
04
Instrumentation and control systems
05
Chemical dosing and sampling
06
Hydraulic and pneumatic lines
07
Food and pharmaceutical process systems
08
Semiconductor and high-cleanliness systems
09
Dairy and biotechnology equipment
10
HVAC and refrigeration
11
Automotive and general engineering
Industries servedOne supply partner across critical sectors.
Oil & gasPetrochemicalsChemical processingPower generationMarine & offshoreWater & desalinationFood & pharmaceuticalsGeneral engineering
/ 09 — WHY NESCO PIPE & TUBES

Built for buyers who cannot leave details to chance.

From specification review to export documentation, NESCO coordinates the technical and commercial details as one complete supply requirement.

01

Specification control

NESCO reviews the grade, product standard, dimensions, condition and acceptance criteria as one coordinated requirement.

02

Multi-material sourcing

Stainless steel, duplex, nickel alloy, copper-nickel and titanium requirements can be combined within one project enquiry.

03

Traceable documentation

Heat numbers, MTCs and agreed inspection records are aligned with the purchase order before dispatch.

04

Inspection coordination

PMI, dimensional checks, NDT and third-party witnessing can be arranged against an approved inspection plan.

05

Value-added processing

Cutting, machining, end preparation, polishing or protective finishing can be reviewed with the base material supply.

06

Export-ready packing

Identification, surface protection and packing are planned around product geometry and the final transport route.

07

Responsive RFQ review

Technical and commercial inputs are consolidated early so queries are resolved before quotation and production.

08

One accountable supply desk

NESCO provides a single contact for material, processing, documentation, packing and delivery coordination.

/ 10 — FREQUENTLY ASKED QUESTIONS

Clear answers before you specify.

Quick guidance on product selection, standards, dimensions, inspection and documentation. For project-specific requirements, NESCO will review the complete enquiry with your team.

01Can the internal weld bead be removed?

Bead working or removal may be specified depending on the standard, size and end use; state the required internal surface condition in the enquiry.

02How is the weld seam inspected?

Eddy-current, hydrostatic, pneumatic, ultrasonic or other methods may be used according to the product standard and purchase order.

03How is tube sizing different from pipe sizing?

Tube is normally ordered by actual outside diameter and wall thickness; pipe commonly uses NPS and schedule.

04When should I choose seamless tube?

It is commonly selected for demanding pressure, heat-transfer, instrumentation or mechanical duties where the project specification calls for a seamless route.

05Can NESCO supply heat-exchanger or U-bend tubes?

Straight and U-bend requirements can be reviewed against the grade, standard, OD, wall, developed length, bend radius and inspection scope.

06Which surface finishes are available?

Annealed and pickled, bright annealed, polished and project-specific finishes may be available depending on the manufacturing standard and size.

07What is the difference between tubes and pipes?

Tubes are normally ordered by actual outside diameter and wall thickness and are commonly used for precision, heat-transfer or instrumentation duty; pipes are commonly ordered by NPS and schedule for piping systems.

08What is the difference between seamless and welded tubes?

Seamless tube has no longitudinal weld; welded tube is formed from strip or coil and joined along a longitudinal seam. The correct route depends on the material standard, dimensions, service, inspection and project specification.

09Which standard is suitable for heat-exchanger tubes?

ASTM A213 for seamless and ASTM A249 for welded stainless tubing are common references. The exchanger design, material grade and project specification determine the correct standard.

10Which tube finish should I choose?

Annealed and pickled is common for general process duty, bright annealed for precision or hygienic duty, and polished finish where an agreed appearance or surface roughness is required.

11Can EN 10204 3.1 certification be supplied?

EN 10204 3.1 inspection certificates can be supplied when included in the quotation and purchase order. Third-party witnessed certification can be reviewed where the agreed inspection route supports it.

12Can tubes be supplied in coil form?

Coil supply may be available depending on the material, OD, wall thickness, condition and cleanliness requirement; larger or heavier tubing is generally supplied in straight lengths.

13Can third-party inspection be arranged?

Yes. Inspection by an agreed agency can be coordinated when the scope, hold points, document requirements and agency are confirmed before order placement.

14How do I request a quotation?

Use the product enquiry form and include the tube type, material grade, standard, OD, wall, length or coil geometry, quantity, testing, documentation and delivery destination.

/ 11 — REQUEST FOR QUOTATION Nesco direct sales desk
Selected productWelded Tubes

Turn your specification into a supply-ready enquiry.

Send your welded tubes specification, drawing or bill of materials for a grade-and-dimension-matched quotation.

Technical review Documentation support Email-ready submission
Ready to source?Start with the details you already have.

Our team will review the grade, dimensions, testing and delivery requirements together.