Defense Market

Tubing and Engineered Shapes for Defense

Drawing on over 100 years of manufacturing excellence, Plymouth® serves as a strategic partner to the defense industry, providing mission-critical solutions for land, sea, and air platforms. We address the rigorous needs of the defense market by delivering high-performance specialty tubing, precision extrusions, and advanced laminations that prioritize structural integrity, weight reduction, and superior protection.

Our products are engineered to excel in high-threat environments, ranging from aircraft-quality tubing for aerospace structures to custom hot-extruded profiles for naval frigates, submarines, and armored vehicles. By integrating our U.S.-based metallurgical production with specialized international finishing and lamination capabilities at Plymouth Schwerter Technik, we provide a unified global supply chain that meets the strictest military specifications for ballistic integrity and operational readiness.

Defense

Tubing and Engineered Shapes for Defense

Drawing on over 100 years of manufacturing excellence, Plymouth® serves as a strategic partner to the defense industry, providing mission-critical solutions for land, sea, and air platforms. We address the rigorous needs of the defense market by delivering high-performance specialty tubing, precision extrusions, and advanced laminations that prioritize structural integrity, weight reduction, and superior protection.

Our products are engineered to excel in high-threat environments, ranging from aircraft-quality tubing for aerospace structures to custom hot-extruded profiles for naval frigates, submarines, and armored vehicles. By integrating our U.S.-based metallurgical production with specialized international finishing and lamination capabilities at Plymouth Schwerter Technik, we provide a unified global supply chain that meets the strictest military specifications for ballistic integrity and operational readiness.

Defense Applications

  • Tactical and armored vehicle frames and substructures
  • Roll cages and occupant protection systems
  • Weapon system mounts
  • Platform components for missiles, launchers, and radar
  • Mobility platforms, trailers, and other transport systems
  • Aircraft and rotorcraft assemblies
  • Specialized protective and structural systems
  • Hydraulic and pneumatic lines
  • Weapon and recoil system components
  • Aircraft and UAV structures
  • Armor and mobility systems

Plymouth® Defense Products

To support the most demanding defense applications, we maintain a rigorous quality and compliance framework built on over 100 years of manufacturing excellence. Our mission-critical components are produced through high-precision processes—including hot extrusion, cold drawing, and specialized lamination—to ensure the highest structural and ballistic integrity. Every product is validated through a robust quality management system and advanced testing protocols, ensuring it meets or exceeds the strictest military and aerospace specifications, as shown here.

AS9100D 

The premier quality management system for the aerospace and defense industry

ISO 9001:2015

International standard ensuring consistent quality management across global facilities 

Nadcap Accredited 

Specialized accreditation for Material Testing (MTL) and Non-Destructive Testing (NDT) 

ITAR Compliant 

Registered to manufacture and protect sensitive defense-related technology and components 

PED 

Certified to produce pressure-containing equipment and systems 

REACH & RoHS

Compliance with global environmental safety and hazardous substance regulations 

ISO 14001 

Certification for robust and effective environmental management systems. 

Bundeswehr TL 

Adherence to German military technical supply conditions for theater-ready equipment.

Carbon DOM Tubing

Engineered for uncompromising resilience, Plymouth®’s carbon DOM tubing empowers defense contractors with superior weldability and structural integrity. It is the strategic choice for advanced ground systems and logistical transport, ensuring sustained field performance under extreme operational stress. Carbon DOM tubing’s defense applications include:

  • Hydraulic systems Suspension control arms
  • System mounting components
  • Tactical communication masts
  • Cargo and support systems
  • Tactical vehicle frames and sub-structures

ASTM A513-5: Carbon DOM Tubing Specifications

MeasurementInches/Feet Metric

 OD Range 

0.250” – 1.8750” 

6.35mm – 47.63mm 

Wall Range

0.025” – 0.125” 

0.635mm – 3.175mm 

Maximum Length 

26’ 

7.9 m

Industry Specifications

  • Carbon Grades: 1010 – 1020

Cold Drawn Seamless Steel Tubing

Seamless tubing is employed throughout the defense market due to its enhanced dimensional control and mechanical properties. The absence of any welding seams delivers higher fatigue resistance and structural integrity for high-stress systems.

ASTM A519: Cold Drawn Seamless Carbon & Alloy Steel Tubing

MeasurementInches/FeetMetric

OD Range

0.250” – 2” 

6.35mm – 50.8mm 

Wall Range 

0.025” – 0.187” 

0.635mm – 4.75mm 

Maximum Length 

26’ 

7.9m

Industry Specifications

  • Carbon Grades: 1010 – 1018
  • Alloy Grades: 4130, 4140

ProMoly®: Seamless 4130 Steel Tubing

Plymouth®’s ProMoly® seamless 4130 tubing offers the defense sector a high-strength, lightweight chromoly solution optimized for the fabrication of rugged tactical ground systems and transport architectures.

  • Tactical and armored vehicle frames and substructures
  • Roll cages and occupant protection systems
  • Weapon system mounts and support components
  • Platform components for missiles, launchers, and radar
  • Mobility platforms, trailers, and other transport systems

ProMoly® Seamless 4130 Steel Specifications

MeasurementInches/FeetMetric

OD Range

0.250” – 2.000”

6.35mm – 50.8mm 

Minimum OD Tolerance 

+/- 0.005” (up to 1.500” OD)

+/- 0.127mm (up to 38.1mm) 

Maximum OD Tolerance 

+/- 0.10” (above 1.500” OD) 

+/- 2.54mm (above 38.1mm) 

Wall Range 

0.025” – 0.187” 

0.635mm – 4.75mm 

Minimum Wall 

Tolerance +/- 10% (For IDs over 0.500”) 

+/- 10% (For IDs over 12.7mm) 

Maximum Wall Tolerance 

+/- 15% (for IDs under 0.500”) 

+/- 15% (for IDs under 12.7mm) 

Maximum Length 

26’ 

7.9m

Industry Specifications and Certifications

  • Grade: 4130
  • Industry Specifications: AMS-T-6736A | AMS-6371 | AMS-6360 | MIL-T-6736B
  • Certifications: ISO 9001

Cold Drawn Shapes

When failure is not an option in mission-critical environments, Plymouth®’s cold drawn shapes deliver the exact tolerances required for advanced tactical guidance and ballistic armor. We provide defense sectors with the structural integrity needed to support critical operational platforms worldwide, including:

  • Ballistic grilles and profiles
  • Tactical mounting systems
  • Armored vehicle components
  • Tactical hardware support systems
  • Missile launch and guidance supports

Cold Drawn Shape Specifications

Material Specifications

Carbon & Alloys

US Grades in Series 1000, 4000, 6000, 8000, 9000

Stainless Steel in Complex Geometries 

Series 300 & 400 Stainless Steel 

PH Grades in Rounds, Hexes or Octagons

17-4, 17-7, 15-5, 13-8 

Exotic Alloys 

Monel 400, Inconel, Hastelloy, etc.

Shape Specifications

Solid, Round 

0.2500” – 3.750” OD 

Hexagon and Octagons, across flats 

0.3125” – 3.625” 

Rectangles and Squares 

0.625” per side min, 5.000” max 

Unique Shapes 

Greater than 0.625” 

Profile must fit within 6.500” Diameter Circle

Dimensional Specifications

Dimensional Tolerance, Standard*

+/- 0.005” 

Fillet and Radii Tolerance, Standard* 

0.015” in Carbon, 0.360” in Stainless 

Ratio of Height vs. Width 

1 : 1.16 (Max.) 

Cross-Sectional Area 

0.125 sq. in. (Min.)

*Tighter Tolerances may be available

Stainless Steel & Carbon Steel Extrusions

Plymouth® extrusions provide the structural stability and high-tensile strength required to meet the rigorous safety and performance standards of the defense industry. Our large-scale manufacturing ensures consistent metallurgical integrity for mission-critical components, including:

  • Armored vehicle chassis rails
  • Weapon system mounts
  • Ballistic grilles and protective structures
  • Tactical hardware support components

Carbon Steel Extruded Engineered Shapes

Carbon & Alloy Steel Grades 

1018
1029
1030
1035
1040

1045
1050
1060
1215
4130 

4140
4150
4340
6150 

8620
8630
8640
9310 

A36
A588
A690
Grade 50
Grade 60

Industry Specifications 

AMS S6758
AMS 6415
AMS S5000 

ASTM A 36
ASTM A
105
ASTM A
322 

ASTM A
576
ASTM A
588
ASTM A
690 

AMS-S-6758A
AMS 6382

Outside Dimensions 

Shape cross-section must fit within 6” (152.4mm) diameter.

Stainless Steel Extruded Engineered Shapes

Stainless Steel Grades 

303
304 series
310
316 series

400 series
418
422

13-8 MO
15-5 PH
17-4
PH 17-7

Industry Specifications 

AMS 5610
AMS 5613
AMS 5616
AMS 5621
AMS 5627 

AMS 5629
AMS 5639
AMS 5640
AMS 5643
AMS 5645 

AMS 5646
AMS 5648
AMS 5651
AMS 5659
AMS QQS 763 

ASTM A 276
ASTM A 511

Outside Dimensions 

Shape cross-section must fit within 5.5” (139.7mm) diameter.

Titanium Extrusions

For defense applications requiring lightweight strength and durability, titanium extrusions are used in:

  • Structural vehicle components
  • Missile and weapons system supports
  • Aircraft and rotorcraft assemblies
  • Specialized protective and structural systems

Titanium Extrusion Specifications

Available Titanium Grades 

6AL-4V 

6AL-6V-2SN 

6AL-2SN-4ZR 2MO* 

Other grades available upon request.

Outside Dimensions 

Shape cross-section must fit within 7.75” (196.8mm) diameter 

*Shape cross-section must fit within 6” (152.4mm) diameter

Industry Specifications 

AMS 4935
AMS 4975

DMS 1650
AMS-T-81556A

AMS 4921
MS 1202

AIMS 03-18-011

Seamless Stainless Steel Tubing

Secure your defense supply chain with an ITAR-compliant leader in high-volume seamless stainless steel tubing. We strictly adhere to MIL-SPEC and AMS standards, leveraging our U.S. and global manufacturing capabilities to ensure absolute material consistency for critical military assets:

  • Naval infrastructure
  • Tactical aerospace
  • Strategic platforms
  • Propulsion and fluid systems

Seamless Stainless Aerospace Tubing Specifications

Aircraft SpecificationsGradesOD RangeWall RangeMaximum Length

AMS 5564, AMS 5565, AMS 5567, AMS 5569, MIL-T-5695 

304/L 

0.125” – 3.000” 3.175mm – 76.2mm 

0.016” – 0.218” 0.4064mm – 5.54mm 

48ft – 60ft
14.63m – 18.29m

AMS 5573, AMS 5584 1/8 hard 

316/L

0.125” – 3.000” 3.175mm – 76.2mm 

0.016” – 0.218” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

AMS 5557, AMS 5570, AMS 5896, AMS 5897 

321

0.125” – 3.000” 3.175mm – 76.2mm 

0.016” – 0.218” 0.4064mm – 5.54mm 

48ft – 60ft
14.63m – 18.29m

AMS 5557 

347 

0.125” – 3.000” 3.175mm – 76.2mm 

0.016” – 0.218” 0.4064mm – 5.54mm 

48ft – 60ft
14.63m – 18.29m

AMS 5581

625 

0.125” – 3.000” 3.175mm – 76.2mm 

0.016” – 0.218” 0.4064mm – 5.54mm 

48ft – 60ft
14.63m – 18.29m

Mechanical Properties

Tensile Strength

515 MPa minimum / 75,000 psi minimum 

Yield Strength

205 MPa minimum / 30,000 psi minimum 

Total Elongation Under Load 

30.000% 

Hardness 

22 Maximum HRC

Alloys

  • Austenitic: 304/L/N, 316/L/N, 317/L, 321, 347
  • Duplex/Lean Duplex: 2101, 2205, 2507
  • Nickel Alloy: 600, 625, 800, 825

Seamless Nickel Alloy Tubing

Plymouth® reinforces mission-critical systems with high-volume production of seamless nickel alloy tubing engineered for the most extreme thermal and corrosive environments. As an ITAR-compliant partner, we deliver the metallurgical stability and absolute consistency required for defense contracts. Our strategic global network provides the specialized material integrity necessary for:

  • Submarine and naval systems
  • High-temperature propulsion
  • Strategic power infrastructure
  • Advanced engine components

Seamless Nickel Alloy Aerospace Tubing Specifications

Aircraft SpecificationsGradesOD RangeWall RangeMaximum Length

AMS 5564, AMS 5565, AMS 5567, AMS 5569, MIL-T-5695

304/L 

0.125” – 3.000” 3.175mm – 76.2mm 

0.016” – 0.218” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

AMS 5573, AMS 5584 1/8 hard 

316/L 

0.125” – 3.000” 3.175mm – 76.2mm 

0.016” – 0.218” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

AMS 5557, AMS 5570, AMS 5896, AMS 5897 

321 

0.125” – 3.000” 3.175mm – 76.2mm 

0.016” – 0.218” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

AMS 5557 

347 

0.125” – 3.000” 3.175mm – 76.2mm 

0.016” – 0.218” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

AMS 5581

625 

0.125” – 3.000” 3.175mm – 76.2mm 

0.016” – 0.218” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

Welded Nickel Alloy Tubing

Plymouth®’s welded nickel alloy tubing provides exceptional high-temperature stability and corrosion resistance. Custom-engineered for strict MIL-SPEC and AMS compliance, it is an essential material solution for manufacturing defense systems and components:

  • Maritime fluid systems
  • Tactical propulsion
  • Strategic ground assets
  • Aerospace infrastructure

Welded & Drawn Nickel Alloy Aerospace Tubing Specifications

Aircraft SpecificationsGradesOD RangeWall RangeMaximum Length

AMS 5564, AMS 5565, AMS 5566, AMS 5567, AMS 5569 

304/L 

0.188” – 4.000” 4.78mm – 101.6mm 

0.016” – 0.218” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

AMS 5557, AMS 5575 

321 

0.188” – 4.000” 4.78mm – 101.6mm 

0.016” – 0.218” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

AMS 5556, AMS 5575 

347 

0.188” – 4.000” 4.78mm – 101.6mm 

0.016” – 0.218” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

AMS 5581 

625 

0.188” – 4.000” 4.78mm – 101.6mm 

0.016” – 0.141” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

AMS 5580, AMS 5581 

600 

0.188” – 4.000” 4.78mm – 101.6mm 

0.016” – 0.141” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

PWA 1065 

718 

0.188” – 4.000” 4.78mm – 101.6mm 

0.016” – 0.136” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

TP-716 

718 

0.188” – 4.000” 4.78mm – 101.6mm 

0.016” – 0.136” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

AMS 5561, BMS 7-185, HMS6-1132 

21-6-9 

0.188” – 4.000” 4.78mm – 101.6mm 

0.016” – 0.110” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

AMS 5568 

17-7PH® 

0.188” – 4.000” 4.78mm – 101.6mm 

0.016” – 0.136” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

AMS 5578 

Custom 455® 

0.188” – 4.000” 4.78mm – 101.6mm 

0.016” – 0.110” 0.4064mm – 5.54mm

48ft – 60ft 14.63m – 18.29m

17-7PH® is a registered trademark of AK Steel. Custom 455® is a registered trademark of Carpenter Technology.

Welded Stainless Steel Tubing

Plymouth® welded stainless steel tubing provides a versatile, high-integrity solution for military infrastructure requiring a balance of structural durability and field-proven reliability. Our ITAR-compliant manufacturing ensures the scalable production and material traceability necessary for mission-critical applications, including:

  • Hydraulic and fluid actuation lines
  • Vehicle structural frameworks
  • Naval support systems
  • Tactical equipment housing

Welded & Drawn Stainless Steel Aerospace Tubing Specifications

Aircraft SpecificationsGradesOD RangeWall RangeMaximum Length

AMS 5564, AMS 5565, AMS 5566, AMS 5567, AMS 5569 

304/L 

0.188” – 4.000” 4.78mm – 101.6mm 

0.016” – 0.218” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

AMS 5557, AMS 5575 

321 

0.188” – 4.000” 4.78mm – 101.6mm 

0.016” – 0.218” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

AMS 5556, AMS 5575 

347

0.188” – 4.000” 4.78mm – 101.6mm 

0.016” – 0.218” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

AMS 5581 

625 

0.188” – 4.000” 4.78mm – 101.6mm 

0.016” – 0.141” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

AMS 5580, AMS 5581 

600 

0.188” – 4.000” 4.78mm – 101.6mm 

0.016” – 0.141” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

PWA 1065 

718

0.188” – 4.000” 4.78mm – 101.6mm 

0.016” – 0.136” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

TP-716 

718 

0.188” – 4.000” 4.78mm – 101.6mm 

0.016” – 0.136” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

AMS 5561, BMS 7-185, HMS6-1132 

21-6-9 

0.188” – 4.000” 4.78mm – 101.6mm 

0.016” – 0.110” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

AMS 5568 

17-7PH® 

0.188” – 4.000” 4.78mm – 101.6mm 

0.016” – 0.136” 0.4064mm – 5.54mm 

48ft – 60ft 14.63m – 18.29m

AMS 5578 

Custom 455® 

0.188” – 4.000” 4.78mm – 101.6mm 

0.016” – 0.110” 0.4064mm – 5.54mm

48ft – 60ft 14.63m – 18.29m

Mechanical Properties

Tensile Strength 

515 MPa minimum / 75,000 psi minimum 

Yield Strength

205 MPa minimum / 30,000 psi minimum 

Total Elongation Under Load 

30.000% 

Hardness 

22 Maximum HRC

Alloys

  • Austenitic: 304/L/N, 316/L/N, 317/L, 321, 347
  • Ferritic/Super-Ferritic: 430, 439
  • Duplex/Lean Duplex: 2101, 2205, 2507
  • High Nickel: AL-6XN®, 600, 625, 800, 825, C-276, C-22
  • PH Grades: 17-4, 17-7
  • Specialty: E-Brite®, Nitronic 30/40, Alloy 20, Invar 36, 718, 21-6-9

Downloads & Resources

FileLanguageSizeDownload
ProMoly® BrochureEN3 MB Download
Streamline TubingEN144 KB Download
Stainless Steel Tubing: Austenitic, Ferritic & DuplexEN676 KB Download
Streamline TubingEN144 KB Download
Extruded Engineered Shapes and Cold Drawn ShapesEN406 KB Download
Precision Cold Drawn Net ShapesEN256 KB Download
Aerospace Shapes BrochureEN399 KB Download
Plymouth Heat Exchanger TubingEN419 KB Download
Selecting Tubing Materials for Power Generation Heat ExchangersEN265 KB Download
Plymouth® Product CatalogEN4 MB Download
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