Carbon Steel Threadolet | NPT & BSPT Branch Outlets

Carbon Steel Threadolets Manufacturer and Supplier in India

A Carbon Steel Threadolet is a small bore branch outlet fitting that provides a female threaded outlet for the branch while allowing the branch to remain unfused to the main pipe. The base is contour bevelled and welded to the run and the outlet can be threaded with NPT, BSP or BSPT. Threadolets are required in cases where the branch needs to be removed, field welding is limited, or the connection is used to power an instrument, vent or drain that is being disconnected for maintenance. They are manufactured to MSS SP-97 and are rated Class 3000 for Schedule 80 branch pipe and Class 6000 for Schedule 160, for service in ASTM A105, Standard temperature. Solitaire Overseas provides threadolets in outlet sizes ranging from 1/8 in to 4 in and are provided with EN 10204 3.1 mill test certification and complete heat traceability.

Technical Data

Specifications Chemical Composition Mechanical Properties Dimensions Chart

Specifications of Carbon Steel Threadolets

Specification Parameter	Technical Details
Product Name	Carbon Steel Threadolet (Threaded Branch Outlet Fitting)
Material Grade	Forged Carbon Steel ASTM A105 / ASME SA105 / A105N (Normalized)
Governing Standards	• MSS SP-97: Integrally Reinforced Forged Branch Outlet Fittings • ASME B16.11: Forged Fittings, Socket-Welding and Threaded • ASME B1.20.1 / BS 21: Pipe Threads (NPT, BSP, BSPT)
Branch Size Range (Outlet)	1/8″ to 4″ NB (DN6 to DN100)
Run Pipe Size Range (Header)	1/4″ to 36″ NB (DN8 to DN900); customized up to 60″
End Connection Types	• Run End: Contour-beveled weld-on base • Outlet End: Female Threaded (NPT, BSP, BSPT)
Thread Profiles	NPT (National Pipe Taper), BSP (British Standard Pipe), BSPT (Tapered)
Manufacturing Process	Forged / Hot Rolled
Surface Treatments & Finish	Black Anti-Rust Oil, Paint Coating, Zinc Plating / Galvanized, Color Coated
Quality & NDT Inspection	Visual Inspection, Hardness Testing, Tensile Testing, Impact Testing, Material Identification (PMI)
Documentation & Reports	Mill Test Certificates (MTC per EN 10204 3.1), Heat Treatment Charts, Raw Material Test Reports

Chemical Compositions of Carbon Steel Threadolets

ELEMENT	COMPOSITION (%)
Carbon (C)	0.35 max
Manganese (Mn)	0.60 to 1.05
Phosphorus (P)	0.035 max
Sulfur (S)	0.040 max
Silicon (Si)	0.10 to 0.35
Chromium (Cr)	0.30 max
Nickel (Ni)	0.40 max
Molybdenum (Mo)	0.12 max
Copper (Cu)	0.40 max
Vanadium (V)	0.08 max

ASTM A105 Carbon Steel Threadolets Mechanical Properties

Property	Requirement
Tensile Strength (Min.)	485 MPa (70,000 psi)
Yield Strength (Min.)	250 MPa (36,000 psi)
Elongation (Min.)	22%
Reduction of Area (Min.)	30%
Hardness (Max.)	187 HB

Dimensions Chart of Carbon Steel Threadolets

Nominal Size (NPS)	Dimension C (in)	Dimension A (in)	Dimension B (in)
1/2″	15/16″	1″	1-13/32″
3/4″	1-5/32″	1-1/16″	1-23/32″
1″	1-7/16″	1-5/16″	2″
1-1/4″	1-3/4″	1-5/16″	2-9/16″
1-1/2″	2″	1-3/8″	2-27/32″
2″	2-9/16″	1-1/2″	3-15/32″
2-1/2″	3″	1-13/16″	4-1/16″
3″	3-11/16″	2″	4-13/16″
3-1/2″	4″	2-1/8″	5-7/32″
4″	4-3/4″	2-1/4″	5-31/32″
5″	5-9/16″	2-5/8″	7-5/16″
6″	6-11/16″	2-3/4″	8-5/8″

Applications and Industrial Uses of Carbon Steel Threadolets

Oil & Gas Industry
Petrochemical Industry
Chemical Processing Industry
Power Generation Industry
Refining Industry
Water Treatment Industry
Fertilizer Industry
Marine & Shipbuilding Industry

Frequently Asked Questions

What is a Carbon Steel Threadolet?

A Carbon Steel Threadolet is a forged branch outlet fitting with a threaded connection. It is used to connect a smaller branch pipe to a main pipe without a butt-welded branch connection.

Are Threadolets suitable for high-pressure applications?

Yes, Threadolets can be used for high-pressure applications when the correct pressure class, material grade, and design requirements are selected.

Can Threadolets be used for branch connections?

Yes. Threadolets are specifically designed for making threaded branch connections from a main pipe or header.

When should you use a Threadolet instead of a Weldolet?

Use a Threadolet when a threaded branch connection is preferred, especially for smaller branch sizes. A Weldolet is preferred when a butt-welded connection is required.

Can Carbon Steel Threadolets be used in oil and gas piping?

Yes, Carbon Steel Threadolets are commonly used in oil and gas piping for threaded branch connections, provided the material and pressure rating meet the project requirements.

Are Threadolets suitable for small-bore piping?

Yes. Threadolets are particularly suitable for small-bore branch piping where a threaded connection is preferred.

When is a Threadolet not the right choice?

A Threadolet may not be suitable for high-pressure or hydrocarbon service because threaded joints can create leak paths and cannot be radiographed. If threads are prohibited, use a Sockolet for socket-weld connections or a Weldolet for fully welded connections.