Name: Elbolet
Brand: Cunimet Alloy International

Product Overview

Elbolet

The Elbolet is a specialised integrally forged branch outlet fitting designed to be welded directly onto the body of a pipe elbow, rather than onto straight pipe. The base of the Elbolet is machined with a concave saddle curve that matches the outside diameter of the elbow at the point of installation, ensuring full contact and a consistent, gap-free weld preparation around the full circumference of the base weld.

Elbolets are typically installed on the extrados (outside radius) of a 90-degree elbow to create a branch connection at the elbow itself, eliminating the need for a separate straight pipe spool between the elbow and the branch point. This reduces the overall piping assembly length, lowers installation cost and removes one additional weld joint from the system.

Cunimet Alloy International manufactures Elbolets in three end connection types to suit all piping systems: butt weld (BW), socket weld (SW) and threaded (NPT). The fitting is available in standard elbow sizes from 2" to 16" NPS run, with branch sizes from 1/2" to 4" NPS. All are manufactured per MSS SP-97 in the standard material grades.

MSS SP-97 ASTM A182 Run Elbow: 2"–16" NPS Branch: 1/2"–4" NPS BW • SW • Threaded

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MSS Standard SP-97

BW/SW/THD End Connections All Three Types

2–16" Elbow Run Size NPS

1/2–4" Branch Size NPS

3 Material Grades SS / Duplex / S.Duplex

End Connection Options

Three End Connection Types Available

Butt Weld (BW)

The BW Elbolet has a bevelled butt weld end at the branch outlet. The branch pipe is joined using a full-penetration groove weld. Recommended for large-bore branches (1" and above) and for piping systems subject to volumetric NDE examination of the branch joint.

ASME B16.25 Bevel Full Penetration Weld Branch 1/2"–4" NPS

Socket Weld (SW)

The SW Elbolet carries a precision-bored socket at the branch outlet per ASME B16.11. The branch pipe is inserted into the socket and secured with a fillet weld. Preferred for small-bore branches in high-pressure socket weld piping systems where a simpler fillet weld joint is acceptable.

ASME B16.11 Socket Fillet Weld Joint Branch 1/2"–4" NPS

Threaded (NPT)

The threaded Elbolet carries a female NPT thread at the branch outlet per ASME B1.20.1. Allows a screwed pipe, valve or instrument to be connected to the elbow branch point without welding the branch connection. Preferred for instrument tapping and drain points on elbows.

ASME B1.20.1 NPT Screwed Connection Branch 1/2"–2" NPS

Technical Dimensions

Elbolet — MSS SP-97 Branch Dimensions

“H” = Overall height from the elbow OD contact surface to the top face of the branch outlet. The base radius is machined to match the specific elbow OD (which varies by elbow NPS and schedule). Specify elbow NPS and schedule when ordering. All dimensions in millimetres.

Branch NPS	Branch Pipe O.D. (mm)	Height “H” by End Connection (mm)
Branch NPS	Branch Pipe O.D. (mm)	Butt Weld (BW)	Socket Weld (SW)	Threaded (NPT)
1/2"	21.3	70	60	64
3/4"	26.7	76	67	70
1"	33.4	83	76	79
1-1/4"	42.2	95	83	89
1-1/2"	48.3	102	89	95
2"	60.3	121	108	114
2-1/2"	73.0	140	127	133
3"	88.9	159	146	152
4"	114.3	191	178	—

Heights are nominal per MSS SP-97. Base saddle curve is machined to specific elbow OD. Please state elbow NPS, schedule and material when ordering. Threaded end not available for 4" NPS. All dimensions in millimetres.

Standard Elbow Compatibility

The following shows the standard run elbow sizes on which Elbolets are typically installed. Always specify the elbow NPS and schedule to ensure the correct base curve.

Elbow NPS (Run)	Elbow O.D. (mm)	Standard Branch Sizes Available (NPS)	Elbow Schedule / Wall
2"	60.3	1/2", 3/4", 1"	Sch 40 / Sch 80 / XH
3"	88.9	1/2", 3/4", 1", 1-1/2", 2"	Sch 40 / Sch 80 / XH
4"	114.3	1/2" through 2-1/2"	Sch 40 / Sch 80 / XH
6"	168.3	1/2" through 3"	Sch 40 / Sch 80 / XH
8"	219.1	1/2" through 4"	Sch 40 / Sch 80 / XH / Sch 120
10"	273.1	1/2" through 4"	Sch 40 / Sch 60 / Sch 80 / XH
12"	323.8	1/2" through 4"	Sch 40 / Sch 80 / XH
14" & 16"	355.6 / 406.4	1/2" through 4"	Sch 40 / XH / Custom

Available Materials

Material Grades for Elbolets

Grade 01

Stainless Steel 304 / 316

Austenitic stainless steel Elbolets for chemical, pharmaceutical and food industry piping elbows where branch connections are required at elbow locations. SS 316 is the standard for offshore, marine and chloride-bearing environments.

ASTM A182 F304 ASTM A182 F316 MSS SP-97

Grade 02

Duplex Steel

High-strength duplex Elbolets for offshore topside piping elbows and chemical plant process lines where the elbow location requires a branch connection in a corrosion-resistant, high-strength alloy to match the surrounding piping material.

ASTM A182 F51 UNS S31803 UNS S32205

Grade 03

Super Duplex Steel

Premium super duplex Elbolets with PREN greater than 40 for seawater service piping elbows, offshore subsea systems and desalination plant piping where maximum corrosion resistance is required at the elbow branch connection point.

ASTM A182 F53 UNS S32750 UNS S32760

Quality & Compliance

Standards, Testing & Documentation

Applicable Standards

Standard	Description
MSS SP-97	Integrally Reinforced Forged Branch Outlet Fittings — primary standard
ASTM A182	Material specification for forged alloy and stainless steel fittings
ASME B16.25	Butt Welding Ends (for BW end Elbolets)
ASME B16.11	Socket weld bore dimensions (for SW end Elbolets)
ASME B1.20.1	NPT thread form and tolerances (for threaded end Elbolets)
EN 10204	3.1 MTC standard; 3.2 with TPI on request

Quality Tests Performed

Test	Method / Scope
Chemical Analysis	OES per ASTM A182 for each heat of material
Mechanical Testing	Tensile, yield, elongation and Charpy impact where specified
Hardness Testing	Brinell or Vickers per ASTM A182 requirements
PMI	100% XRF Positive Material Identification on request
Dimensional Inspection	Height, OD, bore/socket/thread and base contour radius
Visual & NDE	Visual per MSS SP-55; PT/MT on request

Applications

Where Elbolets Are Used

01

Compact Elbow Branch Points

Installing a branch at an elbow location in congested process plant areas where there is insufficient straight pipe between the elbow and the required branch tapping point to use a standard Weldolet or Sockolet.

02

Drain & Vent on Elbows

Adding drain valves or vent connections directly at elbow bends in process piping headers, steam distribution systems and cooling water circuits where draining at the lowest point occurs at an elbow location.

03

Instrument Connections on Elbows

Welding threaded Elbolets on pipeline elbows to create NPT tapping points for pressure gauges, temperature transmitters and flow measurement instruments at elbow locations where the flow regime is suitable for measurement.

04

Offshore & Subsea Piping

Creating compact branch connections at elbow locations on offshore topside piping in Duplex and Super Duplex Steel, where the compact geometry of the Elbolet reduces the overall piping envelope in congested module areas.

Branch Outlets Range

Elbolet — Branch Outlet for Elbows