Carbon Steel Nippolets | Instrument Standoff Outlets

Carbon Steel Nippolets are forged branch outlet fittings that join smaller branch pipes to main pipelines with a reliable pressure integrity. These are typically produced from carbon steel grades like ASTM A105 and supplied with socket weld, threaded or butt weld outlet end are generally delivered per MSS SP-97. A105 forging gives a minimum tensile strength of 485 MPa (70 ksi) and a minimum yield of 250 MPa (36 ksi), with hardness controlled to 187 HB maximum. The Carbon Steel Nippolets are used in the oil and gas, petrochemical, power generation, refineries and process industry sectors. Solitaire Overseas is a reputed manufacturer and supplier of Carbon Steel Nippolets in India, known for supplying precision forged fittings in various sizes, pressure classes, dimensions and end connections to cater to the international piping requirements. The nipple extension makes a nippolet different from a sockolet or threadolet since it supplies the necessary standoff for a pressure gauge, thermowell or instrument tapping without an additional nipple and connection. The usual standoff varies between 89 mm and 165 mm, with extended models meeting the standards for the use of instrument.

Technical Data

Specifications Chemical Composition Mechanical Properties Dimensions Chart Wall Thickness Chart

Specifications of Carbon Steel Nippolets

Specification	Technical Details & Standard Compliance
Product Name	Carbon Steel Nippolets (Nipple Outlets)
Material Grades	Standard CS: ASTM A105 / A105N (Normalized) Low-Temp CS: ASTM A350 LF2 Class 1 / Class 2 High-Yield CS: ASTM A694 (F42, F52, F60, F65, F70)
Design Standards	MSS SP-97: Integrally Reinforced Forged Branch Outlet Fittings (Socket Welding, Threaded, and Buttwelding Ends) ASME B16.11: Forged Fittings, Socket-Welding and Threaded BS 3799: Screwed and Socket-Welding Fittings for Petrochemical Duty
Thread & Welding Standards	Threads: ASME B1.20.1 (NPT), BS 21 / ISO 7-1 (BSPT) Welding Ends: ASME B16.25 (Buttweld / Beveled), ASME B16.11 (Socket Weld)
Pressure Class & Schedules	Pressure Rating: Class 3000 LBS, Class 6000 LBS Schedule Ratings: Schedule 80 / XS, Schedule 160, Schedule XXS
Outlet Size Range	1/4" NB to 4" NB (DN15 to DN50) standard; up to 4" NB (DN100) available on request
Run Pipe Size Range (Header)	1/2" NB to 24" NB (DN15 to DN600) and flat runs for larger header diameters
Nipple Length / Standoff	Standard Length: 3.5" to 6.5" (89 mm to 165 mm) Custom Lengths: Extended lengths manufactured to project-specific instrument standoff dimensions
Outlet End Connections	Plain End (PE), Beveled End (BE), Threaded End (Male NPT / BSPT), Socket Weld (SW)
Manufacturing Process	Solid Forged, Precision CNC Machined, Heat Treated (Normalized for A105N / LF2)
Quality & Testing	PMI (Positive Material Identification), Hydrostatic Test, Ultrasonic / Radiographic Testing, Hardness Testing, NACE MR0175 / ISO 15156 (Sour Service Compliance)
Certifications	EN 10204 3.1 Mill Test Certificate (MTC), NACE MR0175 / MR0103 Certificate, EN 10204 3.2 Third-Party Inspection (TPI via SGS, BV, TÜV on request)

ASTM A105 Carbon Steel Nippolet Chemical Composition

Element	Composition (%)
Carbon (C)	0.35 max.
Manganese (Mn)	0.60–1.05
Phosphorus (P)	0.035 max.
Sulfur (S)	0.040 max.
Silicon (Si)	0.10–0.35
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.

Limits for composition based on standards ASTM A105 / ASME SA-105. The figures provided are maximum limits and should be understood accordingly. The combined amount for copper, nickel, chromium, molybdenum and vanadium shall have an upper limit, whereas chromium and molybdenum addition together is limited as well, apart from their limits mentioned here.

Mechanical Properties of Carbon Steel Nippolets

Property	Requirement
Tensile Strength	485 MPa (70 ksi) min.
Yield Strength	250 MPa (36 ksi) min.
Elongation	22% min.
Reduction of Area	30% min.
Hardness	187 HB max.

Dimensions Chart of Carbon Steel Nippolets

Size (Nominal)	Dimension A (mm)	Dimension A (in)	Dimension B (mm)	Dimension B (in)	Dimension L (mm)	Dimension L (in)	Dimension W (mm)	Dimension W (in)
1/4″ × 1/8″	13	0.51	6	0.24	31	1.22	15.1	0.59
3/8″ × 1/8″	14	0.55	7	0.28	34	1.34	18.6	0.73
3/8″ × 1/4″	14	0.55	7	0.28	34	1.34	18.6	0.73
1/2″ × 1/8″	16.5	0.65	8	0.31	36.5	1.44	23	0.91
1/2″ × 1/4″	16.5	0.65	8	0.31	36.5	1.44	23	0.91
1/2″ × 3/8″	16.5	0.65	8	0.31	36.5	1.44	23	0.91
3/4″ × 1/8″	16	0.63	8	0.31	40	1.57	29	1.14
3/4″ × 1/4″	16	0.63	8	0.31	40	1.57	29	1.14
3/4″ × 3/8″	17	0.67	8	0.31	41	1.61	28.5	1.12
3/4″ × 1/2″	17	0.67	8	0.31	41.5	1.63	28.5	1.12
1″ × 1/4″	20	0.79	9	0.35	41	1.61	35.4	1.39
1″ × 3/8″	20	0.79	9	0.35	42.5	1.67	35.4	1.39
1″ × 1/2″	20	0.79	9	0.35	45	1.77	35.4	1.39
1″ × 3/4″	20	0.79	9	0.35	45	1.77	35.4	1.39
1-1/4″ × 1/4″	21	0.83	10	0.39	42	1.65	44.5	1.75
1-1/4″ × 3/8″	21	0.83	10	0.39	47	1.85	44.5	1.75
1-1/4″ × 1/2″	21	0.83	10	0.39	49	1.93	44.5	1.75
1-1/4″ × 3/4″	21	0.83	10	0.39	49	1.93	44.5	1.75
1-1/4″ × 1″	22	0.87	10	0.39	52	2.05	44.5	1.75
1-1/2″ × 1/4″	20	0.79	10.5	0.41	42.5	1.65	51	2.01
1-1/2″ × 3/8″	21	0.83	10	0.39	47	1.85	50	1.97
1-1/2″ × 1/2″	21	0.83	10	0.39	49	1.93	50	1.97
1-1/2″ × 3/4″	21	0.83	10	0.39	49	1.93	50	1.97
1-1/2″ × 1″	21.5	0.85	11	0.39	52.5	2.07	50	1.97
1-1/2″ × 1-1/4″	22	0.87	11	0.43	55	2.17	51	2.01
2″ × 3/8″	23	0.91	11	0.43	52	2.05	61.5	2.42
2″ × 1/2″	23	0.91	11	0.43	52	2.05	61.5	2.42
2″ × 3/4″	23	0.91	11	0.43	41.5	1.63	61.5	2.42
2″ × 1″	23	0.91	11	0.43	53.5	2.11	61.5	2.42
2″ × 1-1/4″	23	0.91	11	0.43	56	2.20	61.5	2.42
2″ × 1-1/2″	23	0.91	11	0.43	55.5	2.19	61.5	2.42
2-1/2″ × 3/4″	27.5	1.08	13	0.51	64	2.52	78	3.07
2-1/2″ × 1″	27.5	1.08	13	0.51	63.5	2.50	78	3.07
2-1/2″ × 1-1/4″	27.5	1.08	13	0.51	63.5	2.50	78	3.07
2-1/2″ × 1-1/2″	27.5	1.08	13	0.51	63.5	2.50	78	3.07
2-1/2″ × 2″	27.5	1.08	13	0.51	65.5	2.58	78	3.07
3″ × 1-1/2″	28	1.11	15	0.59	68	2.68	92	3.62
3″ × 2″	28	1.11	15	0.59	68.5	2.70	93	3.66
3″ × 2-1/2″	28.5	1.12	15	0.59	71	2.80	92	3.62
4″ × 2″	30	1.18	15	0.59	75	2.95	117	4.61
4″ × 2-1/2″	30	1.18	15	0.59	75	2.95	117	4.61
4″ × 3″	30	1.18	15	0.59	75	2.95	117	4.61

Carbon Steel Nippolets Wall Thickness Chart

Nominal Size (NPS) (Header × Branch)	Large End OD D1 (mm)	Small End OD D2 (mm)	End to End Height A (mm)	Large End Wall Thickness T1 (mm) [Sch 40]	Large End Wall Thickness T1 (mm) [Sch 80]	Large End Wall Thickness T1 (mm) [Sch 160]	Large End Wall Thickness T1 (mm) [XXS]	Small End Wall Thickness T2 (mm) [Sch 40]	Small End Wall Thickness T2 (mm) [Sch 80]	Small End Wall Thickness T2 (mm) [Sch 160]
1/4″ × 1/8″	13.7	10.3	57	2.2	3.0	3.7	6.1	1.7	2.4	—
3/8″ × 1/8″	17.1	10.3	64	2.3	3.2	4.0	6.4	1.7	2.4	—
3/8″ × 1/4″	17.1	13.7	64	2.3	3.2	4.0	6.4	2.2	3.0	—
1/2″ × 1/8″	21.3	10.3	70	2.8	3.7	4.8	7.5	1.7	2.4	—
1/2″ × 1/4″	21.3	13.7	70	2.8	3.7	4.8	7.5	2.2	3.0	—
1/2″ × 3/8″	21.3	17.1	70	2.8	3.7	4.8	7.5	2.3	3.2	—
3/4″ × 1/8″	26.7	10.3	76	2.9	3.9	5.6	7.8	1.7	2.4	—
3/4″ × 1/4″	26.7	13.7	76	2.9	3.9	5.6	7.8	2.2	3.0	—
3/4″ × 3/8″	26.7	17.1	76	2.9	3.9	5.6	7.8	2.3	3.2	—
3/4″ × 1/2″	26.7	21.3	76	2.9	3.9	5.6	7.8	2.8	3.7	4.8
1″ × 1/8″	33.4	10.3	89	3.4	4.5	6.4	9.1	1.7	2.4	—
1″ × 1/4″	33.4	13.7	89	3.4	4.5	6.4	9.1	2.2	3.0	—
1″ × 3/8″	33.4	17.1	89	3.4	4.5	6.4	9.1	2.3	3.2	—
1″ × 1/2″	33.4	21.3	89	3.4	4.5	6.4	9.1	2.8	3.7	4.8
1″ × 3/4″	33.4	26.7	89	3.4	4.5	6.4	9.1	2.9	3.9	5.6
1-1/4″ × 1/8″	42.2	10.3	102	3.6	4.9	6.4	9.7	1.7	2.4	—
1-1/4″ × 1/4″	42.2	13.7	102	3.6	4.9	6.4	9.7	2.2	3.0	—
1-1/4″ × 3/8″	42.2	17.1	102	3.6	4.9	6.4	9.7	2.3	3.2	—
1-1/4″ × 1/2″	42.2	21.3	102	3.6	4.9	6.4	9.7	2.8	3.7	4.8
1-1/4″ × 3/4″	42.2	26.7	102	3.6	4.9	6.4	9.7	2.9	3.9	5.6
1-1/4″ × 1″	42.2	33.4	102	3.6	4.9	6.4	9.7	3.4	4.5	6.4
1-1/2″ × 1/8″	48.3	10.3	114	3.7	5.1	7.1	10.2	1.7	2.4	—
1-1/2″ × 1/4″	48.3	13.7	114	3.7	5.1	7.1	10.2	2.2	3.0	—
1-1/2″ × 3/8″	48.3	17.1	114	3.7	5.1	7.1	10.2	2.3	3.2	—
1-1/2″ × 1/2″	48.3	21.3	114	3.7	5.1	7.1	10.2	2.8	3.7	4.8
1-1/2″ × 3/4″	48.3	26.7	114	3.7	5.1	7.1	10.2	2.9	3.9	5.6
1-1/2″ × 1″	48.3	33.4	114	3.7	5.1	7.1	10.2	3.4	4.5	6.4
1-1/2″ × 1-1/4″	48.3	42.2	114	3.7	5.1	7.1	10.2	3.6	4.9	6.4
2″ × 1/8″	60.3	10.3	165	3.9	5.5	8.7	11.1	1.7	2.4	—
2″ × 1/4″	60.3	13.7	165	3.9	5.5	8.7	11.1	2.2	3.0	—
2″ × 3/8″	60.3	17.1	165	3.9	5.5	8.7	11.1	2.3	3.2	—
2″ × 1/2″	60.3	21.3	165	3.9	5.5	8.7	11.1	2.8	3.7	4.8

Applications and Industrial Uses

Oil and gas pipelines
Refineries
Petrochemical plants
Power generation facilities
Chemical processing
Pharmaceutical plants
Process piping systems

Frequently Asked Questions

What are Carbon Steel Nippolets?

Carbon Steel Nippolets are forged branch outlet fittings used to connect smaller branch pipes to main pipelines.

What are Carbon Steel Nippolets used for?

They are used for branch connections in oil and gas, refineries, petrochemical plants, power plants, and process piping systems.

What is the difference between a Nippolet and a Nipple?

A Nippolet is a branch outlet fitting with a forged base, while a nipple is a short pipe section, typically threaded at both ends.

What grades are used to manufacture Carbon Steel Nippolets?

Common grades include ASTM A105, ASTM A350 LF2, and ASTM A694, depending on the service requirements.

Are Carbon Steel Nippolets available in ASTM A105?

Yes. ASTM A105 is a commonly used forged carbon steel grade for Nippolets, particularly for pressure piping applications.

When should I use a Nippolet instead of a Sockolet plus a nipple?

Use a Nippolet when you want the branch outlet and nipple extension in one forged piece, reducing welds and leak paths. A Sockolet plus separate nipple is better when a non-standard standoff length is required.

What standoff length should I specify?

Standard Nippolets typically have 89–165 mm standoff lengths. Choose the length based on pipe insulation and instrument mounting requirements.

When should I opt for a nippolet rather than a sockolet and nipple?

The nippolet is a combination of the branched outlet and the nipple extension, which means that one fewer welded or threaded connection is needed in the assembly. In other words, an extra leak path and inspection point are avoided for instrumentation taps, pressure gauges, thermowells and vents. The alternative to the nippolet is the combination of a sockolet and a separate nipple in the situations when the standoff length is not a standard length and thus cannot be forged in.

What length of standoff is needed?

Nippolets are available in standard sizes ranging from 89 mm to 165 mm from the pipe surface to the outlet face. The length depends on the insulation thickness of the pipe and the needs for instrument installation, as it is usually pre-determined by the instrument standard stipulated in the project. Please forward the instrument standard to us for us to confirm if we have it in stock or if it would need to be made according to request.