Long Weld Neck Flange technical overview.
Long Weld Neck Flange from JINYI is presented in the NPS 2 · Class 150 · 228.6 mm configuration. Use the dimension schedule, connection details and inspection requirements below when comparing this product with your pipework or equipment drawing.
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What is a long weld neck flange?
A long weld neck flange combines a drilled flange with an extended neck for a specified nozzle or connection arrangement. Its additional projection can form part of a vessel or equipment connection detail.

Key dimensions and installation fit
Match the flange outside diameter, bolt circle, hole pattern and facing to the mating component. The nominal pipe designation identifies the connection family; it is not the flange outside diameter. For a replacement, measure the mating face and inspect the existing drilling before comparing the dimensional schedule. The slip on flange provides another pipe-attachment arrangement to compare when defining the connection; confirm which form the nozzle drawing requires.
How to specify the long weld neck flange
The flange, gasket, studs and nuts work as one bolted joint. Choose the material grade and gasket for the fluid and operating temperature, then select the flange designation required by the piping specification. A PN or Class label is a designation within a standard; it is not a universal working pressure independent of temperature and material.
Technical data for the long weld neck flange
| Nominal size | 2 in / DN50 |
|---|---|
| Pressure designation | Class 150 |
| Bore diameter | 50.8 mm |
| Outside diameter | 152.4 mm |
| Flange thickness | 19.1 mm |
| Barrel diameter | 82.6 mm |
| Overall length | 228.6 mm |
| Bolt circle diameter | 120.7 mm |
Sizes and dimensional requirements
The dimensional schedule identifies the illustrated configuration. Compare each value with the mating pipe, equipment or support drawing. A nominal designation does not replace the actual connection diameter, installation envelope or mounting detail. The choices above let you include a different configuration with your quotation request.
Dimensions and tolerance schedule
| Bolt circle diameter | ±1.52 mm |
|---|---|
| Adjacent bolt centres | ±0.76 mm |
Inspection, standards and documentation
Check outside diameter, thickness, bolt-circle position and adjacent-hole spacing with the drawing revision used for the order. Record the condition of the sealing face and protect it during packing. Bore, hub and barrel dimensions also matter on necked flanges because they determine how the flange attaches to the pipe or vessel.
State the required product standard and edition, material records and inspection acceptance criteria before ordering. Where pressure, temperature, movement or load are relevant, provide the operating and test conditions together. Document requirements should identify the actual component and drawing revision; a general certificate does not replace a dimensional or material record for the ordered item. For production steps and inspection considerations, see flanges and fittings manufacturing.
Where the long weld neck flange is used
- Process pipework. Select the flange connection for the piping specification, mating equipment and intended operating conditions.
- Equipment connections. Compare the nozzle geometry, bolt drilling, facing and gasket arrangement before finalising the interface.
- Maintenance and isolation. Plan access, joint opening and inspection around the actual closure or flange arrangement.
How to order a long weld neck flange
Select the required options and send the quantity, destination, material and controlled drawing to JINYI. Include changed dimensions, mating details, finish, marking and packing requirements. The quotation defines the final configuration, inspection scope and delivery terms so the component can be checked against the intended installation.
Quantity prices and order preparation
| 10–499 pcs | US$12.17 per piece |
|---|---|
| 500–999 pcs | US$5.21 per piece |
| 1,000 pcs and above | US$4.90 per piece |
Freight and taxes are quoted separately. A different material, size or drawing can change the price and delivery requirements. Confirm the agreed specification before manufacture, and keep the drawing revision, selected options and ordered quantity together in the enquiry.
Other JINYI products worth comparing
Compare blind flange, weld neck flange, or review the industrial pipe flanges catalog for other connection and configuration choices.
Request a custom long weld neck flange quotation from JINYI with the drawing and quantity required for your project.
Long Weld Neck Flange selection and quotation checklist
The extended barrel changes the nozzle envelope and attachment detail. Check the full projection from the flange face, rather than treating this component as a standard short weld neck flange. Use the photographed product form to identify the arrangement, then use the controlled drawing to define what will be supplied. Similar-looking components can have different end details, load paths or maintenance requirements.
Long Weld Neck Flange dimensions and tolerances
The first comparison for this long weld neck flange is barrel length and nozzle bore. Mark the dimensions that control mating, alignment and installation space on the enquiry drawing. Give units for every value and identify the datum from which it is measured. If a dimension is critical, specify its individual tolerance and measurement method rather than relying on a general tolerance note.
The current schedule identifies nominal size: 2 in / DN50; pressure designation: Class 150; bore diameter: 50.8 mm. Read these entries together with the configuration and tolerance tables above. Reference or example values describe the displayed arrangement; the approved JINYI quotation and drawing define the ordered component. A different interface, material or service condition needs a fresh comparison.
Prepare the material and interface information
For a long weld neck flange enquiry, identify the required material designation and supplied condition. Describe the mating components, attachment method and environment. Include the operating temperature and any relevant pressure, movement or structural load. These inputs should describe the actual installation, including changes between normal operation, start-up and maintenance where applicable.
Specify coatings, surface finish and marking separately from the base material. If traceability is needed, identify the record required and how it must correspond to the delivered component. Agree whether inspection covers dimensions, material documentation, welds or functional testing; these are different checks with different acceptance criteria.
Custom long weld neck flange quotation
Attach the latest drawing revision, required quantity and delivery destination when contacting JINYI. Highlight departures from the illustrated arrangement, including changed dimensions, connections, finish and packing. For repeat orders, reference the approved configuration and list changes explicitly so an earlier drawing is not assumed to remain current.
The three price tiers above organise the displayed quantity bands. Compare quotes using the same drawing, material, inspection scope and unit of supply. A piece, a segment and a complete assembly are different units where applicable. Confirm freight, taxes, documentation and delivery terms with the final quotation instead of inferring them from the displayed unit price.
Compare related component arrangements
Evaluate this nozzle flange by its actual barrel length and nozzle bore and the required neck flange arrangement. The photographs below show separate JINYI products for comparison. They are linked to their own technical pages and are not additional gallery views of this long weld neck flange.
| Photo | Related product | Selection detail |
|---|---|---|
![]() | Weld Neck Flange | Hub geometry and pipe bore. Compare this separate product when the drawing requires its particular arrangement. |
![]() | Slip On Flange | Bore clearance and hub height. Compare this separate product when the drawing requires its particular arrangement. |
![]() | Blind Flange | Bolt pattern and sealing face. Compare this separate product when the drawing requires its particular arrangement. |
Questions to resolve before ordering
Which dimensions need checking first?
Start with barrel length and nozzle bore and the mating or mounting detail. Check nominal designations against measured dimensions, then review the installation envelope. Photographs help identify the form; the drawing provides the dimensional basis for acceptance.
What should the quotation include?
A long weld neck flange quotation should identify the configuration, drawing revision, material, quantity, price basis and agreed inspection records. Keep these details together with the approved order so receiving inspection can compare the delivered product with the specified component.
Independent terminology reference
ASME flange standard scope provides an independent reference for component terminology. Use the specified standard and edition where required by the project. This link does not establish JINYI certification, product approval or interchangeability with another manufacturer.
- 2 in / DN50
- Nominal size
- Class 150
- Pressure designation
- ±1.52 mm
- Tolerance
- 3
- Quantity tiers
- Flange interface — Bolt circle, drilling, facing and nominal size are separate dimensions.
- Pressure selection — A pressure class is not a stand-alone pressure limit in psi or bar.
- Joint assembly — Bolting and gasket selection form part of the complete flange joint.
At a glance
- Product
- Long Weld Neck Flange
- Configuration
- NPS 2 · Class 150 · 228.6 mm
- Nominal size
- 2 in / DN50
- Pressure designation
- Class 150
- Bore diameter
- 50.8 mm
Dimensions and technical specification
| Parameter | Specification |
|---|---|
| Nominal size | 2 in / DN50 |
| Pressure designation | Class 150 |
| Bore diameter | 50.8 mm |
| Outside diameter | 152.4 mm |
| Flange thickness | 19.1 mm |
| Barrel diameter | 82.6 mm |
| Overall length | 228.6 mm |
| Bolt circle diameter | 120.7 mm |
| Bolt holes | 4 × Ø19.1 mm |
| Approximate weight | 6.81 kg |



















