Long weld neck flanges
BLD Forge Direct
Long Weld Neck Flange RFQ Support from China
I help overseas buyers review long weld neck flange RFQs based on standard, drawing, pressure class, material grade, overall length, neck OD, bore, facing, inspection requirements and destination country before quotation.
Direct RFQ Contact
Send drawings, standards, material grades, quantity and inspection requirements directly for project sales review.
Product Scope
Use this section to confirm whether the RFQ belongs on this product page before sending drawings or line-item details.
High hub flange designs
ASME LWN flanges by drawing
Class 150 to 2500 pressure projects
Custom overall length, neck OD and bore review
Forged blanks with machining allowance
Common Standards
Standards are checked against the drawing, project specification and requested inspection route.
- ASME B16.5
- Project drawings for custom long weld neck or high hub flanges
- ASME B16.47 where larger diameter project drawings require review
- EN / DIN or GOST references when the buyer drawing uses those systems
- ASTM material standards for carbon, low-temperature, stainless and duplex grades
Material Grades
Material review confirms grade, service condition, heat treatment and certificate expectations before quotation.
ASTM A105
ASTM A350 LF2
Stainless steel grades such as 304, 316, 321 or 347
Duplex and super duplex grades when specified
Project-specified alloy grades subject to drawing review
Size, Pressure, Class and Drawing Review Points
These items help prevent missing technical details during the first quotation review.
Overall length
Neck outside diameter
Bore and transition details
NPS / DN and pressure class / PN
Facing and bolt pattern
Material grade and heat treatment
Inspection requirement and destination country
Manufacturing Route
The practical route is reviewed before price and lead time are confirmed.
- Material review
- Forging route confirmation
- Heat treatment
- Rough machining
- Final machining
- Inspection and document review
- Marking, packing and export document preparation
Inspection and Documents
Inspection requirements should be included with the RFQ so document cost and timing are clear early.
MTC EN 10204 3.1
Heat treatment record
Dimensional report
PMI when alloy verification is required
UT, MT or PT when specified
Tensile, impact or hardness test records when required
Third-party inspection support by project request
RFQ Checklist
Include these details when sending the first message.
Standard or drawing
NPS / DN
Pressure class / PN
Overall length
Neck outside diameter
Bore
Facing
Bolt pattern
Material grade
Quantity
Heat treatment
Inspection requirement
Destination country
Third-party inspection need
Common Buyer Mistakes
These points often cause repeated clarification or delayed quotation.
- Sending a product name without standard, drawing or pressure rating
- Leaving bore, facing or bolt pattern unclear
- Mixing DN, NPS, PN and class references without a drawing
- Omitting inspection documents until after price discussion
- Forgetting destination country, packing or third-party inspection requirements
FAQ
Short answers for common RFQ questions.
Can you review custom long weld neck flanges by drawing?
Yes. Send the latest drawing revision with overall length, neck outside diameter, bore, facing, material grade, quantity and inspection requirements for review before quotation.
What information is needed before quotation?
The first RFQ should include standard or drawing, NPS or DN, pressure class or PN, overall length, neck outside diameter, bore, facing, bolt pattern, material, quantity, inspection and destination country.
Which materials are common for LWN flanges?
Common long weld neck flange materials include ASTM A105, A350 LF2, stainless steel grades and duplex grades, with final feasibility confirmed by drawing and project requirements.
What should buyers provide for Class 1500 or Class 2500 LWN flanges?
For high-pressure LWN flanges, provide the drawing, pressure class, bore, wall transition, facing, material, heat treatment, NDT requirements and any third-party inspection requirement.
Can inspection documents be arranged?
Inspection documents such as MTC 3.1, heat treatment records, dimensional reports, PMI, UT, MT, PT and third-party inspection support can be reviewed and arranged according to the project requirement.
Send your RFQ or drawing directly to BLD Forge Direct.
Email [email protected] with standard, drawing, material, quantity and inspection requirements.