Email: sales@kelorvalves.com
Phone: +91 93135 43530
Address: 133/1 Ground, Mansuri Block, Opp. Dudheshwar Water Tank, Ahmedabad-380004, Gujarat, India
KELOR Valves — An incomplete or vague flange RFQ is the number one reason for delayed quotations, misquoted orders, and costly rework in industrial procurement. This guide provides a systematic, field-proven approach to writing flange RFQs that elicit fast, accurate, and comparable quotes from Indian flange suppliers — complete with a ready-to-use RFQ template and a filled sample for reference.
Guide at a Glance
12 Essential FieldsEvery RFQ must include
Template IncludedCopy, fill, and send
Sample RFQFilled example for reference
Quote Speed12-24 hrs with complete data
Table of Contents
- Why RFQ Quality Directly Affects Your Quote
- 12 Essential Data Points for a Flange RFQ
- 7 Common RFQ Mistakes That Delay Quotes
- Flange Type Reference for Your RFQ
- RFQ Template — Ready to Copy & Fill
- Sample Filled RFQ — SS304 Weld-Neck Flange
- How to Evaluate Supplier Quotes
- 8 Tips for Faster, More Accurate Quotes
- Frequently Asked Questions
1. Why RFQ Quality Directly Affects Your Quote
An RFQ (Request for Quotation) is the foundational document in industrial procurement — it communicates your exact requirements to the supplier and forms the basis for the commercial offer you receive. For industrial flanges, where specifications span multiple dimensions (type, size, material, pressure class, facing, standard, certification), even a single missing data point forces the supplier to either guess (risking an inaccurate quote) or send a clarification email (adding 1–3 business days to the response time). In a competitive bidding scenario, this delay can cause you to miss quotation deadlines, lose negotiating leverage, or receive non-comparable quotes from different suppliers because each made different assumptions about your missing specifications.
68%RFQs received are incomplete
2–5 daysDelay from missing data
12–24 hrsQuote time with complete RFQ
35%Of orders need rework from vague RFQs
The Real Cost of a Poor RFQ
Beyond delayed responses, an incomplete RFQ creates cascading problems throughout the procurement chain. The supplier assumes the cheapest specification to remain competitive — for example, quoting a slip-on flange when you needed a weld-neck, or Class 150 when your design requires Class 300. These mismatches are typically discovered during inspection or installation, forcing emergency re-orders at premium prices, schedule delays, and potential safety issues if the wrong flange is installed on a pressure system. Investing 15 minutes in a thorough RFQ eliminates weeks of downstream problems.
2. The 12 Essential Data Points Every Flange RFQ Must Include
The following twelve data points represent the minimum information required for any Indian flange supplier to provide an accurate, firm quotation without clarification. Each field directly affects the flange’s dimensions, material cost, manufacturing process, or delivery logistics. Omitting any one of these forces assumptions that may not align with your actual requirements.
| # | Data Point | Why It Matters | Example |
|---|---|---|---|
| 1 | Flange Type | Determines shape, forging process, and price. Weld-neck costs 30–40% more than slip-on for the same size/class. | Weld-Neck, Slip-On, Blind, Socket Weld, Threaded, Lap Joint, Long Weld-Neck, Spectacle Blind, Orifice |
| 2 | Size (NPS / DN) | Directly drives material weight, machining time, and price. Price scales non-linearly with size. | 2″ (DN50), 6″ (DN150), 24″ (DN600) |
| 3 | Pressure Class | Determines thickness, bolt circle, and number of bolt holes. Class 300 is ~50% heavier than Class 150. | Class 150, 300, 600, 900, 1500, 2500 |
| 4 | Material Grade | Largest cost variable. SS316 costs 40–50% more than SS304; CS is 60–70% cheaper than SS304. | A105/A105N, SS304 (CF8), SS316 (CF8M), A182 F5, A182 F91, A350 LF2 |
| 5 | Applicable Standard | Defines all dimensional tolerances, pressure-temperature ratings, and testing requirements. | ASME B16.5 (NPS 1/2″–24″), ASME B16.47 Series A/B (NPS 26″–60″), EN 1092-1, BS 4504 |
| 6 | Face Type | Affects sealing surface, gasket compatibility, and machining cost. RTJ requires precision groove machining. | Raised Face (RF), Flat Face (FF), Ring Type Joint (RTJ), Tongue & Groove |
| 7 | Quantity | Drives discount tier. 500 pcs qualifies for 15–25% off list; 10 pcs gets no discount. | Per line item, total project quantity |
| 8 | End-Use Application | Helps supplier verify material suitability and suggest alternatives if needed. Critical for safety. | Chemical process piping, offshore platform, water treatment, pharmaceutical, high-temperature steam |
| 9 | Certifications Required | NACE, PED, TPI, or special testing adds 5–15% to cost. Must be stated upfront to avoid re-quoting. | EN 10204 3.1 MTC, NACE MR0175, PED 2014/68/EU, TPI by SGS/Lloyd’s |
| 10 | Delivery Timeline | Expedited delivery (3–5 days) costs 10–20% premium over standard (15–25 days). Be realistic. | Standard 15–20 days, expedited 5–7 days, specific date required |
| 11 | Delivery Destination | Determines freight cost and logistics method. Remote locations or project sites cost more. | Ex-works Ahmedabad, FOB Mumbai Nhava Sheva, CIF Mundra, delivered to site |
| 12 | Quote Validity | Stainless steel prices are volatile. A 30-day validity may expire before your PO is approved. | 30 days, 60 days, 90 days, or “firm until [date]” |
3. Seven Common RFQ Mistakes That Delay Quotes
After reviewing thousands of flange RFQs over the years, the following seven mistakes are the most frequent causes of delayed, inaccurate, or non-comparable quotations. Each one is easily avoidable once you are aware of it, and addressing all seven will immediately improve your supplier response quality and speed.
1
Missing Pressure Class
Stating only the size (e.g., “6 inch SS304 flange”) without the pressure class is the most common RFQ error. The supplier cannot determine the flange thickness, bolt circle, or weight without this. Always specify: “6” Class 150 RF” or “6” Class 300 RF”.
2
Vague Material Specification
Writing “stainless steel” or “SS” instead of the specific grade (SS304, SS316, SS316L, duplex 2205) forces the supplier to assume SS304 — which may be wrong for your corrosive environment. Always use the full material designation.
3
No Application Context
Without knowing the service (water, acid, steam, offshore), the supplier cannot verify material suitability. Specifying “high-chloride water treatment plant” allows the supplier to flag that SS316 should be used instead of SS304, preventing a costly mistake.
4
Missing Quantity per Size
RFQs that say “various sizes, see drawing” without a tabulated quantity list force the supplier to count from drawings — error-prone and time-consuming. Always provide a clear table with quantities per item.
5
Conflicting Standards
Specifying ASME B16.5 dimensions with EN 1092-1 facing or mixing inch and metric sizes in the same RFQ creates confusion. Pick one primary standard and stick with it throughout the document.
6
Unclear Incoterms
Not specifying delivery terms (ex-works, FOB, CIF, delivered) means each supplier quotes different terms — making price comparison impossible. Specify the same incoterm for all suppliers you approach.
7
No Quote Validity Period
In a volatile stainless steel market, a quote without a stated validity period may expire before your internal PO approval process completes. Always request at least 60-day validity for project RFQs.
4. Flange Type Quick Reference for Your RFQ
Selecting the correct flange type is essential before submitting your RFQ. Each flange type has a specific purpose, cost profile, and installation requirement. Using the wrong type in your specification will result in receiving quotes for flanges that are either over-specified (wasting budget) or under-specified (creating safety risks). The table below provides a concise selection guide based on the most common industrial scenarios encountered in Indian process plants and piping projects.
| Flange Type | Best For | Relative Cost | Key Specification |
|---|---|---|---|
| Weld-Neck (WN) | High-pressure, high-temperature, cyclic service, critical piping | Baseline (+30% vs SO) | ASME B16.5, B16.47 |
| Slip-On (SO) | Low-to-moderate pressure, non-critical service, cost-sensitive projects | Lowest cost | ASME B16.5 |
| Blind (BL) | Line isolation, pressure testing, future connection points | Similar to WN | ASME B16.5, B16.48 |
| Socket Weld (SW) | Small bore (NPS 1/2″–2″), high-pressure small-diameter piping | 10–15% below WN | ASME B16.5 |
| Threaded / Screwed | Small bore, low-pressure utility lines, instrument connections | Lowest for small sizes | ASME B16.5 |
| Lap Joint (LJ) | Stainless or exotic material piping with stub-end; frequent dismantling | Stub-end + backing flange | ASME B16.5 |
| Long Weld-Neck (LWN) | Nozzle flanges, vessel connections, where a straight pipe section is needed | 20–30% above WN | ASME B16.5 |
| Orifice (ORF) | Flow measurement points with orifice plate installation | 40–60% above WN | ASME B16.36 |
5. RFQ Template — Ready to Copy, Fill & Send
The template below covers all twelve essential data points in a structured format that Indian flange suppliers can process immediately. Copy this template into your email or RFQ document, fill in the highlighted fields, attach any supplementary drawings or specifications, and send. A complete RFQ using this format typically receives a response within 12–24 hours from established suppliers.
Flange RFQ Template — Copy & Fill
SUBJECT: RFQ — Industrial Flanges — [Company Name] — [Project Name/Ref]
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1. BUYER INFORMATION
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Company: [Your Company Name]
Contact: [Your Name, Designation]
Email: [your.email@company.com]
Phone: [+91 XXXXX XXXXX]
GST No: [Your GST Number]
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2. PROJECT INFORMATION
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Project: [Project Name / Reference Number]
Location: [Project Site / Plant Location]
Application: [e.g., Chemical process piping, water treatment,
offshore platform, pharmaceutical plant]
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3. REQUIREMENT TABLE
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S.No | Flange Type | Size | Class | Material | Face | Std | Qty
-----|-------------|------|-------|----------|------|---------|-----
1 | Weld-Neck | 2" | 150 | SS304 | RF | B16.5 | 50
2 | Slip-On | 4" | 150 | SS304 | RF | B16.5 | 30
3 | Blind | 4" | 150 | SS304 | RF | B16.5 | 10
4 | Weld-Neck | 6" | 300 | SS316 | RF | B16.5 | 25
5 | [Add rows as needed]
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TOTAL PIECES: [Sum of Qty column]
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4. CERTIFICATIONS & TESTING
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Mill Test Certificate: [EN 10204 Type 3.1 / 3.2]
NACE MR0175: [Yes / No]
PED Compliance: [Yes / No — state directive if yes]
Third-Party Inspection: [Agency name or "Not required"]
Hydrostatic Test: [Per ASME B16.5 mandatory / waive request]
Radiography / PMI: [Yes / No — specify extent]
Painting / Coating: [As-supplied / painted / epoxy / galvanized]
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5. COMMERCIAL TERMS
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Incoterm: [Ex-Works / FOB Mumbai / CIF / DAP]
Delivery: [Required date or "Standard 15–20 days"]
Quote Validity: [30 / 60 / 90 days]
Payment Terms: [Your standard terms or "Open for discussion"]
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6. ADDITIONAL NOTES
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[Any special requirements: specific forging source,
packing instructions, marking requirements, partial
deliveries acceptable or not, etc.]
6. Sample Filled RFQ — SS304 & SS316 Weld-Neck Flanges
Below is a completed RFQ example demonstrating how the template should be filled for a realistic industrial project. This sample represents a chemical processing plant procurement package covering two material grades across multiple sizes and pressure classes. Notice how every field is populated — this eliminates all guesswork for the supplier and enables a precise, comparable quotation.
Sample Filled RFQ
SUBJECT: RFQ — Industrial Flanges — NPCPL — DM Plant Expansion Phase-II
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1. BUYER INFORMATION
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Company: NPCPL — Narmada Process Chemicals Pvt Ltd
Contact: Rajesh Kumar, Sr. Procurement Engineer
Email: rajesh.kumar@npcpl.in
Phone: +91 98765 43210
GST No: 24AABCN1234F1Z5
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2. PROJECT INFORMATION
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Project: DM Plant Expansion Phase-II — RFQ-2026-FL-014
Location: Dahej SEZ, Bharuch, Gujarat 392130
Application: Chemical process piping — caustic soda and
hydrochloric acid service, ambient to 180°C
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3. REQUIREMENT TABLE
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S.No | Type | Size | Class | Material | Face | Std | Qty
-----|-------------|------|-------|----------|------|--------|-----
1 | Weld-Neck | 2" | 150 | SS304 | RF | B16.5 | 80
2 | Weld-Neck | 3" | 150 | SS304 | RF | B16.5 | 40
3 | Weld-Neck | 4" | 150 | SS304 | RF | B16.5 | 60
4 | Weld-Neck | 6" | 150 | SS304 | RF | B16.5 | 30
5 | Weld-Neck | 8" | 150 | SS304 | RF | B16.5 | 15
6 | Slip-On | 2" | 150 | SS304 | RF | B16.5 | 100
7 | Blind | 2" | 150 | SS304 | RF | B16.5 | 30
8 | Blind | 4" | 150 | SS304 | RF | B16.5 | 20
9 | Blind | 6" | 150 | SS304 | RF | B16.5 | 10
10 | Weld-Neck | 2" | 300 | SS316 | RF | B16.5 | 50
11 | Weld-Neck | 4" | 300 | SS316 | RF | B16.5 | 25
12 | Weld-Neck | 6" | 300 | SS316 | RF | B16.5 | 10
13 | Blind | 2" | 300 | SS316 | RF | B16.5 | 15
14 | Blind | 4" | 300 | SS316 | RF | B16.5 | 10
-----|-------------|------|-------|----------|------|--------|-----
TOTAL: 495 pieces across 14 line items
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4. CERTIFICATIONS & TESTING
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Mill Test Certificate: EN 10204 Type 3.1 mandatory
NACE MR0175: Yes — for all SS316 items
PED Compliance: Not required (domestic project)
Third-Party Inspection: Lloyd's India — visual and
dimensional for 10% of each line item
Hydrostatic Test: Per ASME B16.5 (mandatory, not waived)
PMI Testing: 100% PMI on all SS items to verify
SS304 vs SS316 segregation
Painting / Coating: As-supplied machined finish,
no painting required
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5. COMMERCIAL TERMS
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Incoterm: FOB Mumbai Nhava Sheva
Delivery: 20 working days from PO date
Quote Validity: 60 days from quote date
Payment Terms: 30% advance, 70% against dispatch
documents and inspection report
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6. ADDITIONAL NOTES
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- All flanges must be from Indian source only.
- Each flange must be stamped with size, class, material,
heat number, and supplier logo.
- Packing: export-worthy with individual flange
identification tags.
- Partial deliveries acceptable in 2 lots if required
for production scheduling.
- Please confirm stock availability and tentative delivery
schedule in your quote response.
Why This Sample Works
This sample RFQ covers 495 pieces across 14 line items with complete specifications — every supplier receiving this document can quote immediately without a single clarification email. The total order value (₹8–15 lakh range at 2026 prices) qualifies for significant bulk discount negotiation. The 60-day quote validity accounts for typical EPC approval cycles. The Lloyd’s TPI requirement is clearly scoped (10% visual/dimensional) so the supplier can price it accurately rather than inflating the quote with worst-case TPI assumptions.
7. How to Evaluate Flange Supplier Quotes
Receiving multiple quotes is only valuable if you can compare them on an equal basis. The evaluation checklist below ensures you are comparing apples to apples rather than being misled by apparent price differences that stem from different assumptions, material grades, or commercial terms. Always create a comparison spreadsheet with the following columns when evaluating two or more flange quotes for the same requirement.
| Evaluation Criteria | What to Check | Common Pitfall |
|---|---|---|
| Material Compliance | Verify the exact ASTM/EN material grade quoted matches your RFQ (SS304 = ASTM A182 F304/A240, SS316 = A182 F316/A240) | Supplier quotes SS304 when you specified SS316 — appears cheaper but is non-compliant |
| Standard Conformance | Confirm ASME B16.5 / B16.47 / EN 1092-1 as specified — dimensions, tolerances, and pressure ratings must match | Supplier quotes to Indian IS standard instead of ASME — dimensions may differ |
| Certification Cost Included? | Verify MTC, NACE, TPI, and testing costs are included in the unit price, not quoted separately as add-ons | Low unit price but ₹50,000 added for NACE testing and TPI that others included |
| Delivery Terms | Confirm all quotes are on the same Incoterm (ex-works, FOB, CIF, DAP) — freight cost can swing total by 5–12% | Comparing ex-works price against DAP delivered price — the cheaper ex-works quote may cost more total |
| Quote Validity | Check validity period — 30-day validity in a volatile market may expire before your PO is approved | Selecting the cheapest quote with only 15-day validity while others offer 60 days |
| Delivery Timeline | Verify quoted delivery matches your project schedule — emergency expedited delivery costs 10–20% premium | Fastest delivery supplier is cheapest but cannot meet your required 10-day deadline |
| Payment Terms | Compare payment terms — 100% advance vs 30/70 vs LC at sight affects your working capital cost | Supplier offers 5% lower price but demands 100% advance payment |
8. Eight Tips for Getting Faster, More Accurate Flange Quotes
Beyond the template and data points, these practical tips are drawn from years of experience processing flange RFQs on both the buyer and supplier sides of the table. Implementing even half of these will noticeably improve your procurement efficiency.
1. Use a Table, Not Paragraphs
Tabulate your flange requirement with columns for type, size, class, material, face, standard, and quantity. Paragraph-style descriptions force the supplier to parse text into a table — error-prone and slow. A table is instantly processable.
2. Attach the P&ID or Line List
Even if your RFQ table is complete, attaching the relevant P&ID drawings or piping line list gives the supplier full context. They can cross-verify your specifications against the process conditions and flag any mismatches proactively.
3. Specify RTJ Ring Number for RTJ Faces
If you need Ring Type Joint facing, always specify the ring number (R11, R23, R45, etc.) or the groove dimensions per ASME B16.20. Different ring numbers require different groove machining, and the supplier cannot guess correctly.
4. State “Domestic” or “Import” Preference
Indian suppliers can source from domestic forges (faster, lower freight) or imported material (sometimes cheaper for exotic grades). Stating your preference avoids quotes that include unexpected import duty or extended delivery for material sourcing.
5. Group Sizes for Volume Leverage
Include all flange types, sizes, and materials in a single RFQ rather than sending separate enquiries per type. Total order value determines the discount tier — a combined RFQ of 500 pieces across 15 items gets better pricing than 15 separate RFQs of 30–40 pieces each.
6. Mention If Replacements Are Acceptable
State whether the supplier can offer equivalent grades (e.g., A105N instead of A105, or CF8M instead of F316 for forged flanges). This opens alternative sourcing options and may reduce cost and delivery time.
7. Request Weight in the Quote
Ask the supplier to include per-piece weight in the quote. This allows you to verify pricing consistency (₹/kg comparison), calculate freight costs, and compare weight across suppliers for the same specification.
8. Send Identical RFQs to All Suppliers
Send the exact same RFQ document — same specifications, same commercial terms, same format — to 2–3 suppliers simultaneously. This is the only way to ensure price comparison is meaningful. Modifying the RFQ per supplier defeats the purpose.
Pro Tip: The 24-Hour Follow-Up
If you have not received a response within 24 hours of sending a complete RFQ to an established Indian flange supplier, follow up with a phone call or WhatsApp message. Large suppliers receive dozens of RFQs daily, and yours may have been buried in the queue. A polite follow-up typically moves your enquiry to the top of the processing queue and demonstrates procurement urgency that often translates into better pricing. For project-critical RFQs with aggressive timelines, calling before sending the RFQ to confirm the supplier’s current lead time and capacity is even more effective.
Ready to Submit Your Flange RFQ?
Use the template above or simply email your flange requirement to KELOR — we respond to complete RFQs within 12 hours.
📧 Email: sales@kelorvalves.com 📞 WhatsApp InquiryFrequently Asked Questions
What information is required in a flange RFQ?
A complete flange RFQ must include: flange type (slip-on, weld-neck, blind, socket weld, threaded, lap joint, spectacle blind, or orifice flange), size (NPS and DN), pressure class (150, 300, 600, 900, 1500, or 2500), material grade (A105, SS304/CF8, SS316/CF8M, alloy steels like F5, F9, F91, or low-temperature grades like LF2), applicable standard (ASME B16.5 for NPS 1/2″–24″, B16.47 for 26″–60″, or EN 1092-1), facing type (RF, FF, or RTJ with ring number), quantity per item, end-use application description, required certifications (MTC, NACE, PED, TPI), delivery timeline, destination incoterm, and quote validity period. Missing any of these fields results in clarification emails that typically delay your quote by 1–3 business days.
How long does it take to get a flange quote from Indian suppliers?
For standard flanges with complete RFQ data as described in this guide, established Indian suppliers like KELOR Valves respond within 12–24 hours. Incomplete RFQs that require clarification emails typically take 2–5 days for a full round of back-and-forth before a quote is generated. For non-standard sizes (e.g., NPS 26″ and above), exotic materials (duplex 2205, super duplex 2507, inconel 625, hastelloy C276), or custom facings, quotes may take 2–4 working days even with perfectly complete data because the supplier must verify forge availability and lead times. Large project RFQs with 100+ line items may require 3–5 working days for detailed item-by-item pricing.
Should I send my RFQ to multiple flange suppliers?
Yes, and this is strongly recommended procurement best practice. Sending your RFQ to 2–3 verified suppliers ensures competitive pricing, validates availability, and provides negotiation leverage. Always send the identical RFQ to all suppliers simultaneously so the quotes are directly comparable on a per-item basis. Include your target delivery date and specify whether the quoted price should be firm for 30, 60, or 90 days. Be transparent about the approximate total order value — this helps suppliers prioritise your enquiry and apply the appropriate bulk discount tier from the outset rather than quoting list price and negotiating discounts later.
What is the difference between Class 150 and Class 300 flanges in an RFQ?
The ASME pressure class determines the flange’s pressure-temperature rating and all physical dimensions. A Class 300 flange of the same size is approximately 50% heavier, has a larger bolt circle diameter, more bolt holes, and is roughly 15–25% more expensive than the equivalent Class 150 flange. The class also affects the facing dimensions — RF height for Class 300 is larger than Class 150. Specifying the wrong class results in receiving flanges that physically do not match your existing piping system or do not meet the design pressure requirements. Always verify the correct pressure class from your piping line list, P&ID, or piping specification document before submitting the RFQ.
Can I use a single RFQ for multiple flange types and sizes?
Absolutely, and this is the recommended approach for project procurement. A well-structured tabular RFQ can include 50, 100, or even 200+ line items covering different flange types (weld-neck, slip-on, blind, socket weld, spectacle blind), sizes (1/2″ through 24″+), materials (CS, SS304, SS316, alloy steel), and pressure classes (150, 300, 600) in a single document. Consolidating your entire flange requirement into one RFQ is strategically advantageous because it shows the supplier your total order value, which often qualifies for higher bulk discount tiers than separate enquiries for each individual flange type or size.
What certifications should I request in a flange RFQ?
For standard industrial service, EN 10204 Type 3.1 mill test certificates with full chemical composition and mechanical properties (tensile strength, yield strength, elongation, impact values) are the baseline requirement. For oil and gas service handling sour (H2S-containing) fluids, add NACE MR0175 / ISO 15156 compliance and optionally HIC (Hydrogen Induced Cracking) and SSC (Sulphide Stress Cracking) testing per NACE TM0284 and TM0177. For European projects or equipment destined for EU installation, request PED 2014/68/EU compliance with CE marking. For critical service or client-mandated projects, specify third-party inspection (TPI) by a recognized agency such as TUV, Lloyd’s Register, SGS, Bureau Veritas, or DNV with defined inspection scope (visual, dimensional, NDT extent).
How do I specify surface finish for flanges in my RFQ?
For raised face (RF) flanges, specify the serrated finish type and roughness value: concentric or spiral serrated finish with Ra 3.2–6.3 micrometres (125–250 micro-inches) is the standard ASME B16.5 stock finish. For sensitive gasket materials (PTFE, graphite), specify a smoother finish of Ra 3.2 micrometres (125 micro-inches) or better. For RTJ flanges, specify the groove finish as Ra 1.6 micrometres (63 micro-inches) per ASME B16.20. For sanitary, pharmaceutical, or food-grade applications, specify electropolished or mechanically polished finish with Ra 0.8 micrometres or better per ASME BPE. Always reference the applicable measurement standard (ASME B46.1 for surface texture) to ensure the supplier and your inspection team are using the same methodology.