Pipe Schedule Dimensions Chart

Pipe Schedule Wall Thickness & Weight Chart

Each cell shows Wall Thickness (mm) / Weight (kg/m). A dash (-) indicates the schedule is not defined for that NPS. Weight is calculated using the formula: W = (OD − WT) × WT × 0.02466.

Weight Calculation Formula

How Kanpur contractors specify schedule

When you write a Kanpur RFQ, you should copy the schedule, NPS, material grade, design code and exact wall from the approved drawing or tender schedule. Do not infer Schedule 40 from a water or fire-system label, or Schedule 80 from the words "high pressure." Where a line falls under boiler jurisdiction, name the required IBR forms (Form III-A for steam pipes, Form III-B for boiler tubes, Form III-C for boiler mountings and fittings only) and leave the exact document set to the approved inspection plan.

Component drawings may instead call for precision tube. Water-well casing may name IS 4270 or another project-approved product standard. A close OD does not make those products interchangeable with schedule pipe. Name the required MTC type, heat or lot traceability, inspection scope, packing and delivery basis in the enquiry. Then treat the accepted quotation and purchase order as the commercial record. The borewell guide, Kanpur procurement page and dated market reference give separate RFQ context.

Schedule 40 versus 80: price bands in Kanpur

At the same NPS, the listed Schedule 80 wall carries more theoretical steel mass per metre than Schedule 40. Total commercial cost still depends on the written per-kilogram or per-length rate and its complete scope. The indicative seamless bands below are ex-warehouse Kanpur, reviewed 24 May 2026, and exclude GST at 18 percent as published on the seamless price list on that date. They are dated references, not firm quotes or current tax guidance.

For the two sizes shown, the Schedule 80 band endpoints are roughly 19 to 20 percent above the corresponding Schedule 40 endpoints as of 24 May 2026, while the bands themselves can overlap. That gap is per kilogram, not a universal premium, and only for these two sizes on that date. Total cost per length also changes because Schedule 80 carries more kilograms per metre. The full band table is on the seamless pipe price list. The Schedule 40 versus 80 comparison works through weight side by side.

RFQ checklist for schedule pipe

A schedule number on its own leaves the wall, the grade and the freight open. Send us these ten items with every schedule enquiry to Kanpur.

• NPS plus DN: state both, for example 2 inch (DN 50), so the OD is fixed.
• Schedule plus exact wall: write Sch 40 with 3.91 mm, since STD diverges above NPS 10.
• Standard and grade: ASTM A106 Grade B, A53, or API 5L with PSL level where relevant.
• Length: single random 5.8 or 6.0 m, double random 9 to 12 m, or cut-to-length.
• End finish: plain end, beveled for butt weld, or threaded with couplings on small sizes.
• Quantity in lengths and MT: both figures, so we can plan freight and truck fill.
• Test certificate: name the required MTC type and any IBR forms (Form III-A for steam pipes, Form III-B for boiler tubes, Form III-C for boiler mountings and fittings only), subject to the approved inspection plan.
• Inspection: name any agency or approval process, scope, hold points, location, fees and release evidence in the RFQ, and confirm the allocation in the written quotation.
• Coating: bare, epoxy, FBE or 3LPE for buried and cross-country service.
• Delivery basis: destination PIN with ex-warehouse Kanpur versus delivered terms.

Worked example: 2 inch Sch 40 against Sch 80

Take 2 inch NPS with OD 60.3 mm. Schedule 40 uses a 3.91 mm wall: (60.3 minus 3.91) times 3.91 times 0.02466 gives 5.44 kg per metre. One 6 m length weighs about 32.6 kg. Sixty lengths total about 1,957 kg, which is 1.96 MT.

Schedule 80 at the same OD uses a 5.54 mm wall, which computes to 7.48 kg per metre. The listed wall is therefore about 38 percent heavier per metre for this nominal size. Wall thickness changes one term in a pressure-design calculation. The comparison does not assign a design pressure or approval to either schedule. Run the applicable ASME B31.1 or B31.3 calculation with material allowable stress at design temperature, joint factors, dimensional tolerance, corrosion allowance and other code terms before you lock the schedule.

Common mistakes in schedule procurement

The classic error is assuming STD always equals Schedule 40. It does up to NPS 10, then the two diverge and an STD order can arrive thinner than the design assumed. The mirror error hits XS above NPS 8. A second mistake is mixing schedule language with IS 1239 class language on one order. A quotation that names B class is not automatically supplying Schedule 40, even where walls look close at one size. Convert both to OD and wall in mm first.

A third mistake is reading NPS as a measured bore. A 2 inch pipe has a 60.3 mm OD. Fit-up fails when fabricators cut to a 50 mm assumption. A fourth is specifying XXS by default for safety. Double extra strong walls cost far more per metre. Threading and welding procedures take extra work, and the supports carry the added dead load. Let the governing design code and project specification pick the schedule. Do not add XXS as a default safety margin on the purchase order.

Standards and compliance

ASME B36.10M governs the wall and diameter tables behind every schedule number on this page. It covers welded and seamless wrought steel pipe for high or low temperatures and pressures. The catalogue page is linked under References. The thin-wall Barlow relationship, P equals 2 times S times t divided by D, shows how wall and stress basis affect pressure, but it is not a design-pressure result on this page. Substituting a material's yield strength for the code allowable stress would overstate a usable design pressure. ASME B31.1 or B31.3 design also accounts for temperature, joint and quality factors, allowances and dimensional tolerance. Put the schedule, the standard and the grade in their own PO fields, and name the governing design code on its own line.

References

• ASME B36.10M: Welded and Seamless Wrought Steel Pipe, American Society of Mechanical Engineers. Catalogue page (fetched HTTP 200, 3 Sep 2026): asme.org: B36.10M welded and seamless wrought steel pipe.
• ASTM A106/A106M: Seamless Carbon Steel Pipe for High-Temperature Service, ASTM International. Cited by code for Grades A, B and C.
• ASME B31.1 / B31.3: Power Piping and Process Piping, American Society of Mechanical Engineers. Cited by code for design pressure calculation.

Frequently Asked Questions

Related Resources

• Steel Pipe Weight Calculator
• ERW Pipe Supplier in Kanpur
• Seamless Steel Pipes in Kanpur
• IS 1239 Standard: Full Reference
• ASTM A106 Standard: Full Reference
• Steel Pipes Supplier in Kanpur
• Kanpur Steel Market Buyer Guide