Hydraulic-cylinder tube procurement starts with the approved drawing, not a regional or application default. Copy the exact standard, material designation, delivery condition, bore, wall, finish, tolerances, end condition and inspection plan. Legacy DIN and current EN vocabulary must be reconciled explicitly, not treated as an automatic equivalence.
For a Kanpur enquiry, ask the current written quotation to identify material location, availability, offered tolerances and documents, freight, risk transfer, legally applicable taxes and dates. No stock range or corridor timing is promised here.
The Indian hydraulic cylinder fabrication landscape
These four locations are useful destination labels, not evidence of demand or technical preference. The approved drawing controls finish, tolerance, delivery condition and inspection.
Coimbatore
Use Coimbatore only as a destination label. Copy the exact material designation, delivery condition, dimensions, bore finish, tolerance and inspection plan from the customer-approved drawing.
Pune / Pimpri-Chinchwad
For Pune enquiries, state the authorised destination and exact drawing requirements; this page does not claim named customers or a regional tolerance practice.
Faridabad / NCR
For Faridabad enquiries, copy the approved material, bore, wall, finish and delivery condition. Do not infer an SRB range or stock position from the region.
Pithampur (Indore)
For Pithampur enquiries, use the drawing and machining or welding plan to determine the delivery condition; no regional preference or availability is asserted.
The DIN 2391 St52 / EN 10305-1 E355 spec
A legacy DIN drawing and EN 10305-1 use different standards and designation systems. Preserve the drawing's exact callout and obtain designer and manufacturer clarification for any proposed translation, including material properties, delivery condition, tolerances and tests.
Surface finish — SRB vs honed
Skived-and-roller-burnished (SRB) is one finish route. The skiving cutter removes the cold-drawing tool marks and small ID irregularities; the roller burnishing densifies the bore surface. The drawing and ITP must state the required Ra, geometry, measurement and acceptance criteria.
Honed (H8) finish adds a separate machining operation that can produce a different geometry and texture. Select it only where the approved cylinder and seal design name it. Obtain the actual roughness, tolerance, price and lead-time effect from the drawing and current quotation.
Bore-size RFQ checklist
These example bores help organise an enquiry; they are not a stock statement, wall recommendation or delivery promise.
| Bore | Wall | Typical use |
|---|---|---|
| 50 mm | 5.0 mm | High-volume agriculture and material-handling cylinders |
| 63 mm | 5.0 mm | General industrial press and small mobile-equipment duty |
| 80 mm | 6.0 mm | Mid-range mobile equipment, agriculture, light construction |
| 100 mm | 7.5 mm | Standard construction-equipment cylinders |
| 125 mm | 8.0 mm | Heavy construction, mining-equipment cylinders |
| 160 mm | 10.0 mm | Heavy-duty press, large mobile-equipment cylinders |
| 200 mm | 12.5 mm | Heavy-press, mining-equipment, large hydraulic systems |
Heat-treatment condition — NBK, BKS, BKW
NBK
Normalised (DIN 2391 condition NBK). Heat-treated to a uniform fine-grained structure after cold drawing. Used where stress relief is needed for machining stability or for downstream welding work.
BKS
Cold-drawn and stress-relieved. Use only where the exact material standard, delivery condition and approved fabrication plan call for it.
BKW
Cold-drawn, hard. Highest mechanical properties from the cold drawing itself, no post-draw heat treatment. Specified where mechanical strength is paramount and downstream stress is not a concern.
Buying hydraulic cylinder tube in Kanpur
Use Kanpur as a proposed collection or coordination point only when the current offer confirms it. Send the approved drawing, material, finish, tolerance, length and inspection requirements. Historical comparison bands sit on our precision-tube price list, dated 24 May 2026; they are not current rates, stock or a tax rule.
Ask the current quotation to state availability, manufacturing route, milestones, inspection coordination, documents, freight, risk transfer, legally applicable taxes and dates. No agency, nationwide coverage or lead time is promised here. Start from the precision and hydraulic tubes catalogue and the DIN 2391 St52 spec page; the Kanpur steel market guide, steel pipes Kanpur page and Lucknow corridor page cover local buying practice and freight context.
Who should specify cold-drawn cylinder tube, and who should not
Cold-drawn SRB or honed tube may suit a cylinder design where its exact material, bore geometry, finish and delivery condition are approved. Application category alone does not prove seal performance or remove the need for machining and inspection.
Do not substitute structural or conveyance pipe for a drawing- specified cylinder tube. Delivery condition must be checked against machining, welding and heat-treatment plans. Compare finish costs only through a current quotation.
SRB finish versus honed bore: selection table
The table is a side-by-side RFQ aid, not a stock position or universal finish-selection rule. Verify every value against the approved drawing and current offer.
| Finish | Bore roughness (Ra, µm) | Price position | Choose it when |
|---|---|---|---|
| SRB | 0.2-0.4 | Base price | General industrial cylinders, press duty, agriculture and material handling |
| Honed (H8) | ≤ 0.2 | 30-50% above SRB | High-pressure systems, high cycle counts, cylinders where seal replacement is expensive |
Worked example: tube weight for a 100 mm bore cylinder
Theoretical weight for carbon steel tube uses W = (OD minus wall) times wall times 0.02466, with OD and wall in millimetres. Take a 100 mm bore with a 7.5 mm wall from the example table above. The resulting OD is 115.0 mm. Then W = (115.0 minus 7.5) times 7.5 times 0.02466, which gives 19.88 kg per metre. A 6 m length weighs 119.3 kg, so a 40-length order totals about 4.77 MT. Use that theoretical tonnage as an RFQ check; the accepted mass basis, vehicle and freight are order-specific. The same formula sits worked for IS 1239 sizes on our pipe weight chart.
RFQ checklist for a cylinder tube enquiry
Include these nine items for a current technical and commercial response without assuming stock or timing.
Include the cylinder assembly drawing and revision, not only a bore list. The useful review set identifies the piston and seal system, stroke, load direction, maximum and minimum design conditions, fluid, contamination control, corrosion exposure, weld and machining sequence, heat-treatment restrictions, straightness and runout datums, roughness measurement method, sampling and final acceptance owner. Those inputs let the designer confirm material, wall, delivery condition and finish without an application shortcut. Require every offered deviation to be listed explicitly. For cut lengths, add facing, clamping and machining allowances from the fabricator's process sheet. For witnessed inspection, identify the measuring equipment, calibration evidence, sample selection, report signatories and release status. Receipt teams can then compare the physical identity, dimensions and records against one controlled baseline instead of reconstructing intent from a sales description. Preserve that baseline for machining setup, inspection disposition and any later engineering change.
- Bore ID and wall (or OD and wall). Bore in mm with wall in mm, e.g. 100 mm bore x 7.5 mm wall.
- Finish. SRB or honed H8, with the Ra callout where the drawing states one.
- Condition. NBK, BKS or BKW to match the machining and welding plan.
- Length. State the required or offered length, or an approved cutting list and allowance.
- Quantity. Both lengths and approximate MT so freight can be quoted in one pass.
- Test records. State the inspection-document type, results, identity and traceability required by the drawing and PO.
- Inspection. Whether the OEM ITP needs witnessed inspection, and the witnessing agency.
- Consignee details. Provide authorised particulars required by current invoice and transport law and the contract.
- Delivery basis. Ask the offer to state material location, collection or destination basis, freight, risk transfer, taxes and dates.
Common procurement mistakes and inspection points
Ordering by OD alone without stating the bore leaves the wall undefined. An unapproved commercial tube can miss the specified bore-finish control. Reconcile the delivery condition with the approved welding and machining procedure.
At receipt, reconcile product identity and traceability with the required inspection document. Measure ID, OD, ovality and finish using the method, sampling and limits in the approved drawing and ITP; do not use a generic percentage.
Key points
- Do not treat DIN 2391 St52 and EN 10305-1 E355 as automatic equivalents; resolve mixed drawing language.
- Use the approved bore finish, roughness, geometry and measurement method.
- NBK, BKS and BKW set the heat-treatment condition. Confirm it before machining or welding.
- Confirm material location, availability, manufacturing route and lead time in the current quotation.
- Define test, traceability, finish, invoice and transport records from the PO and current law.
What the fabricator's QA cell will ask for
- Heat-treatment certificate. Confirms the NBK / BKS / BKW condition matches the PO spec.
- ID and OD ovality measurement. Per-pipe dimensional check showing ovality within the agreed tolerance limit.
- Burnishing finish certificate. Mill profilometer trace showing the Ra value and the trace plot for SRB or honed tubes.
- Material inspection document. Chemical, mechanical and traceability evidence at the level required by the exact standard, drawing and PO.
- Witnessed inspection release. Where the OEM ITP calls for witnessed inspection at the mill or yard, the release note from the witnessing party.
- Invoice and transport records. Prepare the particulars required by current law and the contract for the authorised consignee.
Related references for cylinder fabricators
- Precision & hydraulic tubes — catalogue
- DIN 2391 St52 — full spec page
- Precision tube manufacturing process
- CDW tubes (cold drawn welded)
- Indicative precision-tube price list
- Precision tubes — hydraulic applications
- Quality & documentation hub
- Mill test certificate sample walkthrough
- Buying guide: best pipes for hydraulic cylinder tubing
- All industries we serve
- Steel pipe & tube glossary
- Steel pipes — Kanpur wholesale page
- Seamless pipes — Kanpur page
- Steel pipes — Lucknow page
- Kanpur steel market — buyer's guide
- Pipe weight chart (worked formula)