Short answer: for continuous line pipe in water, oil, gas and chemical service, hot-rolled (vacuum hot-rolled) bimetal clad pipe is the better buy — it bonds a stainless steel layer to a carbon-steel core with a ≥250 MPa metallurgical shear strength, verified by 100% ultrasonic inspection across the full length, in diameters from Φ20 to 3500 mm. Explosion bonding still wins for very thick flat segments and special alloys. This guide explains where each process wins so you can specify correctly.
Side-by-Side Comparison
| Criterion | Hot-Rolled Clad Pipe | Explosion-Bonded Clad |
|---|---|---|
| Bonding mechanism | Continuous metallurgical bond formed under heat and pressure across the full length | Impact bonding of plate segments; bond pattern varies by location |
| Bond strength | ≥250 MPa shear strength, verified by 100% ultrasonic inspection | High local strength; full-length verification required piece by piece |
| Diameter range | Φ20–3500 mm from one mill | Limited by plate size and forming |
| Wall thickness control | Uniform along the pipe; no liner to detach | Wider local variation after forming |
| Best suited for | Long transmission and distribution lines, spools, repeated batches | Thick flat or short segments, transition joints, special alloy pairs |
| Cost position | 30–50% material cost saving versus solid stainless, sustained at volume | Competitive on thick one-offs; less predictable on batches |
Where Hot-Rolled Clad Pipe Wins
Hot-rolled bonding forms the metallurgical bond while the composite wall is being rolled, so every square millimetre of the interface is created under the same process conditions. The practical consequences: a 50-year design life in corrosive service, no liner to detach and no coating to maintain, and mill test reports where the same numbers appear on every batch. For buyers consolidating 30–50% cost savings against solid stainless, the process consistency is what makes the saving safe to take.
Where Explosion Bonding Still Makes Sense
Explosion bonding produces large clad plates with strong local bonds and remains the right choice for very thick flat products, transition joints between dissimilar metals, and alloys that cannot be co-rolled. If your requirement is a thick flat head-and-plate assembly rather than pipe, explosion-clad plate is the correct specification — clad plates and coils from 0.17 to 400 mm are available on the same quality system.
What to Demand from Either Supplier
- Ultrasonic inspection records with stated coverage (insist on 100% for line pipe).
- Shear strength values per heat, not just per order.
- Mill test reports traceable to the bonded batch.
- Written execution standard — for hot-rolled clad pipe in China, GB/T 31940.
Is hot-rolled clad pipe suitable for high-temperature service?
Yes within the temperature envelope of the base and cladding steels specified — the bond is metallurgical and does not degrade with heat the way mechanical liners or coatings can. State your design temperature and medium when requesting the quotation so the material pairing is selected for it.
Can I order both pipe and flat clad products under one purchase order?
Yes — hot-rolled clad pipe, clad plates and coils are coordinated under one quality system and one purchase order, which is how engineering buyers keep container fill rates up and interface risk down.