How to specify a pressure reactor and request a comparable quotation

The starting point is what must happen inside the reactor: reaction, mixing, dissolution, polymerisation or another operation. Describe the objective of the batch or continuous operation, what goes in and what must come out, and which criterion will be used to accept the result. There is no need to disclose confidential formulations: a functional description is usually enough for initial guidance.

Three quantities frame any initial conversation: approximate working volume, expected operating pressure and temperature. These are preliminary input data, not design values: design conditions, scenarios and margins are determined by competent engineering during the project. Stating the phase or phases present (liquids, suspended solids, gas) also helps frame the configuration.

• Approximate working volume and expected variation between batches.
• Expected operating pressure and temperature, as preliminary data.
• Phases present and observable behaviour: foaming, settling, viscosity changes.
• Batch or continuous operation and approximate throughput.

Agitation is defined by what it must achieve: homogenising, keeping solids in suspension, promoting transfer or dispersing one phase into another. Describing the objective is more useful than requesting a specific agitator type, whose suitability the manufacturer assesses. On the thermal side, state whether the operation releases or requires heat, whether there are heating or cooling ramps and which utility fluids exist on site (steam, water, thermal oil, refrigeration).

If laboratory or pilot plant data exist — observed mixing times, scale-up behaviour, detected problems — it is worth mentioning them as a reference. They are not mandatory: part of the definition work consists precisely in identifying which data are missing and who will generate them.

Material compatibility is verified case by case. As input, it is enough to describe the nature of the fluid in generic terms (acidity, presence of chlorides, abrasion) and any previous experience with materials in similar services, without turning it into a closed specification. Also list the services the reactor will need: feeds, discharges, vents, sample points, minimum instrumentation and cleaning connections.

Finally, the installation context shapes the proposal: destination country and applicable legal framework, available space, clear height, lifting means and desired timeline. These data do not design the reactor, but they prevent proposals that are unfeasible for reasons unrelated to the process.

• Which category and conformity assessment module would apply under the pressure equipment directive, where applicable.
• Which documentation is included: drawings, material certificates, test reports, manual and instructions.
• Which tests and examinations are included and which are excluded from the scope.
• What additional information the manufacturer needs to finalise the proposal.
• Which responsibilities remain on the buyer's side: foundations, connections, utilities, installation and commissioning.

An enquiry structured around these points allows quotations to be compared on the same basis and reduces surprises during the project. You can prepare your summary with this site's form: it is generated locally and is not sent automatically.

• Asking for «a reactor of so many litres» without describing the operation: volume alone does not define the solution.
• Closing the material or agitator type before competent engineering assesses the service.
• Not distinguishing between operating conditions and design conditions, which are determined during the project.
• Comparing prices without harmonising scopes: documentation, testing, exclusions and responsibilities.
• Not stating the country of installation, which determines the legal framework applicable to putting into service.

None of these mistakes is serious if corrected in time: a good technical-commercial conversation starts precisely by putting them on the table. The more verifiable information the buyer provides in the first enquiry, the more comparable the response will be and the fewer iterations will be needed to reach a serious proposal that both sides can evaluate.