How to Write a Technical RFQ for a Custom Process Ceramic Component

A request saying:

“Can you make this ceramic part?”

is not enough for reliable quotation.

Custom industrial ceramic cost and feasibility depend on more than:

• shape;
• quantity.

The supplier needs to understand:

• material;
• geometry;
• tolerance;
• temperature;
• chemical environment;
• mechanical function.

A good RFQ allows the manufacturer to decide not only whether the part can be produced, but whether the proposed ceramic is appropriate for the service.

Start With a Drawing

Provide a dimensional drawing whenever possible.

Useful formats include:

• PDF;
• STEP;
• other agreed CAD formats.

The drawing should identify:

• dimensions;
• tolerances;
• critical surfaces.

Photographs are useful supporting information but should not replace a controlled drawing for a precision custom part.

State the Application

Tell the supplier what the component does.

For example:

• chemical-process liner;
• high-temperature sleeve;
• catalyst support component;
• insulating collar;
• corrosion-resistant nozzle.

Application helps the supplier understand which properties matter most.

Identify the Material Requirement

Do not write only:

“ceramic.”

If a material is already specified, state:

• alumina grade;
• cordierite;
• mullite;
• SiC;
• another ceramic.

If material is not fixed, describe the service and allow the supplier to evaluate options.

Give Operating Temperature

State:

• normal temperature;
• maximum temperature;
• thermal cycling.

A part operating continuously at 800°C is different from a part repeatedly moving between 20°C and 800°C.

Give Process Chemistry

For chemically exposed parts, provide:

• chemical names;
• concentration;
• impurities;
• gas or liquid phase.

General phrases such as “corrosive service” are not enough for material selection.

Define Mechanical Load

Explain whether the ceramic is:

• carrying compression;
• clamped;
• cantilevered;
• exposed to impact;
• only acting as a liner.

The same shape can require very different design depending on the load mode.

Identify Critical Dimensions

Do not apply an unnecessarily tight tolerance to the whole drawing.

Mark only dimensions that control:

• fit;
• sealing;
• flow;
• assembly.

This reduces machining and rejection cost.

State Surface-Finish Requirements Only Where Necessary

If a face must seal against a gasket, specify the functional requirement.

If the exterior is noncritical, allow:

• as-fired condition.

This helps keep the part economical.

Hole and Fastener Information

If the component contains bolt holes, provide:

• bolt size;
• washer arrangement;
• expected clamping method.

The ceramic hole should be designed as part of the joint.

Mating Metal Components

If the ceramic fits inside metal hardware, provide:

• mating dimensions;
• material;
• operating temperature.

This allows differential thermal expansion to be reviewed.

Quantity

State both:

• prototype quantity;
• expected production quantity

if known.

A process appropriate for three pieces may not be economical for 3,000 pieces.

Annual Demand

For repeat business, annual volume can influence:

• tooling strategy;
• production method.

A higher initial tooling cost may be justified for long-term production.

Existing Sample

For replacement projects, provide:

• old sample;
• photographs;
• operating history.

But do not rely on the sample alone if it is damaged or worn.

Failure History

If the previous ceramic cracked, tell the supplier.

Useful information includes:

• crack location;
• operating temperature;
• thermal event;
• mounting method.

This allows redesign rather than blind duplication.

Documentation

Define any required:

• TDS;
• composition report;
• COA;
• dimensional report;
• FAI.

Documentation should match project risk.

Inspection Standard

State how acceptance will be determined.

For example:

• dimensions;
• appearance;
• material composition;
• strength.

Do not wait until after delivery to introduce new acceptance criteria.

Prototype Approval

For complex parts, agree whether production begins only after:

• first article;
• prototype approval.

This reduces misunderstanding.

Packaging

Custom ceramic parts may require:

• individual cushioning;
• wooden cases;
• separators.

Provide any special logistics restrictions.

Delivery Location

For accurate commercial quotation, state:

• destination;
• Incoterm preference

where relevant.

Technical evaluation can begin without this, but delivered pricing cannot.

What If No Drawing Exists?

Provide the best available information:

• old sample;
• hand sketch;
• measured dimensions;
• photos with scale.

The supplier can then help convert this into a production drawing.

Avoid “Same as Sample” as the Only Specification

Samples can vary.

A written approved drawing is much more reliable for repeat orders.

The sample can remain a reference, but dimensional and material requirements should be documented.

Engineering Takeaway

A strong custom-ceramic RFQ explains both the component and the environment in which it must work.