You already run the back end
If machining, treatment or riveting is already in your own shop, buying a completed stack pays twice for work you will strip back or repeat. Naming the handover stage in the purchase order removes that waste.
Part family 04 · Brake heat sinks
Carbon brake discs, delivered at the process stage you specify
You do not have to buy a completed heat sink. If your own line covers one or more of the downstream operations, name the handover stage and we build to that point. The stage names and the delivered forms are set out below; the process parameters are not published.
An intermediate stage is not a finished, released part. Output at S1, S2 or S3 is work in progress under your programme. It travels with a certificate of conformity, process records and traceability — not with an airworthiness release tag. Final inspection and the release signature remain with you.
Four handover stages
The same disc, four different places to stop. Which one applies is written into the programme, not assumed at quotation.
Delivery point is chosen by the customer
- S1
At agreed density
Carbon disc brought to the density stated in your specification.
- S2
Machined
Carbon disc machined to the drawing revision you issued.
- S3
Treated
Carbon disc after the anti-oxidation treatment called out by you.
- S4
Riveted
Riveted disc stack or heat sink assembly, with its metallic hardware.
The stage names describe what you receive, not how the operation is run. Processing takes place at qualified partner facilities; the parameters belong to those facilities and to the technical agreement, and are not reproduced on this site or in downloadable material.
What arrives at each stage
Four nodes plus the metallic hardware used in the riveting operation. The right-hand column is what your incoming inspection will actually have to file.
| Stage | What you receive | What you do next | Records shipped |
|---|---|---|---|
| S1 | Carbon disc at the agreed density, with its material and lot record | You machine or process it in your own downstream line | Material certificate, lot and batch record, dimensional blank record |
| S2 | Carbon disc machined to your drawing and revision | You carry out the treatment called out in your process | Dimensional record against the ballooned drawing, first article report where the programme calls for one |
| S3 | Carbon disc after the specified anti-oxidation treatment | You rivet the stack, or ask us to continue to S4 | Process traveller for the operations performed, treatment conformity record, material traceability |
| S4 | Riveted disc stack or heat sink assembly | You carry out final inspection and sign the release under your approval | Assembly and hardware traceability record, certificate of conformity, the complete traveller |
| Hardware | Metallic items used in the riveting operation — rivets, keys, drive lugs, retainers; defined by your drawing | Shipped with the disc set, or separately if your routing requires it | Material certificates and lot traceability for each hardware type |
Hardware is not a separate product line here: it is the set of metallic items your drawing calls for in the riveting operation, supplied to the same revision state as the discs.
Where the line is drawn
Publishing a stage is useful to a customer. Publishing the parameters behind it would only be useful to a competitor.
| Item | Position |
|---|---|
| Published here | Stage names, delivered form at each stage, the documents that travel with the goods, and who signs the release. |
| Not published | Numerical density values, treatment chemistry and thermal profiles, rivet setting values and fixture settings, batch process cards. These stay with the qualified facility and the agreement you sign with it. |
| Who manufactures | Work is carried out at qualified partner facilities in China, to your drawing and under your approval. We select and qualify the process, own the routing and keep the record discipline. The plant is not ours. |
| Who releases | You do. A release document is issued under an approval, by the holder of that approval. We supply records in support of your signature, never a substitute for it. |
Installability is a separate question. Whether a part built under a given approval can be installed on a particular registration is decided by the State of Registry. Adding a brake family to our scope does not change that: any such question still goes through a written release path determination before an order is placed.
Why a holder asks for a stage instead of a finished stack
Three situations where buying the completed assembly is the wrong shape of order.
You want one operation kept in-house
Some holders keep the treatment or the final assembly under their own quality system because that is where their substantiation sits. The stage boundary lets you do that without changing the supply model for everything upstream.
You need the hardware with the discs
Rivets, keys, drive lugs and retainers are defined by your drawing, not by a generic catalogue. Ordering them with the disc set means one revision state, one lot file and one shipment to reconcile.
What you send, what comes back
No stage is booked without the left column. Nothing leaves without the right one.
From you
- Drawing and revision for the disc and for every hardware item
- The stage you want to take delivery at, and the operations you will perform afterwards
- Material, treatment and acceptance callouts, including the test or inspection evidence you require
- The approval the output will eventually be released under
From us
- Output at the stage named in the agreement, to the revision issued
- Certificate of conformity against that drawing revision
- Material, lot and batch traceability; dimensional records for the operations performed
- Process traveller signed at each operation, plus any first article report the programme calls for
Name the stage and send the drawing status
Tell us which operation stays in your shop and which revision you are working to. The first written reply sets out the process route, the document set for that stage and whether the release path works for your registry.