An acceptance plan for an automated bonding assembly line is a document, not a punch list. It says what the line has to be able to do before anyone signs it off, how each requirement will be demonstrated, who attends the demonstration, and what happens to anything that fails. On this site the line category sits under automated production line solutions, and the bonding machines that a line integrates sit under semiconductor process equipment. That split matters when the plan is written, because the line has to be accepted as a system even though it is assembled from individually documented stations.
Why a line needs a different acceptance plan from a single machine
A single bonding station is accepted against its own behaviour: does it align, does it bond, does it hold the process it was bought to hold. An automated bonding assembly line adds everything that only appears once stations are wired together. Handoff between stations, the stop logic that one station sends to its neighbour, what happens to work in progress when one station is paused for a changeover, whether a recipe change at the front of the line reaches the back of it correctly, and whether the whole line can be restarted after a stop without a manual sweep for damaged parts. None of these can be tested on an isolated machine. They are the reason a line acceptance plan is mostly about interfaces, and why copying the acceptance section of a machine datasheet onto a line purchase leaves the riskiest behaviour untested.
There is a second reason the plan has to be written early. The people who will be asked to sign the line off are the same people who had to answer questions during the quotation. If the acceptance plan is written after the order, it inherits the wording of the sales material instead of the wording of the requirement. Written before the order, it becomes the test the quotation is measured against.
What the plan has to cover, section by section
Six blocks recur in acceptance plans that hold up in practice. The first is scope: which stations are inside the acceptance, which are supplied by others, and where the boundary sits in the physical line. Ambiguity here is the most expensive kind, because a station that is nobody's responsibility in the plan becomes a disputed item at handover.
The second block is the product the line is being accepted on. A bonding line is not accepted against a generic part. The plan names the part or film stack, its dimensions and datums, and who supplies the samples used in the acceptance run. A line accepted on supplier samples that do not match the buyer's production part has been accepted against something the buyer does not make.
The third block is the requirement list, written as behaviour rather than as adjectives. Each entry names what the line does, the condition it does it under, and how the result is read. Entries that say the line should be stable, precise or reliable cannot be demonstrated and should be rewritten until they can. Each entry is marked as measured or judged, because a measured entry has a reading and a judged entry needs a named person and a stated criterion, and mixing the two quietly is how acceptance meetings stall.
The fourth block is the demonstration itself: where it happens, how long the line runs, what is deliberately excluded, and how many consecutive runs are required. A short demonstration at one speed proves far less than a run that crosses a changeover and a restart. The plan fixes the run length and the run contents before anyone travels to watch it.
The fifth block is the evidence that leaves the demonstration: the recorded parameters, the fault log, the inspection result, the list of items that did not pass and what closes them. The sixth block is the signature page, naming the people who accept each block and the date their acceptance covers. A plan without named signatories is a checklist that nobody owns.
Block of the plan
What it has to answer
Scope and boundary
Which stations are inside, which are supplied by others, where the handover boundary sits
Product and samples
Which part or stack the line is accepted on, who supplies it, what datums apply
Requirement list
Behaviour, condition, reading method, and whether each entry is measured or judged
Demonstration
Where, for how long, with what excluded, including a changeover and a restart
Evidence pack
Recorded parameters, fault log, inspection result, open items with owners
Signature page
Who accepts each block, what the acceptance covers, what it does not cover
The line-level items buyers most often forget to write down
Interface behaviour is the first. The plan should state what each station does when the next one is full, when the previous one is empty, and when the line is stopped mid-cycle. These are questions about buffers, signals and recovery, and they are settled by watching the line, not by reading a specification.
Recipe and program control is the second. A line that bonds different products needs acceptance for switching between them: who can change a recipe, whether the change is confined to one station or propagates, and what happens to the parts already on the line when a switch happens. Buyers who buy one product today should still write this down, because the second product is usually where the line is blamed for a design decision made at quotation.
Process data and traceability is the third. The plan should say what the line records, in what form, and how long it is kept, since a line that cannot show which station produced which result cannot support a quality investigation later. Integration with the buyer's own systems belongs here too, and it is the single most common source of a delayed acceptance, because it is the item most often assumed rather than agreed.
Training and spares are the fourth. An acceptance plan that stops at the demonstration leaves the buyer with a line nobody on the shop floor was trained against. The plan should include the training record and the spare-parts list with part numbers as acceptance items, not as a later commercial conversation.
Figures: what the plan can and cannot be built on
Some entries on this site's equipment pages publish numbers, and some do not. The bonding line pages in particular list the line without a parameter block. That has a direct consequence for the acceptance plan: any figure the plan relies on has to come from a written statement tied to the machine actually being bought, together with the condition under which it was obtained. A number taken from a neighbouring machine in the same category is not evidence about this line, and importing one into an acceptance document converts a marketing figure into a contractual one, which is the worst direction for that kind of error to travel.
Where a figure does exist, the plan should record the condition beside it. A rate measured on one part at one speed is not the rate of a line running a different part with a different changeover pattern. Writing the condition next to the figure is what lets both sides argue about the condition instead of arguing about the number.
Where a figure does not exist, the plan should leave it as an open item rather than fill it with an estimate. A blank cell with an owner and a date is honest; a guessed number that later appears in a business case is not.
How the plan is used when comparing suppliers
Send the same acceptance plan to every supplier in the comparison and ask each one to complete it: what they can demonstrate, what they cannot, what needs a longer run than the plan allows, and what they treat as excluded. A supplier who completes it line by line is giving a comparable answer. A supplier who returns a brochure instead has answered a different question, and that difference is usually worth more than the gap in quoted price.
This is also where the plan stops being a document about the future and becomes a negotiation tool in the present. Entries the supplier marks as not demonstrable are exactly the entries that need either a change of scope or a change of price, and finding that out before the order is the cheapest moment to find it out.
Before the plan goes out
A short review of the draft prevents most of the arguments that appear later. Four questions are enough: is every requirement written so that a person watching a run could say yes or no to it; is each one marked measured or judged; is there a named acceptance owner for every block; and is there anything the plan is silent about that the shop floor will care about on day one, such as changeover, restart after a stop, and who holds the program rights after handover. A plan that survives those four questions will usually survive the acceptance itself.
If the line is being scoped rather than accepted, that is the stage where this plan is cheapest to write. The customized steam cleaning equipment route on this site is where the buyer's requirement description is sent for a first technical answer; the discipline is the same for a production line: state the product, the boundary, the protected items and the acceptance wording before the quotation, and ask for the same list back in writing.
