Build an Inspection and Test Plan with Clear Hold Points

A machined surface is ready for inspection, but coating will soon make part of that surface harder to examine. The order says the buyer may witness inspection, yet it does not say how much notice is required, whether work may continue after a missed visit, or who can release the next operation. That is an incomplete control point, even if the inspection itself is technically sound.

Build the inspection and test plan (ITP) around the actual order and manufacturing sequence. Each control line should identify the characteristic, the governing document and revision, the acceptance basis, the method, the record, the responsible and verifying roles, the inspection point, the notification rule and the release authority. A blank, unknown or conflicting item remains open; it is not evidence of acceptance.

Translate order requirements into process steps

Begin with the controlled order package: the purchase order, contract quality clauses, approved drawing list, specifications, bills of material, approved procedures and any standards expressly incorporated into the order. Record the document number and revision that apply. Do not select a requirement merely because its file date is newest, and do not assume that a familiar standard overrides the purchase order. If two approved documents conflict, identify the conflict and send it to the role authorized to establish precedence.

Next, map the route the part will actually follow. For an undercarriage component, that route might include material receipt, traceability transfer, machining, an applicable treatment, inspection before coating, coating, marking, final inspection and record-package review. Include an operation only when it belongs to the part and order. A pressure-vessel or structural-welding template can suggest fields, but its process steps, tests and inspection points do not become requirements for a track roller, idler or sprocket.

The AMREP manufacturing ITP guide describes the same basic method: collect the product requirements, map the production sequence, then define the inspection method, criterion, roles and record at each selected stage. Use that as planning guidance, not as a substitute for the order's technical documents.

Mark the interfaces where evidence can be lost or a condition becomes inaccessible. Examples include transferring a heat or lot identity into a machined blank, verifying a finished dimension before assembly, or examining a surface before coating. Place the control before the irreversible step. Then ask four questions for every candidate point:

• What characteristic or document is being verified?
• Which approved requirement defines acceptance for this order?
• What evidence will show the result and connect it to the affected part or lot?
• Who may decide that the next step can begin?

If any answer is unknown, keep the candidate point open during ITP approval. Manufacturing convenience does not close a requirement gap.

Define each inspection line

Write one line for one controllable event. Split a broad label such as “machining inspection” when different characteristics use different methods, records, frequencies or release roles. Conversely, do not split identical checks just to make the plan look detailed. The row boundary should follow a real change in what is checked, how it is judged or who controls progress.

Each line needs enough information for a qualified person who did not draft the ITP to perform or verify the activity:

• Step and characteristic: name the operation and the feature, identity, document or condition being checked.
• Basis and revision: cite the applicable drawing, specification, procedure or contract clause with its controlled revision. Put the measurable criterion or an exact acceptance reference next to it.
• Method and extent: state how the check is made and the approved inspection frequency or sampling basis. “Check dimension” and “as required” are not executable instructions.
• Record: name the report, certificate, log or release record, including its form revision when applicable, and define how it links to the part, serial number, heat or lot.
• Responsibility: name the role that performs the work and the separate role that verifies or releases it. Use roles rather than personal names where personnel may change.
• Point, notice and release: identify H, W or R; state the agreed notification or submission rule; and name the authority and evidence needed before progress.

The Jags Assurance guide to preparing an ITP recommends a scope-specific sequence, a governing clause, acceptance criteria, roles and a named record for each activity. Its examples come from its project-quality practice. The order team still has to select the requirements and roles that apply to this part.

The following original example shows the level of definition, not a KTSU test record or a ready-to-use specification. All identifiers are fictional, and the acceptance values remain in the named hypothetical order documents.

A “pass” in the outcome column should mean that the recorded result met the cited criterion under the stated method. It does not repair a missing source revision, authorize a deviation or grant shipment release. Those are separate decisions with their own evidence.

Distinguish hold, witness and document review

A hold point stops progress beyond the identified stage until the designated authority has released it in the agreed form. A witness point gives a designated party the opportunity to attend an inspection or test. Whether work can continue if that party does not attend depends on the contract and approved ITP. A review point calls for examination of a document or record; the letter R alone does not say whether the review must be completed before the next operation.

Keep the point type separate from the evidence state. “W” does not mean witnessed, “R” does not mean reviewed, and “H” does not mean released. Record what actually happened: notice sent, notice acknowledged, attended, waived, reviewed, accepted, rejected or still pending.

In the illustrative pre-coating sequence, the buyer and supplier chose a witness opportunity for the physical inspection and a separate hold point before coating. Another order could combine or change those controls. The decision belongs in the applicable contract and approved ITP because coating accessibility, technical risk, inspection arrangements and commercial responsibilities differ.

Notification windows

Do not copy a supplier, consultant or previous project's notice period into a new order. Define the window in the contract or approved ITP and make it operational. State the event that starts the clock, the amount and unit of notice, business-day and holiday treatment, time zone, recipients, required notice contents, acknowledgement method, rescheduling or cancellation rule, and what happens if the invited party does not attend.

A useful notice identifies the purchase order, part and lot, ITP line, activity, location, planned date and time, contact, and the records that will be available. If the activity moves, preserve the original notice, the change communication and the revised appointment instead of overwriting the history.

As a narrow buyer-specific example, Sulzer Quality Specification 40-554, Rev. 2 tells suppliers assigned witness or hold points to use the notification period in the purchase order or associated documents and lists information to include in an inspection notice. That document governs the specified Sulzer purchase context. Its timing and consequences are not general rules for an undercarriage-parts order.

Release authority

Name the role that can release each hold point, the form of acceptable evidence, the exact scope released and any permitted delegation. A message such as “looks good” is ambiguous unless the agreed process recognizes the sender, record and affected lot. A release for one lot or operation should not silently release another.

Also identify who can approve a deviation or concession. An inspector can record a result without necessarily having authority to change an acceptance requirement. If a result fails, a document revision conflicts, or the release role is unknown, stop the affected progression and route the issue to the designated authority. A witness party's absence is not a hold-point release, and a supplier's internal approval is not a buyer release unless the agreement explicitly makes it so.

The AMREP explanation of hold, witness and review points likewise states that witness non-attendance may allow progress only under agreed procedures and depending on the contract. Record the order's actual rule instead of relying on the label alone.

Control changes and keep the completed records

Give the ITP a document number, revision, issue date, approval status and effective scope. When the drawing, procedure, inspection extent or point assignment changes, record what changed and which purchase-order lines, quantities, lots or serial numbers are affected. Do not replace the old file and leave completed rows without a traceable basis.

For work already performed, preserve the ITP revision used, the source-document revisions cited by its rows, the actual results and the release evidence. For work not yet started, issue the approved revision and record its effective boundary. If a conflict is found between a row and its source document, the safe status is open until the authorized parties resolve the discrepancy and decide whether earlier work needs review.

The completed record set should retain the actual inspection date, result, part or lot identity, required equipment or certificate references, performer and verifier roles, notices, attendance or waiver records, hold releases, nonconformance references, approved dispositions and attached reports. The exact contents and retention period come from the order and applicable quality system.

Three short walkthroughs test the logic of the illustrative ITP:

• Normal: every row cites an approved revision, the required records match the lot, notice and attendance outcomes are recorded, and the named authority signs each required release. The record set is complete for handover, subject to that authority's decision.
• Missing: the witness row has no no-attendance rule, or the pre-coating release reference is blank. The affected operation remains open; silence does not become permission.
• Conflict: the drawing field says Rev. C while the inspection procedure or completed report identifies Rev. B without an approved relationship. The row remains open until the discrepancy is resolved and its effect on the lot is recorded.

When preparing a wider order package, the bulk excavator-parts sourcing guide covers the adjacent supplier and purchasing task. For the ITP itself, finish by reconciling every open field and conflict, freezing the approved revision for its stated scope, and handing the controlled plan to production with its release roles intact.