Supplier site visits: what a walk through the plant tells you that a document pack cannot

A visit and an audit are not the same instrument

An audit tests a management system against defined criteria, follows a protocol and produces findings. A visit is broader and less formal: it gathers impressions, builds a relationship, tests whether the commercial story matches the physical reality, and lets you meet the people who will answer the phone at a bad moment. Confusing the two wastes both. Arriving with an audit checklist for what was billed as a relationship visit puts the supplier on the defensive; arriving with nothing prepared for what should have been an assessment produces a pleasant lunch and no information.

Decide what you are trying to find out before you travel

Write down the questions the trip must answer and what evidence would settle each one. Capacity questions need to be answered by looking at machine utilisation, shift patterns and the order board, not by a statement in a meeting room. Capability questions need to be answered at the machine that will run your part. Continuity questions need conversations with more than one person. Send the agenda in advance, including who you need to meet and what you want to see running, and say explicitly that you want time on the floor rather than in the boardroom.

What the shop floor reveals that paperwork hides

Look at the things nobody stages: how much work in progress is sitting between operations and whether it is identified, where rejected material goes and how much of it there is, whether gauges at the workstation carry current calibration labels, whether maintenance records on a machine match its condition, whether operators are working to the instruction posted beside them. Ask an operator what happens when a part measures out of tolerance, and compare the answer with the procedure. A plant that is clean but has no visible measurement activity is a plant where inspection happens elsewhere, if at all.

Following the chain past your supplier's gate

Ask where the material comes in from and where it goes for any outside operation, then arrange to see at least the critical ones. Heat treatment, plating, painting, casting and specialist testing determine properties that your own goods inward inspection will never detect, and they sit with firms you have no contract with. A supplier reluctant to identify or introduce its sub-tier is either protecting a commercial position or hiding a weak one. Even a short visit to a subcontractor changes what you know, and it changes how seriously that subcontractor treats your part.

The follow-up that turns a visit into a decision

Write the notes on the journey home while the detail is fresh, and send the supplier a short summary of what was agreed with dates and owners. Separate observations into things that must change before award, things to improve during the relationship, and things that were simply informative. Circulate it internally so engineering, quality and purchasing hold the same picture rather than three private impressions. A visit with no written output is an expense; the record is what makes the next visit shorter and the next decision defensible. Diarise the agreed actions in your own system rather than trusting the supplier to remember them.

Frequently asked questions

Can a video walkthrough replace visiting a supplier in person?

It replaces part of it. A live, unedited walk with the camera going where you direct it is genuinely useful for confirming that equipment exists, that a part is running and that the building matches the description. What it cannot give you is the ambient information — noise, smell, how people behave when a manager is not talking, what is happening in the corner of the shop nobody turned toward. Use remote sessions for routine contact and reserve travel for award decisions and problems.

Should we announce a visit or turn up unannounced?

Announced visits get you the people you need to meet and the access you asked for, which is usually worth more than the element of surprise. Unannounced visits are appropriate where there is a specific reason to doubt what you have been told, and they will be read as distrust, so use them deliberately. A middle route works well with established suppliers: announce the day but not the detailed agenda, and ask on arrival to see something that was not on the plan.

Who from our side should go on a supplier visit?

At minimum, someone who can assess the process and someone who owns the commercial relationship, because each notices different things and the combination prevents a purely technical or purely commercial reading. For a new source of a complex part, add the engineer who owns the design. Keep the group small enough to move around a shop floor and split up where possible, since two people talking to different staff learn more than a group being escorted along a fixed route.