From Specification to Commissioning: How a Turnkey Plant Project Really Unfolds

Getting a turnkey production plant is more than placing an order. It is a project that runs over months, passes through several phases and needs coordinated participants on both the supplier and the customer side. Anyone who has been through such a project knows that it is not the individual components that decide success, but the clean transition between phases. In this article we show how a typical plant project unfolds with us, which milestones are decisive and where you, as the client, have to play your part.

Phase 0: First conversation and concept clarification

Before anything is designed, we clarify what is actually needed. That sounds self-evident, but it is not. In many cases customers arrive with a fixed idea ("We need a packaging machine with 60 cycles per minute") and during the conversation it turns out that the real problem lies elsewhere ("We lose throughput because the upstream station does not run in sync").

In the first conversation we mostly listen. Which product is to be manufactured, in what variant diversity and in what quantity? Where are today's bottlenecks? Are there restrictions at the site (ceiling height, available utilities, foundation)? What are the non-negotiable requirements and what would be nice to have?

From this conversation a first concept emerges, often as a sketch plus description. Depending on complexity, this phase lasts one to four weeks and ends with a documented concept that forms the basis for the quotation.

Phase 1: Specification and quotation

From the concept comes a requirements specification (Lastenheft) that the customer and Tomasic agree on together. The specification describes what the system has to be able to do, not how it is technically realised (that comes in the functional specification, later). Typical contents: performance data (throughput, accuracy, availability), product data (specifications, tolerances), interfaces to upstream and downstream systems, operating concept, requirements for hygiene, safety and energy.

We recommend furnishing the specification with clear acceptance criteria. What is measured, with what, under which conditions? If the system is to deliver 60 cycles per minute, for example, it must be clear: measured over what period, with which product variant and at what availability. Otherwise differences arise later between supplier and customer that could have been avoided.

The quotation is based on the specification. It contains the technical scope of performance, the scope of delivery, the schedule, the payment plan and the acceptance conditions. This is where it is decided whether the project comes about.

Phase 2: Engineering and functional specification

With the order, the engineering phase begins. Our designers translate the specification into a technical solution. This phase is the longest in the project, two to six months depending on complexity.

In the functional specification (Pflichtenheft), which is created early in this phase, we document how we will technically solve the requirements. Which components are used, which control logic, which mechanics, which materials. You as the customer receive the functional specification for approval. This is the last opportunity to request changes without major cost.

In parallel with detailed design, orders for long-lead components are placed. Servo drives, special sensors and some bearings have delivery times of 12 to 20 weeks. If this is not initiated early, the overall project schedule later hangs on it.

The engineering phase ends with a design review in which we go through the final drawings, the hydraulic and pneumatic schematics, the electrical design and the control logic with you.

Phase 3: Manufacturing in-house

With the released design documents, manufacturing begins. We manufacture in-house in Niederstotzingen: steel construction, welded assemblies, stainless steel structures, machining. Components we do not produce ourselves (purchased drives, controllers, sensors) are mounted and prepared in this phase.

This phase is quiet from the outside because it takes place in our workshop. We report regularly via status reports, weekly or biweekly depending on project size. You see photo updates, milestones and any shifts early enough to react.

Manufacturing takes two to eight months depending on the system. For large systems it overlaps with the end of the engineering phase because parts are produced in parallel.

Phase 4: Pre-assembly and FAT

Before the system comes to you, it is set up at our premises. We marry steel construction, mechanics, drives, control system and operating interface into a functioning system and run it under conditions as realistic as possible.

If your system processes products, we organise test material. If the system is to have specific interfaces to your IT, we simulate the connection. The goal: the system should run at our site before it is set up at yours.

Pre-assembly concludes with the Factory Acceptance Test (FAT). You come to us with your team, we go through the acceptance criteria together, run the system under load and document the result. Defects are remedied on site or documented with a clear fix plan. The FAT is an important psychological and contractual moment: you see the system working before it is shipped.

Phase 5: Disassembly, shipping, on-site assembly

After a successful FAT, the system is dismantled into transportable modules and delivered to you. For large systems this is a logistical operation with heavy transport, special vehicles and a crane. We plan the logistics as well, so that on day X everything is on site at the same time.

On-site assembly at your premises takes one to six weeks depending on complexity. We bring the fitters and commissioning engineers who were already involved in the pre-assembly. This keeps the knowledge about the system in the minds in which it was built up during the project.

Phase 6: Commissioning and SAT

With assembly, the system is not yet in operation. Commissioning follows: adjustment, trial run, optimisation. For systems in the food industry, cleaning validations are also required; for safety-relevant systems, safety acceptances.

It concludes with the Site Acceptance Test (SAT), the counterpart to the FAT, now on site. Here we demonstrate that the system does what was agreed under your real production conditions. The SAT is the precondition for final acceptance and handover into production operation.

Phase 7: Service, training, warranty

With acceptance, the warranty period begins, usually 12 to 24 months. We operate an after-sales service with spare-parts supply, remote maintenance and on-site service. Training for your operating team and your maintenance staff is part of our scope of delivery.

What many underestimate: a special-purpose machine is in service for 10 to 25 years. The relationship between machine builder and operator is long-term. We invest accordingly in service quality, spare-parts stocking and modernisation options, so that you have a reliable partner over the entire service life of the system.

Where you have to participate as the customer

A turnkey system is not "you order and we do everything". We need your participation at three points in particular.

First, with the specification. If you cannot clearly say what the system is supposed to achieve, even the best engineering cannot develop with precision. Invest time here.

Second, with approvals. Functional specification, design status, interfaces – all of this needs your decision within a manageable time window. Delays here push the project end back by the same amount of time.

Third, in the on-site phase. Connections have to be prepared, personnel available, product samples on hand. If that is not in place, a well-practised commissioning team is left waiting, and that gets expensive.

How long does a project typically take

There is no blanket answer, because the range is enormous. But as rough guidance: a medium-sized special-machinery project typically runs from order to acceptance in 9 to 14 months. A turnkey large-scale plant can have a duration of 18 to 30 months. Anyone assuming shorter times should look very closely at what is excluded from the quotation.

If you have a concrete project ahead of you or first want to understand what lies ahead, get in touch. An initial conversation is non-binding and quickly creates clarity.