This your choice. Some customers believes that they have a stronger negotiation position if they finalize SLA discussion prior to investment. Some appreciate to get guaranteed uptime also during the warranty period. Others wants to avoid establishing a spare stock and avoid to expend internal organization by signing a SLA early. The warranty in general covers issues during warranty. Preventative maintenance is still needed to start directly and go on also during the warranty period.
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The production of high-performance heat exchangers for aerospace applications

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