Estimating Job Flow-Times in a Job Shop for Contractually Negotiated Due-Dates

One of the most important aspects of job shop planning is the contract negotiation process. In this process the job shop vendor must negotiate a job due-date acceptable to both job shop and the customer. Failure to obtain reasonably accurate predictions of the job completion time can result in penalties and/or lost future sales for the job shop. As such, estimation of job flow-times is critical to successful job shop operation. This paper presents a network modelling approach to the difficult and complex task of estimating job flow-times not previously presented in the literature. The approach is demonstrated via a case example where the system model is developed as a Q-GERT network and simulation results are obtained.