Beräkning av optimal batchstorlek på gavelspikningslinjer hos Vida Packaging i Hestra

Sammanfattning: This final thesis aim to create a support that can decrease the uncertainty when planning the cable drum flanges lines that produces cable drums in the interval 100 to 320cm in diameter at Vida Packaging in Hestra. The purpose attains through finding an optimal batch size that minimizes the total storage cost and order prime cost, without degenerate delivery capacity to the customer. Through survey the sale and stock balance development during 2005 and 2006 for cable drums in Hestra and give alternative suggestions how to plan the production after installing a new cable drum flanges line. The study also explores different ways of working during product change in existing nailing line, to minimize the order prime cost. Vida Packaging in Hestra is a part of the Vida group, which is Sweden's largest privately owned sawmill group with seven sawmills placed all around southern Sweden. Apart from the plant in Hestra includes Hong Kong, Ryd, Vetlanda, Vimmerby and Österlövsta in Vida's packaging division. The plant in Hestra produces among others cable drums. The study shows a steady increase in sales volumes under 2005 and 2006. Sales are affected both by seasonal patterns and trend. The stock balance increases during wintertime and the great number off deliveries are made during summertime. To maintain a high delivery capacity during the whole year is it important to base the planning on quantified forecasts. Instead of the way they now base the production plan on subjective estimations. With Wilson's formula every article has been given an calculated optimal batch size to support the planning work. With subjective estimations there is a risk that wrong products are being produced during wintertime which leads to worse delivery capacity during summertime. To minimize the order prime cost requires standardized ways of working by the operators during product changes and not like today where different shifts uses different techniques. By implementation of standardization tools the order prime cost can be reduced and more effective product changes can be done.