7.7
Lote Econômico de Compra
Distribuidores comerciais frequentemente enfrentam um dilema entre a frequência de pedidos e a posse de estoque. Fazer pedidos com muita frequência el…
A CleanPro, uma distribuidora comercial de produtos de limpeza, enfrenta custos crescentes de estoque devido a práticas de pedidos ineficientes.
Pedidos pequenos frequentes aumentam as despesas com pedidos, enquanto grandes pedidos em massa aumentam os custos de armazenamento e seguro.
Como resultado, a CleanPro enfrenta custos gerais de estoque mais altos e menor eficiência operacional.
A empresa decidiu aplicar o modelo de Quantidade Econômica de Pedidos ou EOQ para resolver o problema.
Esse modelo determina a quantidade ideal de pedidos que minimiza os custos totais de estoque, incluindo os custos de pedidos e manutenção.
A EOQ é calculada como a raiz quadrada de duas vezes a demanda anual, multiplicada pelo custo do pedido, dividido pelo custo anual de manutenção por unidade.
A CleanPro vende dez mil unidades de um produto por ano.
O custo de fazer um pedido é de cem dólares e o custo anual de manutenção por unidade é de dois dólares.
Usando a fórmula EOQ, a quantidade ideal do pedido é calculada em mil unidades.
O EOQ é mais eficaz quando a demanda é consistente, os prazos de entrega são constantes e os fatores de custo permanecem estáveis.
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Q1: What problem does the Economic Order Quantity model solve for inventory management?
EOQ addresses the cost trade-off between frequent small orders and large bulk purchases. Frequent orders inflate administrative expenses, while bulk orders increase storage, insurance, and capital tied up in inventory. EOQ identifies the optimal order quantity that minimizes combined ordering and holding costs, improving operational efficiency and reducing overall inventory expenses.
Q2: How is Economic Order Quantity calculated?
EOQ equals the square root of twice the annual demand multiplied by the ordering cost, divided by the annual holding cost per unit. For example, if annual demand is 10,000 units, ordering cost is $100, and holding cost per unit is $2, the EOQ formula yields an optimal order quantity of 1,000 units that minimizes total inventory costs.
Q3: What assumptions must hold for EOQ to be effective?
EOQ works best when demand is consistent, lead times remain constant, and cost factors stay stable. However, real business environments often experience seasonal demand fluctuations, bulk discount opportunities, or supply chain disruptions. When these assumptions don't hold, EOQ should be adapted or supplemented with other inventory models to maintain accuracy.
Q4: How do ordering costs and holding costs affect the optimal order quantity?
Ordering costs and holding costs create opposing pressures on order quantity. Higher ordering costs push toward larger orders to reduce frequency, while higher holding costs push toward smaller, more frequent orders. EOQ mathematically balances these competing factors to find the order size that minimizes their combined impact on total inventory expenses.
Q5: Why might Just-in-Time inventory be considered an alternative to EOQ?
Just-in-Time inventory systems minimize holding costs by receiving goods only when needed, contrasting with EOQ's fixed order quantity approach. While EOQ assumes stable demand and costs, just in time inventory works best with reliable suppliers and predictable demand. Businesses may use just in time inventory when holding costs are extremely high or supply chain reliability is strong.
Q6: Should safety stock be used alongside EOQ calculations?
Yes, incorporating safety stock is often necessary even when using EOQ as a foundation. Safety stock buffers against delivery delays and demand variability that EOQ's assumptions don't account for. This additional inventory protects against stockouts when actual conditions deviate from the stable demand and lead times that EOQ presumes.
Q7: How can bulk discounts affect the use of EOQ in practice?
Bulk discounts complicate EOQ because suppliers often offer lower per-unit prices for larger orders, creating incentives to order beyond the calculated EOQ. When significant discounts are available, businesses must compare the savings from bulk pricing against the increased holding costs. EOQ should be adapted or supplemented with quantity discount models to make optimal ordering decisions.