EQUIVALENT UNITS; VALUATION OF WORK-IN-PROCESS INVENTORIES; FIRST-IN, FIRST-OUT VERSUS WEIGHTED AVERAGE AKL Foundry manufactures metal components for different kinds of equipment used by the aerospace, commercial aircraft, medical equipment, and electronic industries.

The company uses investment casting to produce the required components. Investment casting consists of creating, in wax, a replica of the final product and pouring a hard shell around it. After removing the wax, molten metal is poured into the resulting cavity. What remains after the shell is broken is the desired metal object ready to be put to its designated use.

Metal components pass through eight processes: gating, shell creating, foundry work, cutoff, grinding, finishing, welding, and strengthening. Gating creates the wax mold and clusters the wax pattern around a sprue (a hole through which the molten metal will be poured through the gates into the mold in the foundry process), which is joined and supported by gates (flow channels) to form a tree of patterns. In the shell-creating process, the wax molds are alternately dipped in a ceramic slurry and a fluidized bed of progressively coarser refractory grain until a sufficiently thick shell

(or mold) completely encases the wax pattern. After drying, the mold is sent to the foundry process. Here, the wax is melted out of the mold, and the shell is fired, strengthened, and brought to the proper temperature. Molten metal is then poured into the dewaxed shell. Finally, the ceramic shell is removed, and the finished product is sent to the cutoff process, where the parts are separated from the tree by the use of a band saw. The parts are then sent to the grinding process, where the gates that allowed the molten metal to flow into the ceramic cavities are ground off using large abrasive grinders. In the finishing process, rough edges caused by the grinders are removed by small handheld pneumatic tools. Parts that are flawed at this point are sent to welding for corrective treatment. The last process uses heat to treat the parts to bring them to the desired strength.

In 2007, the two partners who owned AKL Foundry decided to split up and divide the business. In dissolving their business relationship, they were faced with the problem of dividing the business assets equitably. Since the company had two plants—one in Arizona and one in New Mexico—a suggestion was made to split the business on the basis of geographic location. One partner would assume ownership of the plant in New Mexico, and the other would assume ownership of the plant in Arizona. However, this arrangement had one major complication: the amount of WIP inventory located in the Arizona plant.

The Arizona facilities had been in operation for more than a decade and were full of WIP. The New Mexico facility had been operational for only two years and had much smaller WIP inventories. The partner located in New Mexico argued that to disregard the unequal value of the WIP inventories would be grossly unfair.

Unfortunately, during the entire business history of AKL Foundry, WIP inventories had never been assigned any value. In computing the cost of goods sold each year, the company had followed the policy of adding depreciation to the out-ofpocket costs of direct labor, direct materials, and overhead. Accruals for the company are nearly nonexistent, and there are hardly ever any ending inventories of materials.

During 2007, the Arizona plant had sales of $2,028,670. The cost of goods sold is itemized as follows:

Direct materials $378,000 Direct labor 530,300 Overhead 643,518 Upon request, the owners of AKL provided the following supplementary information (percentages are cumulative):

Costs Used by Each Process as a Percentage of Total Cost Direct Materials (%)
Direct Total Labor Cost (%)
Gating 23 35 Shell creating 70 50 Foundry work 100 70 Cutoff 100 72 Grinding 100 80 Finishing 100 90 Welding 100 93 Strengthening 100 100 Gating had 10,000 units in BWIP, 60 percent complete. Assume that all materials are added at the beginning of each process. During the year, 50,000 units were completed and transferred out. The ending inventory had 11,000 unfinished units, 60 percent complete.
Required:
. The partners of AKL want a reasonable estimate of the cost of WIP inventories.
Using the gating department’s inventory as an example, prepare an estimate of the cost of the EWIP. What assumptions did you make? Did you use the FIFO or weighted average method? Why? Round unit cost to two decimal places.
. Assume that the shell-creating process has 8,000 units in BWIP, 20 percent complete. During the year, 50,000 units were completed and transferred out. (All 50,000 units were sold; no other units were sold.) The EWIP inventory had 8,000 units, 30 percent complete. Compute the value of the shell-creating department’s EWIP. What additional assumptions had to be made?