Screws, Nuts

Preparing the wire rod is the first step in manufacturing bolts. Factory operators check the material and dimensions of the wire rod against the process instructions and prepare molds and inspection tools before forging the bolt heads. The first piece of coil is inspected after calibrating and adjusting the forging machines, and three samples are inspected every 15 minutes. Data is recorded in an independent inspection form every two hours. After forging is completed, a process label is attached to each tub of bolts. The next step is the milling of threads: Before the process of milling threads starts, operators must prepare molds and inspection tools, and then check the workpieces against the process instructions. As in the previous process, the machines are first calibrated and adjusted, the first piece is inspected, three additional pieces are inspected every 15 minutes, and data is recorded in an independent inspection form once every two hours. One process voucher is released after each batch of bolts is completed. Depending on the type of product, the bolts may afterwards be sent for rust-proofing or heat treatment, or directly sent to the packaging department for packaging and storage.