Following the death of Friedrich Krupp, his widow Therese Krupp continues the running of the company, supported by her relatives and her then 14-year-old eldest son Alfred. Long and complicated tests are carried out to perfect the production of high-quality crucible steel. In 1830 Krupp begins to supply finish-machined rolls instead of his earlier unfinished rolls as these frequently crack due to incorrect machining by customers. The products are supplied with a guarantee of quality.
From 1833 Krupp manufactures complete rolling machines, initially in limited volumes, but after the customs barriers are lifted by the German customs association in 1834 the customer base is expanded. In addition, the purchase of the first steam engine in 1835 lowers production costs. Both these events boost sales and as a result the manufacturing shops are extended. Trips to other European countries attract new customers.
