During the Anti-Japanese War, Industry Started from the Loess Plateau

What does it take to build a gun? Iron ore starting from raw materials, iron making, steel making, rolling, seamless steel pipe rolling, machining, rifling, 1. Raw material stage -Iron ore mining: open-pit/underground mining of hematite and magnetite, pre-processed by crushing, screening, magnetic separation, and sintering; equipment: excavator, crusher, screening machine -Coal coking 2. Iron and steelmaking stage -Blast furnace ironmaking -Open hearth steelmaking -Electroslag remelting 3. Billet rolling stage -Breaking rolling: steel ingots are rolled into square billets, round billets, and slabs; equipment: two-roller reversible blooming mill -Seamless steel pipe, perforation equipment: perforator, continuous pipe rolling machine, sizing machine -Profile plates: rolled round steel, flat steel, steel plates; equipment: profile rolling mill, plate rolling mill 4. Core manufacturing stage -Heat treatment: ​ -Machining: barrel turning, deep hole drilling and reaming; rifling adopts broaching method (Germany-Soviet) or single-point cutting method (British and American); receiver milling and boring; equipment: lathe, deep hole drilling machine, rifling broaching machine, milling machine ​ -Surface treatment: mainstream blue and rust-proof, later part of the barrel is chrome plated 5. Assembly and inspection stage -Wood parts processing, spring and small parts manufacturing ​ -Dimensional inspection, functional testing and 10-20 rounds of test firing after final assembly ​ -Mauser 98k: In 1943, the working hours per unit were 40-50 hours; the annual production of 100,000 units required 150 lathes, 80 milling machines, and 10 rifling broaching machines. What do we have?