“Tin-plated sheet steel, referred to as tin plate”, commonly known as tinplate, is a low-carbon thin steel plate coated with pure tin on both sides. Tin-plated by hot-dip process is called hot-dip tin-plated plate, and tin-plated by electro-plating process is called tin-plated plate . Mainly used as packaging material for canned food.
I.Tin plate structure and main production process
Tin plate structure consists of steel substrate, tin-iron alloy layer, tin layer, oxide film and oil film.
Composition (see Figure 11). The thickness, composition and performance characteristics of each component are shown in the table.
Figure 1-1 Sectional view of tin plate
1—steel substrate 2—tin-iron alloy layer 3—tin layer
4 oxide film 5 oil film
The main production process of tin plate (see Figure 1-2).
Low carbon steel → hot rolling → slab → hot rolling → strip steel → pickling and cold rolling → electrolytic cleaning → annealing → flattening → trimming
→ Electrolytic cleaning → Pickling → Plating tin → Reflowing → Passivation → Processing oiling → Inspection → Shearing → Classification → Packaging → Plating tin plate → Shearing → Pickling → Flux treatment → Hot dip tin → Cooling → Cleaning → Inspection Classification → Packaging → Hot Dip Tin Plate
Figure 1-2 Main production process of tin plate
The price of tinplate in 2019 increased by 25.45% year-on-year. The price of tinplate (using Shanghai 0.5mm cold-rolled coil) started at the highest price of 6,120 yuan / ton in 2010, and fell unilaterally to 2690 yuan / ton in December 2019, a decrease of 56%. With the increase of environmental protection and production capacity, the price of tinplate began to pick up. The average price in 2019 reached 4,816 yuan / ton, a year-on-year increase of 25.45%. The price before the deadline (January 17, 2019) was 5,100 yuan / ton.
Cold rolled steel coil 0.5mm since 2010: Shanghai price trend (yuan / ton)
Quarterly average price of tinplate since 2014
It is expected that the performance in 2020 is expected to regain growth momentum. In Q1, Q2 and Q3 of 2017, the year-on-year increase in tinplate prices was 52.33%, 11.28% and 33.56%.