1. Frame materials of Qingdao iron gates

(1）. In recent years, the frames of Yantai iron gates are made of rectangular tubes or square tubes. Sliding doors use 

more rectangular tubes, and iron swing doors use more square tubes. Among them, square tubes sometimes use 

embossed square tubes (square tubes with process indentations on the four edges).

（2）. In the early years when iron art just emerged, solid square steel frames were mostly used. With the development 

of iron art, through feedback from actual construction operations. Small-sized square steels are gradually no longer

 used, and even solid square steel materials are large-sized square steels.

In short, the most commonly used material for the frames of iron gates/iron gates is hollow square tubes. Because

 square tubes are not easy to deform, and their anti-deformation strength is much greater than that of solid materials 

of the same weight. On the other hand, under the same external dimensions, the cost of hollow square tubes is much

 lower than that of solid square steel.

2. Inner frame and inner beam of wrought iron door/Qingdao wrought iron gate

（1）. Common materials for inner frame and beam of wrought iron door/wrought iron gate include square tube, 

rectangular tube, flat iron and embossed flat iron.

（2）. Square tube and rectangular tube are more stable, but the disadvantage is that the internal vertical support needs 

to be disconnected twice. The processing cost is slightly higher. The characteristics of flat iron and embossed flat iron

 are strong sense of craftsmanship, and the internal vertical support can be made of one piece of material without 

disconnecting twice. The disadvantage is that it is difficult to spray the inside of the two flat irons in place, which 

may bring hidden dangers to rust and corrosion prevention in the later stage.3. Vertical support of wrought iron gate/Qingdao wrought iron gate

（1）. It is still composed of two types. In addition to the square tube material we are very familiar with, it is the solid 

material type. The solid material is divided into: square steel, embossed square steel, round steel, embossed round 

steel, special-shaped steel, thick flat steel, etc.

（2）. The characteristics of square tube materials are that the visual effect is heavy and the structure is stable. The 

characteristics of solid materials are still strong sense of craftsmanship and better effect.

4. Internal flower pattern of wrought iron gate/Qingdao wrought iron gate

（1）. In a few cases, the internal flower pattern will use square tube shape, such as circle, diamond and other geometric 

shapes. In most cases, round steel, embossed round steel, square steel, embossed square steel, flat iron, embossed flat 

iron and other materials will be used.

（2）. In terms of deformation difficulty, it is square tube>square steel embossed square steel>round steel/embossed round 

steel>flat iron/embossed flat iron.

（3）. In addition, cast iron flowers were used in a large number of mainstream wrought iron gates in the past few years.

5. Accessories of wrought iron doors/wrought iron gates in Qingdao

（1）. Accessories of wrought iron doors/wrought iron gates are divided into: malleable cast iron parts, precision castings, 

stampings, and forgings.

（2）. Most of the spear tips are forged parts, that is, parts that need to be heated and processed. The second most widely 

used are stamping parts, which have strong processability but low prices. In recent years, other precision castings and 

malleable cast iron parts have gradually decreased.