With the rapid development of national economy, hydraulic technology is increasingly used in metallurgical equipment in China. But currently used for metallurgical equipment Hydraulic cylinder There are many varieties, different models and specifications, and diversified structures, which bring many difficulties to design, manufacturing, and user maintenance. For this“ Hydraulics and Pneumatics Group of the Chairman of the Academic Committee of Metallurgical Equipment of the Chinese Society of Metals” At the 1982 annual meeting, it was decided to design and trial produce standard hydraulic cylinders for metallurgical equipment, which are required to comply with the installation and connection type of series hydraulic cylinders in the international standard ISO6020/1-1981.  

（1） Technical characteristics

1. Pressure: This standard cylinder has two pressure poles, E and G. E pole is applicable to hydraulic cylinders with pressure range of more than 6.3MPa~16Mpa (referred to as Class E cylinder for short). G pole is applicable to hydraulic cylinder with pressure range ＞ 16Mpa~25Mpa (referred to as G pole cylinder for short)

2. Sealing: YX type polyurethane seal ring with simple structure and good wear resistance and YX type rubber seal ring with wide application range are used for Class E cylinder. The G pole cylinder adopts a V-shaped combined seal ring that is resistant to high pressure and has reliable sealing.

3. Anti pressure: the hydraulic cylinder adopts polyamine grease or nitrile rubber frameless dust ring.

4. Applicable media: hydraulic oil, mechanical oil, emulsion. Suitable for phosphate grease.

5. Applicable temperature: - 40 ℃~+120 ℃.

6. Structure: This standard cylinder is equipped with 17 cylinder diameters (40, 50, 63, 80, 90, 100, 110, 125, 140, 150, 160, 180, 200, 220, 250, 280, 320) to form 34 specifications according to two speed ratios (1.46, 2). It is divided into two structures with clearance and slow balance, and the 34 specifications mentioned above form 68 varieties, which is convenient for users to choose at will.  

Both the cylinder head and the cylinder tail are equipped with one-way air release valve, which can be used for quick start and air release of hydraulic cylinder with clearance and balance.  

The rod dust seal adopts replaceable structure, which is convenient for on-site maintenance.  

The piston rod is plated with protective inscriptions, which are dust-proof, rust proof, anti-corrosion, wear-resistant and other characteristics.  

Metric fine thread shall be adopted for the oil port of hydraulic cylinder with cylinder diameter ≤ 220mm.  

The oil port of the hydraulic cylinder with the cylinder diameter ≥ 250mm adopts the seal open flange.

7. Installation and connection: comply with the installation and connection dimensions of series hydraulic cylinders in the international standard ISO6020/1 -/1981. Different cylinder diameters have basic types, front and rear rectangular flanges, front and rear flanges, front and rear round flanges, front, middle and rear pin shafts, and head single earrings; There are 13 installation types of axial and radial feet. (See model description and Table 5-17 for details) The installation and connection dimensions shall comply with ISO6020/- 1981 except for the axial tripod type. The rod end thread also conforms to GB2350-80.