Metallurgy
Our rich experience in the research and development of sealing materials and advanced sealing processing technology make us a reliable partner in all walks of life. The metallurgical industry is the industry that converts iron ore or scrap steel into steel products, and it has special requirements for sealing solutions. The sealing system used in the blast furnace and other equipment must be able to withstand very high temperatures; the hydraulic system needs to provide 700kg or even higher pressure during the process of pressure processing and forging; the linear speed of the rotating shaft used in the rolling mill and the continuous casting plant It can reach 30 meters per second.
Working medium
The working medium of the seal used in metallurgical equipment is more or less corrosive, so the sealing material will leak slowly after a long time of erosion and lose its sealing effect. In order to reduce accidents caused by the flammability of the medium, more and more flammable working media such as mineral oil are gradually replaced by flame-resistant media.
Anti-combustion media can be roughly divided into the following two categories:
· Water-based medium
· Synthetic media
Water-based media can be divided into high water-based media (HWB media) and low water-based media (LWB media) according to the level of water content. Their chemical compositions are shown in Table 1:
Medium Type | Name | Water Content (%) | Other Components |
HFA-E | Water-in-oil emulsion | 90~98 | Mineral oil, emulsifier, stabilizer, corrosion inhibitor, etc. |
HFA-S | Synthetic medium aqueous solution | 90~98 | Synthetic medium, antioxidant, corrosion inhibitor, anti-gelling agent |
HFB | Oil-in-water emulsion | Approximately 40% | Mineral oil, emulsifier, stabilizer, corrosion inhibitor, etc. |
HFC | Water-ethylene glycol solution | 35~50 | Ethylene glycol, corrosion inhibitor, various additives |
| Table 1: Classification of Water-Based Media | |||
| Medium Type | Name | Toxicity | Remarks |
| HFD-R | Phosphate esters of different grades | Medium/High | Dangerous |
| HFD-S | Chlorinated hydrocarbons | High | Dangerous |
| HFD-T | Mixture of phosphate esters and chlorinated hydrocarbons | High | Dangerous |
| HFD-U | Synthetic ester/silicone ester | None/Low | Biodegradable |
| Table 2: Classification of Synthetic Media (HFD) | |||
In order to avoid damage to the equipment caused by high temperature, the maximum working temperature of these water-based media shall not exceed
60 ℃.
For higher temperature applications, synthetic media may be used. The performance is shown in Table 2. But the biggest disadvantage of this medium is that some of its ingredients are toxic.
Sealing material
Generally speaking, all anti-combustion media will seriously affect the performance of the sealing material, so when choosing the sealing material, we should be more cautious than choosing the sealing material in mineral oil.
We have extensive experience in this area and have done extensive and in-depth research on the compatibility of sealing materials with this medium. The results of the study and the recommend sealing materials are shown in Table 3.
| Medium Type | Operating Temperature | Applicable Materials | Others Optional |
| HFA-E | +5 ~ +55（60） | Nitrile rubber\Hydrogenated nitrile rubber\Special fluoro rubber | Special polyurethane (such as high temperature hydrolysis resistant polyurethane, self-lubricating polyurethane) |
| HFA-S | +5 ~ +60 | Must be tested | Special polyurethane (such as high temperature hydrolysis resistant polyurethane, self-lubricating polyurethane) |
| HFB | +5 ~ +60 | Nitrile rubber\Hydrogenated nitrile rubber\Special fluoro rubber | Special polyurethane |
| HFC | -20 ~ +60 | Nitrile rubber\High temperature resistant nitrile rubber\Synthetic rubber\Silicone rubber | Special polyurethane and special synthetic fluoro rubber |
| HFD-R | >+100 | Fluoro rubber\Synthetic rubber\Silicone rubber | |
| HFD-S | >+100 | Fluoro rubber\Silicone rubber | |
| HFD-T | >+100 | Fluoro rubber\Silicone rubber | |
| HFD-U | Silicone oil, >+100 | Fluoro rubber | Special polyurethane, maximum operating temperature 100℃ |
| Synthetic ester, +80 | Fluoro rubber | Special polyurethane (such as high temperature hydrolysis resistant polyurethane, self-lubricating polyurethane) |
Application Case
1. Hydraulic Seal Selection of Rolling Mill Hydraulic Pressure Cylinder (AGC)
Hydraulic pressure device (AGC Automatic Gauge Control) is a key component of hot rolling and cold rolling equipment, in which the cylinder is the actuator of the device, which belongs to the large diameter short stroke servo cylinder, its reliability and friction performance have high requirements. The oil cylinder is in high-frequency vibration and adjustment condition during normal operation. In order to achieve high frequency response and control accuracy, the seal is required to have low and constant friction, stable movement at low speed, and no low-speed crawling phenomenon. The material of the sealing element and the dust ring is generally filled with polytetrafluoroethylene (PTFE). The PTFE material has the lowest friction coefficient, and its starting friction coefficient is relatively close to the sliding friction coefficient, so there will be no low-speed crawling phenomenon, and it also has High wear resistance and anti-crevice extrusion ability.
2. Seal for cold rolling continuous annealing machine
The heat treatment method of electric heating and then cooling the thin steel plate is used to improve the physical properties of the steel plate on the cold-rolled steel plate production line of the steel plant. The temperature of heat treatment is relatively high, and the thin steel plate is transferred forward by winding on the rotating working roller. Since the heated steel plate is directly wound on the roller, the temperature of the roller is relatively high, and the supporting bearings at both ends of the roller also Keep a high temperature for a long time. Therefore, the bearing seal in this part requires high temperature resistance, low friction resistance and long life.
We developed TR19S seal, the outer frame is made of PEEK material, and the sealing ring can be made of PTFE, which obviously prolongs the maintenance cycle of the equipment.
3. Rolling mill work roll and support roll bearing seal
Roller bearing is an important part of the rolling mill. The quality and service life of the roller bearing are directly related to the product quality, production efficiency and production cost of the rolling mill. Therefore, the maintenance of the roller bearing is particularly important. During rolling, the roll is cooled with water, emulsion, etc., and the oxide skin can easily fall into the bearing. Therefore, the seal of the bearing put forward higher requirements.
Free inquiry
