Today, Chenyangpump, a Chinese asphalt pump manufacturer, will introduce the sealing principle of asphalt pumps. The article will introduce in detail the common materials of asphalt pump mechanical seals and the technical essentials of asphalt pump mechanical seal installation and use.
1. Asphalt pump mechanical seal
The mechanical seal of the asphalt pump is a shaft seal device that relies on a pair or several pairs of end faces that are perpendicular to the shaft to slide relatively under the action of fluid pressure and the elastic force (or magnetic force) of the compensation mechanism and is matched with an auxiliary seal to prevent leakage.
2. Types and uses of asphalt pump sealing materials
The sealing material should meet the requirements of the sealing function. Due to the different media to be sealed and the different working conditions of the equipment, different adaptability of the asphalt pump sealing material is required. The requirements for sealing materials are generally:
1) The material has good compactness to ensure the tightness of the asphalt pump and ensure that the medium is not easily leaked;
2) Appropriate mechanical strength and hardness to improve the overall performance of the asphalt pump;
3) Good compressibility and resilience, small permanent deformation, and prolonged service life of asphalt pump sealing materials;
4) No softening or decomposition at high temperatures, no hardening or brittle cracking at low temperatures;
5) Good corrosion resistance, ensuring that the asphalt pump can work for a long time in acid, alkali, oil, and other media, its volume and hardness change is small, and it does not adhere to the metal surface;
6) Small friction coefficient and good wear resistance;
7) It has the flexibility to combine with the sealing surface;
8) Good aging resistance and durability;
9) It is easy to manufacture, cheap, and easy to obtain materials.
Rubber is the most commonly used sealing material. In addition to rubber, graphite, PTFE and various sealants are suitable for asphalt pump sealing materials.
3. Technical essentials of installation and use of the mechanical seal of asphalt pump
1) The radial runout of the asphalt pump shaft should be less than or equal to 0.04 mm, and the axial movement should not be greater than 0.1 mm;
2) The sealing part of the equipment should be kept clean during installation, the sealing parts should be cleaned, and the sealing end face of the asphalt pump should be intact to prevent impurities and dust from being brought into the sealing part;
3) During the installation process, it is strictly forbidden to hit or knock, so as to avoid friction and damage to the mechanical seal of the asphalt pump and the seal failure;
4) During installation, a layer of clean mechanical oil should be applied to the surface of the asphalt pump in contact with the seal, so that it can be installed smoothly;
5) When installing the static ring gland, the tightening screws must be evenly stressed to ensure the vertical requirements of the end face of the static ring of the asphalt pump and the axis line;
6) After installation, push the moving ring by hand so that the asphalt pump moving ring can move flexibly on the shaft and has a certain elasticity;
7) After installation, turn the shaft by hand, and the shaft should not feel heavy;
8) The asphalt pump must be filled with the medium before the operation to prevent the seal from being ineffective due to dry friction;
9) For easy-to-crystallize and granular media when the temperature of the medium is less than 80oC, corresponding measures of flushing, filtration and cooling should be taken. For various auxiliary devices, please refer to the relevant standards for mechanical seals of asphalt pumps.
10) During installation, a layer of clean mechanical oil should be applied to the surface in contact with the asphalt pump seal, and special attention should be paid to the selection of mechanical oil. For different auxiliary seal materials, avoid O-ring expansion or accelerated aging caused by oil invasion. The seal failed prematurely.
I hope that the content of the asphalt pump mechanical seal introduced by the Chenyangpump asphalt pump manufacturer above will be helpful to you. More asphalt pump-related information will continue to be updated. If you want to get more asphalt-related information, please refer to the following:
