Views: 0 Author: Site Editor Publish Time: 2024-11-08 Origin: Site
In order to select the shrinkage rate of large cast polyurethane elastomer products more accurately, the influences of process conditions, environmental factors and product structure on the shrinkage rate were systematically investigated, and the change curves of shrinkage rate with time were measured. The reasons were analyzed. The results show that the product structure has the greatest influence on the shrinkage rate, the process conditions also have a greater influence on the change of shrinkage rate, while the fluctuation of environmental conditions is the reason for the late fluctuation of shrinkage rate. The selection of shrinkage rate is one of the key factors to determine the success of mold design. Especially for large (part size in 1 o00 m / n or more) polyurethane elastomer products, because of its shrinkage rate is large (generally in the 1.5% or so), if the shrinkage rate is not selected properly, light is to increase the amount of mold repair, extend the manufacturing time of the mold, increase the cost of the mold; heavy is due to the size of the mold is too large and scrapped. Therefore, it is important to analyze the reasons for the shrinkage of polyurethane elastomers and study the qualitative relationship between shrinkage and process conditions for the design of cast polyurethane elastomer molds. In this paper, through a large number of process experiments, a more comprehensive study of process conditions, structural factors and environmental conditions on the impact of shrinkage.
The changing law of shrinkage of polyurethane elastomer is:
1) increase with the increase of mold temperature;.
2)with the prolongation of the aging time is jagged change; and
3) with the increase of the ambient temperature and reduce.
4)Fluctuation with the increase of ambient humidity; and
5)Different mold structures have different degrees of hindrance to shrinkage, with the longitudinal direction being the smallest and the transverse direction being the largest; and
6)Shrinkage increases with the increase of flow path length before a certain length, and decreases with the increase of flow length after exceeding a certain length.
It can be seen that the process conditions have a certain impact on the shrinkage rate, and the most significant effect of temperature; the structure of the product itself has a greater impact on the shrinkage rate, polyurethane elasticity of the system is mainly caused by the different flow paths; environmental factors are the later impact factors, their changes are the main factors of the fluctuations in shrinkage rate.
With the help of cold storage polyurethane foaming machines, we have the opportunity to send out high-quality foam products. After market testing, the polyurethane foaming machine has many advantages, easy to use, and the foaming efficiency can also be improved. Learn more, use it in the right envir
With its own characteristics, polyurethane spraying machines show significant advantages in many industries, which are carried out from the dimensions of construction, performance, and application: First, the advantages of construction adaptabilityFull coverage of complex substrates: whether it is
Cesspool treatment works, as the name suggests, is a sewage treatment tank. Most of the sewage ponds are reinforced concrete structures. The main plant wastewater treatment pool is alternating acid and alkali, corrosive chemical sewage, pH value is often between 3-4. If the pool is not protected and
I believe that many large-scale enterprise plant owners know, color steel tile room use time is long time to regularly renovate its maintenance. But not insiders may not know is color steel tile room renovation really deep water, different price different specification brand polyurethane spraying eq
Dual-speed sprayer is a breakthrough equipment in the modern spraying field, which realizes the double improvement of spraying efficiency and precision through the innovative dual-mode power system. Its core principle is based on intelligent speed switching and pressure control, which is widely used
In many fields such as industrial protection and building waterproofing, polyurea materials have been widely used for their excellent performance advantages. In order to give full play to the characteristics of polyurea materials, a high-performance spraying equipment is crucial, and the CNMC-A25 po
On March 31, 2025, Hightop Group's housewarming celebration was held in the new headquarters office building at 66 Xinyuan Road, Jining. All Hightop employees, partners and other industry leaders gathered together to witness important milestones in the development of the enterprise and open a new ch
In the era of the booming development of cross-border e-commerce, a piece of good news has added a beautiful color to the commercial map of Shandong Province. Recently, the Shandong Provincial Department of Commerce officially announced the "Shandong Provincial Department of Commerce on the identifi
construction field Thermal insulation: can be used for building roofs, walls, floors and other parts of the thermal insulation treatment, such as in the new residential and commercial buildings of the external wall spraying inorganic fiber wool, can effectively prevent the heat transfer, reduce ener
Recently, Jining Economic Development Zone grandly held the second high-quality development and high-level opening conference. The conference aims to fully implement the spirit of the central and provincial and municipal private enterprises Symposium, summarize the effectiveness of high-quality deve