Views: 12 Author: Site Editor Publish Time: 2021-02-18 Origin: Site
Because foaming relies on heat, if there is no heat, the foaming agent in the system cannot evaporate and foam plastic cannot be formed. The heat comes from two aspects, one is the heat produced by the chemical reaction, and the other is the heat provided by the environment. The heat of chemical reaction is a fixed value, without the influence of external factors, but the heat provided by the environment changes with the change of the ambient temperature.
When the ambient temperature is high, the environment can provide heat to the reaction system, which can increase the reaction speed and shorten the reaction time. It is manifested as the foam is fully foamed, and the density of the foam surface and core is close. When the ambient temperature is low, part of the reaction heat is dissipated to the environment The heat loss, on the one hand, causes the foam maturation period to be prolonged and increases the foam molding shrinkage rate; tests show that the same foam material, the foaming volume at an ambient temperature of 15 ℃ is 25% smaller than that at 25 ℃. On the other hand, a hard skin that is not fully foamed or even hugged will be formed on the surface of the foam, which increases the amount of foam infusion and increases the cost of foam production.
At present, the most common type of cement foaming machine on the market is the third-generation cement foaming machine (the first and second generations have been basically eliminated). Its structure can be roughly divided into several parts: feeding system, mixing system, foaming system, and conveying system. Then we use this to make a simple analysis of various cement foaming machines:
1. Feeding system
At present, the main feeding devices of cement foaming machines in China are screw propellers and belt conveyors. Screw propellers used to have small size, low cost, good sealing performance, less environmental staining, and beautiful appearance, but after several years of practice However, several shortcomings were discovered, 1. High failure rate and frequent crashes; 2. Small feed volume, which could not meet the construction needs; 3. Short life span and troublesome maintenance, gradually eliminated by consumers. The belt conveyor with good sealing performance has been recognized by consumers because of its large feed volume, low failure rate and simple maintenance.
2. Mixing device
When other conditions are the same, the strength of foamed concrete with uniform mixing and non-uniform mixing can differ by 3%-10%, and sometimes by 20%. The third-generation cement foaming machines all use horizontal horizontal shafts, similar to horizontal mortar-type concrete mixers, mixing with high-speed blades installed on the horizontal shaft to achieve uniform mixing of cement and water. The main components of the mixing system are the barrel, the horizontal shaft, the mixing blade and the motor.
1. The twisted blades should be designed reasonably, and it is best to avoid uneven materials accumulated in dead corners during mixing. All parts of the twisted leaves should be stirred, so the best gap between the twisted leaves and the barrel is 10-20mm. Buyers can use tools to measure the distance between the hinge leaf and the four walls for inspection.
2, The connection between the horizontal shaft and the hinge blades is best to use mechanical connection. If the horizontal shaft and the hinge blades are fixed by welding, the horizontal shaft will inevitably be deformed and bent when heated, and cannot be parallel to the axis. When the machine is running, it must be twisted. It is also the main reason that the horizontal shaft seal is prone to material leakage. The mechanical connection will not cause deformation of the horizontal axis during installation and is convenient for disassembly.
Yesterday, the 2024 Hightop Group Annual Meeting Ceremony with the theme of “Change and Breakthrough, New Journey” came to a successful end in Wanda Jiahua Hotel. All the staff of Hightop Group gathered together to review the struggle of the past year and look forward to the new journey full of hope
All family members.According to the provisions of the national statutory holidays, and combined with the actual situation of the company, the Spring Festival holiday in 2025 is arranged as follows.First, January 25th afternoon (Saturday) to February 4th (Tuesday) holiday, a total of 10.5 days, Janua
Recently, Shandong Hightop Group ushered in a moment of great significance -- the groundbreaking ceremony of Hightop Group's headquarter base project was held in grand style. The launch of this project is not only an important milestone in the development course of Hightop Group, but also a powerful
聚氨酯发泡机 仓库室内保温防冷凝水 如何使用聚氨酯发泡机来为仓库进行室内保温,并且防止冷凝水的出现呢? 我们需要了解到仓库的保温和防冷凝水两个需求。 仓库在冬季往往面临着室内外温差大的问题,导致室内空气中的水蒸气凝结成冷凝水,聚氨酯发泡机能够有效的保温和防止水蒸气的凝结。 其次,在了解具体的应用方案前,我们还需要知道如何选择合适的聚氨酯发泡机。选择时应该考虑到机器的效率、稳定性、易用性和维护成本等因素。 最后,为了确保仓库的保温效果和防冷凝水效果,我们需要对聚氨酯发泡机进行合理的使用和维护。在使用过程中,要遵循操作规程,避免违规操作,并且定期对设备进行检查和维护。 通过以上方法
On January 11, the CNMC-E3 polyurethane spraying machine was loaded in the industrial park and will be exported to Spain. CNMC-E3 polyurethane spraying machine is widely used in industrial maintenance, tunnels, subways, roadbed waterproofing, foam film and television props production, pipeline anti-
Hey,friends!Can you believe it? 2025 is just around the corner! I wanted to reach out and send you my happiest wishes for the upcoming year.Our time working together this past year has been so much fun, and we've overcome challenges and celebrated victories side by side. I'm really looking forward t
Recently, the Department of Commerce of Shandong Province released the list of “Key Cross-border E-commerce Entities to be Cultivated in Shandong Province in 2024”, and Shandong Hightop Group has been successfully selected for the list due to its outstanding performance in cross-border e-commerce an
Solar hot water pipe casing insulation is a sandwich structure composite insulation pipe, which is composed of an inner PPR hot water pipe, an outer PVC pipe and a central polyurethane foam insulation layer. Polyurethane insulation pipe is a kind of insulation pipe that transports hot water from the
Polyurethane elastomers are typical multi-block copolymers, where the molecular chain consists of flexible chain segments with a glass transition temperature below room temperature and rigid chain segments with a glass transition temperature above room temperature. The oligomer polyol constitutes th
Cold storage spray polyurethane focuses on the overall seamless condition after spray foaming. Polyurethane has good density, insulation and cold resistance. It is basically a closed cell structure. It not only has excellent thermal insulation properties, but also has good resistance to freezing and