三区一级_97欧美一乱一性一交一视频_精品国产一区二区三区久久久樱花_久久久99国产精品免费_国产精品午夜福利_国产大屁股喷水视频在线观看

CLOSE

Talking about the construction and identification of PVC pipes.

Jan. 21, 2021

PVC is polyvinyl chloride, and other components are added to the PVC pipe to enhance its heat resistance, toughness, ductility, etc. The top layer of this surface film is lacquer, the main component in the middle is polyvinyl chloride, and the bottom layer is back-coated adhesive. It is currently the most popular, popular and widely used synthetic material. Its global usage ranks second among various synthetic materials.

PVC pipe is made of polyvinyl chloride resin, stabilizer, lubricant, etc., and then extruded by hot pressing. It is the first plastic pipe to be developed and applied. PVC-U pipe has strong corrosion resistance, easy bonding, low price, and hard texture. However, due to the exudation of PVC-U monomer and additives, it is only suitable for water supply systems whose output temperature does not exceed 45°. Plastic pipes are used to output drinking water, waste water, chemicals, heating fluid and cooling fluid, food, ultra-pure liquid, mud, gas, compressed air and vacuum system applications.

pvc pipe

Identification method of PVC pipe:

First of all, the surface finish and whiteness of the PVC pipe; then take the sample to test, the ones that are easy to break are usually high-calcium products, of course, they must meet the requirements, and the price is right; then take the sample to step on the edge of the pipe, See if it can be cracked, or the elongation at break after cracking; whether it is good in weather resistance. The most direct way is to store the PVC pipe in a high-temperature and high-gloss place for a few days, and then look at its surface change rate, but this is a waste of time.

Application of PVC pipes:

The essence of PVC pipe is a kind of vacuum blister film, which is used for the surface packaging of various panels, so it is also called decorative film and adhesive film, which is widely used in building materials, packaging, medicine and many other industries.

返回頂部
CLOSE
主站蜘蛛池模板: 麻豆果冻国产剧情AV在线播放 | 精品在线视频一区二区三区 | 高清乱码免费网站 | 欧美日韩久久精品 | 无码人妻视频一区二区三区 | 国语自产拍在线观看对白 | 中文成人无码精品久久久不卡 | 日韩免费高清大片在线 | 字幕日韩视频一区二区 | 国产美女www | 精品一区二区三区蜜桃 | 欧美乱大交xxxxx春色视频 | 亚洲精品中文字幕av | 特级毛片免费 | 亚洲中文久久精品无码浏不卡 | 日韩精品一二三区 | 一区高清 | 久久精品爱看无码免费视频 | 国产一区二区三区不卡在线 | 亚洲乱亚洲乱妇91p丰满 | 国产精品一级二级在线观看 | 人妻聚色窝窝人体WWW一区 | 国产a级理论片无码老男人 午夜视频在线观看一区二区 | av性网站| 午夜影院在线观看版 | melody高清在线观看 | 日本色偷偷 | 在线精品婷婷日韩 | 日韩精品一区二区大桥未久 | 亚洲欧美成人一区二区 | 亚洲中文字幕无码爆乳AV久久 | japan白嫩丰满少妇 | 欧美一级一级一级 | 国产精品久久久久永久免费 | 亚洲欧美日韩中文字幕在线一区 | 日韩av一区二区在线观看 | 国产成人精品日本亚洲网站 | 四虎影视久久久免费 | 成人免费网站视频ww破解版 | 国产精欧美一区二区三区久久久 | 毛片TV网站无套内射TV网站 |