Galvanized steel pipes are divided into cold galvanized steel pipes and hot-dip galvanized steel pipes. Cold galvanized steel pipes have been banned. In the 1960s and 1970s, developed countries in the world began to develop new types of pipes and gradually banned galvanized pipes. Four ministries and commissions including the Ministry of Construction of China have also issued a document stating that galvanized pipes are prohibited from being used as water supply pipes since 2000.
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Designed in 1835, the gas regulator's concept is easy, and its impact has been long-lasting. There are various types of regulators, but their function is the same: to use a valve system to control natural gas or propane pressure or other gas flow. Common appliances that use regulators include gas stoves, propane grills, or oxy-fuel bottles for welding.
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A T shirt, or tee shirt, is a style of fabric shirt named after the T shape of its body and sleeves. Traditionally, it has short sleeves and a round neckline, known as a crew neck, which lacks a collar. T-shirts are generally made of a stretchy, light, and inexpensive fabric and are easy to clean. The T-shirt evolved from undergarments used in the 19th century and, in the mid-20th century, transitioned from undergarment to general-use casual clothing.
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According to the openness of the slewing drive transmission mechanism, the slewing drive can be divided into an open housing slewing drive and a closed slewing drive. Usually, the open structure is mostly used in applications where the environment is too harsh and the maintenance and maintenance cycle is short.
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Pillow, a sleep tool. It is generally believed that pillows are the stuffing that people use to sleep comfortably. According to modern medical research, the spine of the human body is a straight line when viewed from the front, but a curve with four physiological curves when viewed from the side. In order to protect the normal physiological curvature of the neck and maintain normal physiological activities during sleep, pillows must be used when sleeping.
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