steel-valve
My blogs
| Location | 顺德, 广东, China |
|---|---|
| Introduction | Shunde, Guangdong, CN (http://steel-valve.blogspot.com/) A valve is a mechanism which changes the length of the tube, or body of a wind instrument; it allows you to play a wider range of notes. A piston valve features a that moves up and down in a casing; a rotary valve changes the air passage by means of a rotor activated by a lever. in the blog we will introduce many different types of valves to you. the basic valve types can be divided into two general groups: stop valves and check valves. |