The most common type of nut is the hex nut. This has a hexagonal outer shape for the faces of tools to apply torque when fastening. To provide a secure fastening, this type of nut typically relies on torque being applied to generate an axial force. This axial force causes sufficient friction at the threads so as to prevent the nut from unscrewing. The force may act between the bolt head and the nut, causing compression of the parts being fastened. Alternatively, it may act between a pair of adjacent nuts, allowing parts to be fastened more loosely.http://www.yuchaobolt.com/bolt/hex-bolt/

Another indispensible equipment is steel pipe printing marking machine. Companies that produce metal pipes, regardless of whether they are involved in construction, aerospace, electronics, etc., code these materials to enable traceability, display important production data, and prevent counterfeiting. These codes generally take the form of numeric lot numbers or machine-scannable bar codes.http://www.westwu-machine.com/....pipe-spray-painting-

The way a ball valve functions makes it easy to see if the valve is open or shut. The handle that operators use to adjust where the sphere is aligned with the flow when the valve is open, and it is perpendicular when the valve is closed. And the ball valve can be devided into many different types for different functions, such as floating ball valve, trunnion mounted ball valve, top entry ball valve, dbb ball valve, subsea ball valve, etc.

http://www.tfcvalve.com/butterfly-valve/

1. Draw your design with the glue pen
On a blank sheet of watercolor paper, doodle or draw your resist design using the glue pen. This glue pen has a clear glue for ink and the design you draw won’t be easily visible unless you tilt your paper to the light. Let this glue design dry for a few minutes, it shouldn’t take longer than 5 minutes.

http://www.subbuteo.com.cn/mai....n-products/lithium-b

Since the introduction of aspirin in 1899, and more particularly since the advent of antibiotic "wonder drugs" in the 1940s, society has come to rely on the widespread availability of therapeutic drugs at reasonable prices. It was a tremendous challenge to bring penicillin to market and could not have been done without the simultaneous development of both product and process under the inspired leadership of Howard Florey over a 10 year period starting in the early 1930s, much has changed in drug development, but the timelines remain long, and the obstacles to success remain high.http://www.purestchem.com/phar....maceutical-intermedi