Figure 1. The construction of the NUT-SEAL system protector assembly: A. standard grease fitting; B. elastomer membrane; C. HDPE barrel; D.LDPE hex nut cover; E. hex area for removal.

Assembly

The NUT-SEAL system protector assembly is in two parts: a barrel and a hex nut cover. The barrel (C) is made from hard, high-density polyethylene (HDPE). This material can withstand heavy shocks while effectively protecting the bolt threads. The bottom hex nut cover (D) is made of softer, low-density polyethylene (LDPE) that protects and covers the nut. The hex on the barrel (E) is for removal of the protector, if needed for bolt removal, after long periods of use. The standard grease fitting (A) is for injection of the anticorrosion grease into the protector.

The protector is supplied with either a long or short barrel. The long barrel is used in conjunction with tensioning devices. Tensioning requires a thread height approximately two times the height of the nut or twelve exposed threads. The short barrel is used where tensioning is not required and allows for six exposed threads. Grease fittings are installed either on the top or the sides of the barrel. The system can be supplied with special, non-standard, thread configurations, and can be properly tapped with special thread types.

The elastomer membrane (B) serves three functions. First, it indicates that no empty space remains in the protector and that the threads are completely covered with grease. Second, it maintains a positive pressure in the protector preventing the infiltration of corrosive agents. Third, it provides a visual indication that the pressure remains in the protector allowing easy inspection and injection of additional grease, if indicated.