Cone head: In the bolt ball grid in the thick pipe diameter pipe connected with the ball, in order to avoid head collision (a ball generally connected to eight tubes) and the head made of tapered, this to the pipe A tapered preform is called a cone.

Sleeve: A hexagonal sleeve designed to allow the bolts of a steel pipe head to be screwed tightly into a threaded hole of a ball when the pipe is connected to the ball.

The cone is a rotating thick-walled shell that receives the axial force from the tension of the bolt or the axial symmetry of the sleeve. Cone and bolt is the axis of symmetry of the rotating body, cone and bolt constraints are also axisymmetric.

Grid-type sleeves commonly known as no pattern nut, above a small hole, set to high-strength bolts, holes aligned high-strength bolts on the keyway, the top wire screwed in, so wrenching screw nuts (sleeve) Pieces inside the high-strength bolts also will rotate. With high strength, good corrosion resistance, good decorative beauty, low prices and so on.