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I. General components
1. Screw
(1) Definition:
The screw is a standard thread fastener, usually including a head, a shank, thread, a point and a tip.
(2) Requirements:
a. The size, shape and specification of the head, shank, thread, point and tip should meet the requirements of the drawing.
b. The surface of the screw should be smooth and without burr and any tailing thread.
c. The surface of the screw should be free from rust and oil stain.
2. Nut
(1) Definition:
The nut is a standard thread fastener, generally including a top, a bottom and a thread.
(2) Requirements:
a. The size, shape and specification of the top, bottom and thread should meet the requirements of the drawing.
b. The surface of the nut should be smooth and without burr and any tailing thread.
c. The surface of the nut should be free from rust and oil stain.
3. Washer
(1) Definition:
A washer is a flat product with a hole, mostly used in combination with screws, nuts and other fasteners to increase the relationship between the parts and fix them.
(2) Requirements:
a. The size, shape and specification of the washer should meet the requirements of the drawing.
b. The surface of the washer should be smooth and without burr.
c. The surface of the washer should be free from rust and oil stain.
4. Gasket
(1) Definition
A gasket is a product made of various materials, mostly used to prevent leakage between two parts when they are connected.
(2) Requirements:
a. The size, shape and specification of the gasket should meet the requirements of the drawing.
b. The surface of the gasket should be smooth and without burr.
c. The surface of the gasket should be free from rust and oil stain.
d. The gasket should have good performance in water tightness, air tightness, heat insulation and insulation.
5. O-Ring
(1) Definition
O-ring is a circular sealing component, with a rectangular cross-section, mostly used for sealing, dustproof and decoration.
(2) Requirements
a. The size, shape and specification of the O-ring should meet the requirements of the drawing.
b. The surface of the O-ring should be smooth and without burr.
c. The surface of the O-ring should be free from rust and oil stain.
d. The O-ring should have good performance in water tightness, air tightness, heat insulation and insulation.
