1. After heat treatment, the metallographic structure of high pressure hot drawn tee pipe is the same as that of raw material;Surface hardness;Alloy steel is HB125~197.

2. No cracks are allowed on the surface of high pressure hot drawn tee pipe fittings;The surface is smooth, scar, wrinkle and other defect depth is not more than 1.6mm;The depth of surface scales and heavy skin is not more than 0.4mm.

3. Geometrical dimensions and deviations of high pressure hot drawn tee pipe fittings, such as inner and outer diameters of ports, inner and outer bevels, deviation of end face slope and height of branch pipes, should meet the requirements of drawings;The butt wall thickness of the product port shall not be less than the small value allowed by the nominal wall thickness of the connecting pipe, and the wall thickness of the other parts shall not be less than 90% of the design wall thickness, and the small part shall not be less than 87.5%.The ovality outside the port shall not be greater than 6% of the nominal outer diameter;When the port wall thickness is greater than 1.15 times the pipe wall thickness, the inner groove shall be remachined according to the standard.

4. The through-flow area of high-pressure hot-drawn tee fittings should not be less than 90% of the main through-flow area.