What is a cross？

Four-way for pipe fittings, pipe connectors. Also called pipe fittings or four-way fittings, four-way joints, used in the main pipe to branch pipe.

The four-way has equal diameter and reducer points, equal diameter four-way takeover end are the same size; reducer four-way takeover size of the main pipe is the same, and the takeover size of the branch pipe is smaller than the main pipe takeover size. The cross is a kind of pipe fittings used in the branch of pipeline.

Hydraulic Expansion
Hydraulic expansion of a cross is a molding process that expands a branch pipe through the axial compensation of metal materials.

Welding cross
The process is to use a special hydraulic press with a diameter equal to the billet injected with liquid, through the hydraulic press of the two horizontal side cylinders synchronized with the movement of the billet extrusion billet, billet by the extrusion of the volume of the billet becomes smaller, the billet with the billet of liquid volume becomes smaller and the pressure rises, when reaching the four-pipe expansion of the required pressure, the metal material in the side cylinders and billet under the double action of the pressure of the liquid flow along the inner cavity of the mold and expanding branch pipe. Hydraulic expansion process of the four-way can be a molding, high production efficiency; four-way of the main pipe and shoulder wall thickness have increased. Due to the hydraulic expansion process of seamless cross the equipment required for the larger tonnage, is currently mainly used for less than DN400 standard wall thickness of the manufacturing of cross. The applicable forming materials are mild steel, low alloy steel, stainless steel with relatively low tendency to cold work hardening, including some non-ferrous materials such as copper, aluminum, titanium and so on.

Hot press forming
Four-way hot compression molding is larger than the diameter of the four-way billet, flattened to about the size of the diameter of the four-way, in the stretching of the branch part of a hole; billet heated, put into the forming mold, and in the billet installed in the stretching of the branch of the die; in the role of pressure billet is radial compression, in the radial compression of the process of the metal to the branch of the direction of the flow and in the die under the stretching of the formation of the branch. The whole process is formed by the radial compression of the billet and the stretching process of the branch pipe part. Unlike the hydraulic expansion four-way, the metal of the hot pressed four-way branch pipe is compensated by the radial movement of the billet, so it is also known as the radial compensation process.

The tonnage of equipment required for material forming is reduced due to the use of heated and then pressed crosses. The adaptability of the hot pressing four-way to the material is wider, suitable for low carbon steel, alloy steel, stainless steel materials; especially large diameter and pipe wall thickness of the four-way, usually used in this molding process.

1. Divided by material carbon steel, cast steel, alloy steel, stainless steel, copper, aluminum alloy, plastic, argon-chrome asphalt, pvc and so on.

2. The production method can be divided into the top system, pressing, forging, casting and so on.

3 to the manufacturing standard can be divided into national standard, electric standard, water standard, American standard, German standard, Japanese standard, Russian standard, etc., specific as follows: GB/T12459, GB/T13401, ASME