Threaded Cross

Threaded Cross is a fully threaded pipe fitting in the shape of a cross, with internal threads on all four ports. It enables four-way connection of pipes through threaded engagement and is widely used in small and medium-sized, low-pressure, and frequently disassembled pipeline systems. It is a convenient connector for multi-channel diversion in water supply and drainage, fire protection, and instrument pipelines.

Structure and Manufacturing

The main body of the threaded four-way is a forged or cast "cross" shaped structure, and all four ports are machined with internal threads (commonly NPT, BSPT standards). The thread accuracy meets ANSI B1.20.1 specifications, with a tooth angle of 60 ° (NPT) or 55 ° (BSPT), ensuring tight engagement with external threaded fittings. The inner diameter of the port matches the outer diameter of the corresponding pipeline, and the diameters of the main and branch pipes can be the same (equal diameter four-way) or different (reducing four-way, such as DN50 × DN25). The materials are mostly carbon steel (A105) and stainless steel (316L), and forged products have denser materials, suitable for medium pressure scenarios; The cost of casting products is relatively low, and they need to undergo non-destructive testing to avoid porosity.

Connection and Performance

No welding is required during connection, and sealing is only achieved through threaded engagement with sealing materials (raw tape, thread sealant). The installation time is only one-third of that of welding a four-way joint. Capable of withstanding pressures ranging from Class 150 to Class 300 (1.6-5MPa), operating temperatures between -20 ℃ and 200 ℃, and suitable for non corrosive media such as water, compressed air, and light oil products.

Compared to socket welding tees, its core advantage is that the fully threaded design allows for the disassembly of any port, making it easy to clean the pipeline or replace components; No need for hot work, suitable for explosion-proof areas such as gas stations and chemical tank areas. But the thread is a stress concentration point, which is prone to leakage under high pressure or severe vibration, so it is not suitable for high pressure (>5MPa) or high temperature (>200 ℃) scenarios.

Applicable scenarios

Branch of building fire protection riser (connected to fire hydrant branch for easy maintenance and replacement);

Four way water distribution system for air conditioning (stainless steel material for rust prevention);

Sampling branch of chemical instrument pipeline (connecting multiple analytical instruments for easy disassembly and calibration).