Internally threaded finned tubes are also called dry steam pipes, internally ribbed pipes or internally finned pipes. In central air conditioners, it is mainly used in dry evaporators. During heat exchange, the water outside the tube is cooled by the refrigerant that evaporates and expands in the tube; it is also used in household and commercial air conditioner heat exchangers or in high heat pipes.

Internally threaded fin tube

The internal surface area per unit length of the internally threaded pipe is 1.5-2 times that of ordinary smooth copper pipes, and its heat transfer coefficient is 1.5-2.4 times that of smooth copper pipes of the same specification, while the flow resistance of the carrier only increases by 3-5%, which can It saves energy by 20-35% and reduces the weight of the refrigeration air conditioner by 10-25%.
To facilitate installation, internally threaded pipe is usually delivered in straight strips. The size range of internally threaded pipes is shown in the chart below. The specific tooth shape parameters and pipe end requirements can be negotiated and customized according to user requirements.

Please see the chart below for specifications and parameters of internally threaded pipes

Implementation standards: YS/T440, GB/T19447 or equivalent to ASTM B359, ASME SB 359
Material: red copper T2/TP2, iron-nickel copper BFe10-1-1, complex brass HSn70-1, HA177-2, etc.
Status: Wing fragment Y2 or M
Specification range:
Optical end outer diameter Do: Φ7~Φ16mm
Optical end thickness To: 0.40-1.50mm
Bottom wall thickness Tw: 0.25-1.10mm
Tooth height Rh: ≤0.15-3mm
Helix angle β: 0°~ 28°
Total length L: ≤8m
Packaging: wooden box packaging