U Bend Tubes
U Bend Tubes
Pantani Divisione Tubi core business is U bend tubes for heat exchangers applied mostly in Oil & Gas plants, Chemical & Petrochemical plants, Refineries, Power plants, Renewable energy plants.
Materials
- Copper alloys
- Carbon steel
- Low alloy steel
- Stainless steel (austenitic, ferritic, super austenitic)
- Duplex alloys (UNS S32750, UNS S32760)
- Titanium (Gr.2, Gr.12)
- Monel alloys
- Nickel alloys
U bend dimension capability
| Tube OD | Tube thickness | Bending Radius | U tube straight “leg” length | Straight tube before U bending |
| Min. 12,7mm / Max. 31,75mm | Min. 0,70mm / Max. 4,19mm | Min. 1,5 x OD / Max. 1250mm | Max. 12500mm | Max. 27000mm |
Dimensional controls on U bend tube
– Ovalization of straight and bending portion (A-B-C-D-E-F-G)
– Thinning of straight and bending portion (A-B-C-D-E-F-G)
– Leg spacing length (I.A.1 + I.A.2)
– U bend tube length (leg + radius + (0,5 x OD))
– Difference between legs length
– Straightness of legs
– Deviation from bend plane
– Twist of bending portion
– Squareness and cleanliness of tube ends
– Complete visual check
Tollerance
Standards usually required to establish U bend tube tolerances:
– ASTM A556/556M
– ASTM B395 / B395M
– ASTM A688/688M
– ASTM A803/803M
– TEMA Section 5 § RCB 2.31
– DIN 28179
Post bending heat tratment by electric resistance (Joule Effect)
After U bend (cold forming), heat treatment of bending portion may be required. Pantani Divisione Tubi is equipped with 2 heat treatment machines and 1 nitrogen generating machine (to protect stainless steel tube surface during annealing). Temperature is controlled through the entire heat treated area by fixed and portable infrared pyrometers.
Post bending NDT control
– Hydrostatic Test
– Air Underwater Test
– Pulsating Test
– Dye Penetrant Test
– Magnetoscopic test
Packing
Any type of packing is available according to customer need to worldwide destinations.
