What is tube to tubesheet welding?

What is tube to tubesheet welding?

Tube to tubesheet welding heads – A closed chamber welding head allows the execution of fusion welding without the addition of filler wire.

What are the types of tube to tubesheet joint available?

There are four types of tube-to-tubesheet joints:

• Roll or expand only (without grooves) – strength is poor.
• Roll or expand only (with grooves) – strength is limited (can be improved by explosive expansion)
• Roll or Expand and Seal Welded (with grooves)
• Strength Weld (no grooves required)

What is the minimum leak path in tube to tubesheet welding?

The minimum leak path of each weld shall be not less than the nominal thickness of the tube. The weld leg shall also be measured and shall be minimum 1.4 times the nominal thickness of the tube.

What is minimum leak path?

Definition – Minimum Leak Path for the strength weld joint is the minimum distance required by a fluid from root side of the weld to get leaked from face side i.e. Tubesheet side. Generally, requirement of MLP is same as the tube thickness.

What is tube sheet?

A tube sheet is a plate which is used to support the tubes in a shell-and-tube heat exchanger. The tubes are aligned in a parallel way, and supported and held in place by tube sheets. The tube sheet is a circular plate which is perforated so that the tubes can fit through the openings.

What is tube expansion in heat exchanger?

Tube Expanding is the process of reducing a tube wall by compressing the outer diameter (OD) of the tube against a fixed container, such as rolling into tube sheets, drums, ferrules, or flanges. To assure a proper tube joint, the tube wall must be reduced by a predetermined percentage.

Which type of exchanger can be used for thermal expansion of tubes?

In the “U” -tube exchanger, the shape of the tubes takes care of differential expansion. As the name implies, the tubes have a “hairpin” shape, with both ends of the tube fastened to one tubesheet. This “U” bend design allows each tube to expand and contract independently.

What is tube pattern?

Tube patterns on the tubesheet help in heat transfer process by allowing the fluid pass through each tube as per the patterns drilled on the tube sheet. Tube patterns and pitch is the most important and complex part of the tubesheet design which decides the heat transfer in the heat exchanger.

What is a tube bundle?

A tube bundle is a set of tubes in a shell-and-tube heat exchanger. A set of tubes is called the tube bundle and can be made up of several types of tubes. In a shell-and tube-exchanger the tube bundle is enclosed in a cylindrical shell, through which the second fluid flows.

How do you calculate expansion of a tube?

By subtracting “E” from the rolled diameter you determine the actual amount of expansion (tube wall reduction) on the inside diameter of your tube. This can be converted to a % of wall reduction by dividing the actual wall thickness (“B minus D”) .

What is expander machine?

“Expander” processing. Tube Expanders are rolling tube type expansion tools used for fixing and molding tubes to tube sheets in the manufacturing processes of heat exchangers such as boilers and condensers.

What is Beu heat exchanger?

The BEU heat exchangers are shell and tube exchangers with tube bundle consisting of specially “U” shaped tubes fixed by mechanical rolling to only one tube sheet. This type of exchanger is designed and built with removable shell and tube to allow easy maintenance.

How do you calculate tube expansion percentage?

What is Tubesheet?

How many tubes are in a condenser?

The condenser, usually located beneath the low-pressure steam turbine exhaust, may contain 50,000 or more tubes. A condenser overhaul requires removal and replacement of each tube, a labor-intensive job. Courtesy: Conco Systems Inc.

What is tube expansion?

Why is tube expansion done?

Tube Expansion is the process of reducing a tube wall by displacing the outside diameter of the tube against a fixed container such as rolling tubes into tube sheets. To assure a proper tube joint to the tubesheet, the tube wall must be reduced by a predetermined percentage.