Combination Beading Expanders

Why we Bead Tubes

The Powermaster Combination Beading Expanders are one of the most useful and time-saving tools available when tubes need to be beaded. The beading of tubes is to transfer high temperatures back into the tube sheet from the tube ends. If left unbeaded, the high temperatures could cause the tube ends to burn back and fracture. Beading the tube over so it is in contact with the sheet, allows the heat to disperse into the larger mass of metal.

Tool Description - Combination Beading Expanders

The combination beading expander consists of four tube rollers and one beading roller. A front guide roll assembly is determined by the wall thickness of the tube. The mandrel assembly includes the mandrel and the mandrel stop which is the adjustment for the beading aspect. If the mandrel stop is adjusted too far in then the bead will be off the tube sheet. The opposite adjustment will cause the bead to Gaul on the tube sheet.

Operation of the Combination Beading Expanders

The combination beading expander simultaneously expands and beads the tube end in a single operation. Therefore, operating as it does, the tool assures the creations of a joint. This then is both pressure tight and has a bead in intimate contact with the tube sheet. The tool achieves this objective by the natural feed force built into the expander to force the beading roller against the end of the tube while expansion is taking place. 

The ability of the tool to satisfactorily accomplish this depends upon the amount of tractive force available being of enough magnitude to enable feeding forces to be developed which will enable the beading roll to deform the end of the tube and press the bead tightly against the sheet. 

The tractive force is made a maximum by utilizing five expansion rolls in place of the three or four normally found in combination beading expander of this type and using coolant, which has the quality of minimum lubricity. If the beading roller expander is set so full expansion is accomplished before the bead has been formed, it will not be possible to complete a proper bead without further expansion of the tube.

Tube Projection for the Combination Beading Expander

Combination Values needed

As can be seen above, tube projection from the tube sheet is one of the most important things to achieve the perfect bead. This projection is the material which forms the bead within the beading roll. Beware of different tube lengths required to achieve the individual tube projection. Especially on older boilers be aware of tube sheets that may have bowed or warped. Measure each distance on each tube from the outside of each tube sheet then add the projection twice if being beaded on both ends. Tube projection is from 1/4” to 9/32” depending on tube OD and wall thickness.

Consult the PDF Below:

Beaded Tubes

Driving the Combination Expander

Rolling Boiler Tube Expanders

The PTR-03

The PTR-03 is the ideal tube rolling motor to drive the 2.0″ and the 2.1/2″OD combination beading expander.

The Electric Rolling Motor PTR-03 is a powerful, durable and hard-working drive. Designed and manufactured in Germany, this drive motor has been the front runner in many different scenarios. From heavy duty drilling to line boring, the Eibenstock range of motors cover all aspects of engineering when continuous power is needed. Available in either 120 volt or 240 volts and with a Hertz range of 50-60. So, wherever you need power we can provide the correct drive model suited to your supply current. 

The unit features high torque producing power enough to roll 3” OD tubes. Therefore, a machine which is well suited to the pulp and paper industry. With the slow start facility, it has two gears with a load speed of 30-75/90-230 RPM. And, with a change of a switch the drive motor reverses expanders out of the tube with ease. The arbor of the PTR-03 is a morse taper 3 therefore, to make the connection to the expander we supply a mandrel drive accordingly to your needs. This would then be either a ¾” or 1.0” female square.  

When you receive your new PTR-03, you will find it comes with a long reaction bar which we suggest is always used due to its sheer power. Also, a morse taper drift key and the proper operating manual. How reliable we have found this machine we never have had much call for spares. However, if the need should arise, all spares are readily available.