Thomas C. Wilson Tube Tools
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BOILER TUBE EXPANDERS

REFERENCE CHART

Tube Expander Lubrication, Care and Maintenance

The service demanded of tube expanders is severe, therefore, these precision tools require a reasonable amount of care. For long, trouble-free, and economical service, the following is suggested:

  • Remove all rust, mill scale and other foreign matter from the inside and outside of the tube. Foreign matter on the inside of the tube will become imbedded in the tube wall and may cause flaking or galling of the rolls and mandrel. Mill scale or grit left on the outer wall of the tube can cause damage to the tube seat and prevent formation of a pressure-tight joint. Cleaning tube ends is best accomplished with a wire brush or a tube end polisher.
  • Before using, the expander should be washed in a commercial solvent to remove anti-rust, dirt, grease and other foreign matter. Inspect the expander to make sure the rolls and mandrels are free and in good condition.
  • Before using, an expander should be properly lubricated with a pressure resistant lubricant such as Wilson Expander Lube. This water soluble lubricant was developed specifically for tube rolling and may be mixed with water to the desired consistency. For small diameter and light Gauge tubes, immerse the expander in Wilson Expander Lube or a light bodied oil* such as SAE 10 or 20. For large diameter and heavy Gauge tubes, swab or brush the expander with Wilson Expander Lube or a mixture of SAE 40* and graphite.
  • Expanders should be rotated at a speed proportionate to the tube size, Gauge and the length of the tube seat. Tube metal must also be taken into consideration. The proper speed will provide safe cold working of the tube metal without crystallization or flaking. It will also ensure maximum expander life without undue roll or mandrel breakdown. The ideal speed will keep to a minimum mandrel slippage and heating of the mandrels and rolls.
  • After rolling each tube, clean and cool the expander in a solvent or light oil*, then properly lubricate the expander. It is a good practice to use two expanders, if possible, so one can be cooling while the other is being used.
  • Inspect the rolls and the mandrel after rolling each tube. Replace a chipped roll or mandrel immediately! A small chip in a roll can damage the entire set of rolls and the mandrel if not replaced at once.
  • When the job is completed, the expander should be cleaned thoroughly with a commercial solvent or light oil*, and it should be stored in a manner which will avoid the possibility of the parts rusting.
*CAUTION: The presence of oil in the space between the tube and the tube seat can prevent the formation of a leak-tight joint. Do not allow excess lubrication to run down the face of the sheet, so that it can seep into unrolled joints.