Special Tube Expanders

Linsen Flaring Expander from Airetool

Linsen Flaring Expander

O.D. Range:
1/4 — 2-5/8 Inches
6.3 — 66.7 mm

SR Expander from Airetool

SR Expander

Diesel Engine Expander from Airetool

Diesel Engine Expander

Series PST Pipe Sizing Expander from Airetool

"PST" Pipe Sizing Expander

Collins Expanders from Airetool

Collins Expander

O.D. Range:
1/2 — 4-1/2 Inches
12.7 — 113.8 mm


Linsen Flaring Expander

These special expanders are designed for making tubing connections without fittings. Using a drill press, lathe, or other power-driven tool, the Linsen expander enlarges the end of the tube leaving a .015" clearance for slip-fit and soldering of another tube of the same size. Can be used on copper, brass, aluminum, and thin steel tubing. Always specify tube gauge when ordering.

  • Rolls out tubes smoothly and evenly so it doesn’t distort or buckle the tube
  • Eliminates extra fittings which saves on installation costs

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Expander*    Order Number Tube O.D. Cup Length Shank Diameter (Round)
in. mm in. mm   in mm
AL 250 5518385 1/4 6.3 0.437 11.1 0.250 6.35
AL 312 5146300 5/16 7.9 0.625 15.87 0.250 6.35
AL 375 5146400 3/8 9.5 0.625 15.87 0.250 6.35
AL 500 5146600 1/2 12.7 0.625 15.87 0.312 7.92
AL 625 5146800 5/8 15.8 0.750 19.05 0.312 7.92
AL 750 5146900 3/4 19.0 0.750 19.05 0.375 9.52
AL 875 5147000 7/8 22.2 0.750 19.05 0.375 9.52
AL 1000 5146000 1 25.4 1.000 25.40 0.500 12.70
AL 1125 5147100 1-1/8 28.5 1.000 25.40 0.500 12.70
AL 1250 5147200 1-1/4 31.7 1.000 25.40 0.500 12.70
AL 1375 5147300 1-3/8 34.9 1.000 25.40 0.500 12.70
AL 1500 5146100 1-1/2 38.1 1.000 25.40 0.625 15.87
AL 1625 5147400 1-5/8 41.2 1.000 25.40 0.625 15.87
AL 2000 5146200 2 50.8 1.000 25.40 0.625 15.87
AL 2125 5512247 2-1/8 53.9 1.000 25.40 0.625 15.87
AL 2625 5524547 2-5/8 66.6 1.000 25.40 .562 (Hex) 14.27 (Hex)

* Other sizes may be available. Contact your mdi sales representative for details.

SR Expander

The "SR" Short Reach Expanders incorporate a rapid taper on the mandrel that allows full expansion of a tube with minimum travel of the mandrel. The mandrel is retained at the rear of the expander to shorten the mandrel length which allows use near sharp tube bends. These expanders are made to order so application details must be provided ahead of time.

  • Compact expander allows operation in confined areas
  • Short mandrel length used in "bent tube" applications

Diesel Engine Expander

Diesel engine expanders are a special line of expanders designed for rolling the injector sleeves into the heads of diesel engines. Detailed drawings of the injector sleeve and engine head must accompany the order to insure proper design. These expanders are made to order for each application.

  • Used in manufacturing, re-manufacturing, and repair of diesel engines
  • Expands sleeve against top injector bore in cylinder head forming a tight seal

"PST" Pipe sizing Expander

The "PST" Expanders are designed to true pipe ends and enlarge the pipe end diameter in two easy steps, providing the correct clearance between the pipe O.D. and the I.D. of a fitting before making a silver solder or brazed welded joint.

  • Portable expanders suitable for field work using hand tools or ratchet wrenches
  • Accurate expansion of pipe end using quality hardened parts for greater durability
  • Threaded mandrel allows fine adjustment for accurate sizing of the pipe end

Collins Expander

Collins self-feeding tube expanders are tough, durable, and powerful. These nonparallel rolling, self-feeding expanders are suitable for close quarter tube installation and repair work.

  • Compact design works well in thin tube sheet applications
  • No setup or adjustments make it quick and easy to use
  • Self-contained rolls that won’t fall out

Please contact your mdi sales representative for further information on these products.


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