HT-625 material structure

HT-625 identify a new generation of Sliding Bearings dedicated at high temperature. This bearing can be used from –200°C to +430°C. Made in Inconel 625 with a special coating treatment “Duritex ML”. With this material we obtained Plain Sliding Bearings, Washers and special parts based on customer drawings.

Structure of the composite material:

Layer Average analyses of the material Thickness of layer
Sliding Surface Special Surface Treatment “Duritex ML” 0,15 mm (Min)
Supporting shell Inconel 625
  • C = 0,10% Max
  • Mn = 0,05 % Max
  • Cr = 20 ÷ 23 %
  • Mo = 8 ÷ 10 %
  • Co = 1% Max
  • Ta + Nb = 3.15 ÷ 4.15 %
  • Ni = Resto
0,50 ÷ 2,70 mm
  • (Depending on Dim. of the Bearing)

Operating Conditions





Process fluid

Good Very Good Very Good Good Good



  • High load capacity at high temperature
  • Self lubricating
  • Low Static and Dynamic friction factor
  • Minimum wear and excellent life services
  • Easy to mount
  • High chemical inertia

Available Products

The available products made in HT-625 are the Plain Bearings (Bush) ISO 3547 (DIN 1494), the thrust washers and the strips on customer drawing. The material HT-625 can also be manufactured in other different items:

  • Bearing and washers with dimensions on request
  • Special part on customer drawing.

Technical Data

Maximum Specific Load Static 200 N/mm2
Maximum Specific Load Dynamic 100 N/mm2
Maximum Sliding Speed 0,5 m/s (100 fpm)
Friction Factor 0,07 ÷ 0,13
Service Temperature Minimum -200°C (-328°F)
Service Temperature Maximum +430°C (+806°F)
Shaft (Suggested) Stainless Steel chromium plated
Shaft Roughness (Suggested) 0,4 Max

The “Duritex ML” special treatment is resistant to all the oils, solvent, petrol and alcohol, and can stand alkaline and acid solutions.


Base procedure for bushings mounting is to force them into their seats; there are some suggestion to follow:

  • Machine a 1 mm seat lead - in with an angle of 20° (±5°)
  • Clean and burr the pieces to couple
  • Lubricate external bushing surface before mounting
  • Check alignment between seat and bushing centre lines
  • When 2 bushing are needed their junctions must be aligned
  • Use a proper sized mandrel when possible.
  • Mounting can be done with hydraulic or mechanical tools.

The mounting force (F) in Newton is shown in the attached table.

Bushing Nominal Thickness 0,50 ÷ 1,00 mm F = 300 x L (Length of bush)
Bushing Nominal Thickness 1,00 ÷ 1,50 mm F = 500 x L (Length of bush)
Bushing Nominal Thickness 1,50 ÷ 2,00 mm F = 700 x L (Length of bush)
Bushing Nominal Thickness 2,00 ÷ 2,50 mm F = 900 x L (Length of bush)

When mounting larger bushes it is advisable to use a mounting tool to support the bush. The tool diameter should be 0,3 ÷ 0,4 mm more than the bush diameter.

Get Pricesheet And DWG files