DryLin® - Sliding instead of rolling!

Instead of balls (left): Self-lubricating plastic glides (right)

Optimum load distribution

DryLin® linear bearings operate on gliding elements unlike the familiar recirculating ball bearing systems. Thus an essentially larger contact surface becomes available resulting in essentially lower surface pressure. The resultant advantages are:

Shafts and rail materials

Due to the large surface load distribution of the DryLin® linear plain bearings compared to the ball lining, softer shaft materials can also be used. Thus the hard-coated aluminum shafts offer the best friction and wear coefficients, carbon fiber shafts, the lightest weight and stainless steel shafts, the highest chemical resistance. Of course the use of hardened steel and stainless steel as well as hard-chromed shafts is also recommended.

Resistant to dirt, dust and moisture - left DryLin®, right a comparison of DryLin® with ball bearings

Dry run, without lubrication

DryLin® linear bearing systems are designed for dry-running. Your applications are thereby protected against soiling by grease or oil. Even the application under coarse dirt and sand is possible. Particles are repelled from the contact surface by the movement itself. Here the front side of the gliders works like a wiper. The contact surface remains clean.

Low noise

The quiet run is also based on the feature of gliding in contrast to rolling. There is no mechanical rolling up of hard gliding partner and no ball collisions that cause loud noises. The gliding motion is extremely low noise and only a light friction noise is audible.

Rail joint

Maximum stroke lengths

The line up of guide rails (joining) poses no challenge for DryLin® linear guides. The guide rails are slightly chamfered, aligned and simply placed behind each other. The groove resulting from the joint can be passed over by the gliding element without problems. With the DryLin® linear plain bearings, a ball or roller cannot get stuck. In this way stroke lengths of more than 65 feet can be implemented. The assembly is facilitated by the distinct marking of joints provided at the factory.

Permitted speeds/accelerations

DryLin® linear plain bearings do without rolling objects or balls. This makes the bearing independent of the mass inertia of this body and can be used with high speeds up to 33 f/s and accelerations up to 100G. DryLin® linear bearings are thus suitable for applications with light loads, whose cycle rates should be increased. The use of hard-coated aluminum as a friction partner lowers the operating temperature in the bearing due to the high thermal conductivity of aluminum. Thus the operation can be carried out with a high frequency even at very short stroke lengths.
The maximum average surface speed results from the load on the bearings. With decreasing surface load, higher speeds can be achieved. More important than the maximum speed reached is the average speed in a period of time, because it has the most influence on the heating of the bearing system. In cases with breaks between the individual cycles, the maximum average surface speed is decisive, which is achieved during a period of 10 to 30 minutes.

Heat conductivity	[W/m x K]
Aluminium	235
Unalloyed steel	48-58
High-alloyed steel	15

Table 01: Heat conductivity

Average surface speed = Travel distance per cycle [f] / total cycle time [sec].

Extreme application conditions in the offshore sector

Corrosion behavior

The low humidity absorption of iglide® J, J200 and T500 permits even underwater applications. The application of stainless steel or anodized aluminum shafts provide for a corrosion-resistant guide system. Anodized aluminum is resistant to chemically neutral substances in the range pH 2 to 7.

For special cases of application, separate tests are recommended for coated aluminum sample parts for that specific application.

Filling machine, Krones AG, Rosenheim

Chemical resistance

iglide® J is resistant to weak acids, diluted alkalis as well as to fuels and all kinds of lubricants. The intensive cleaning of machines with standard commercial cleaning agents, even in the food sector, is thus not a problem for the guides.

For applications in environments with extreme chemical loads, the application of the DryLin® R bearings equipped with iglide® T500 liners is recommended.

The resistance of linear bearing systems is equally dependent on the counter partner. As a partner most resistant to chemicals, a high-alloyed stainless steel is offered, for instance X105 CrMo 17 (1.4125), or alternatively the use of soft VA steels (e.g. 1.4571).

The iglide® T500 material in heavy-duty use under high temperatures in foundries

Operating temperatures

Gliding elements made of iglide® J and J200 can be used in the temperature range between -40 and +194°F. Bearings with higher accuracy classes could have alternative temperature ranges. Please note the hints on the several product pages. In applications with aluminum shafts and/or rails, distinctly higher loads and speeds can be attained due to the excellent heat conductivity. Gliding elements made of iglide® T500 can be used in the range of -212°F to +482°F.

Self-Lubricating and clean

Use in wood chips