General Information

Using a pliable material in solid ladle to transfer the normal load while permitting rotation has been known since ancient times. The knowledge gained special significance finding quality with respect to durability durable elastomeric material.

Pot bearing consists of a round steel pot with a flat bottom on which it lies unreinforced elastomeric bearing. The distance between the pot and the lid is sealed resilient seal of soft rubber. Elastomeric elements enabled the soft load transfer from the upper to the lower part of the structure.

Elastomeric material enclosed in a pot acts as tough fluid in a hydraulic press. Therefore, it takes a good seal. The slot on the edge of the elastomeric bearing is a circular ring of hard rubber or brass. With deformability elastomer allows | you turn the cover and bearings allow belong to the group of versatile swivel (joint, fixed) beds. Pot bearings combined with PTFE sliding plate allows except tilt and shift structures and are classified in the group of versatile swivel sliding bearings.

Standard deformable unreinforced elastomeric bearings located in a solid steel pot in the operation of the vertical load is greatly increased capacity due to prevented horizontal deformation. The advantage of these beds compared to conventional steel and spherical plain bearings is significantly lower weight and height for the same payload as well as cost-effective maintenance.

Fixed bearings allow

Scope

In opening remarks highlighted the possibility of turning the lid of the pot in all directions. Fixed Pot bearings are suitable for use where they previously used heavy steel spot swivel bearings. A special feature of pot bearings consists in the possibility of accepting a large load and uniform distribution of pressure on the substrate. Moreover achieved good resistance to aging tires because the elastomeric plate fully protected in the pot with the lid of the impact of ultraviolet radiation and ozone.

Elastomer type and composition of the rubber compound is designed so as to ensure high resistance to ozone and other common atmospheric influences. Pot bearings can be used at temperatures between -30 ° C (243K) and +70 ° C (343K).

Vertical load
Elastomeric panel

Vertical load is transferred by rubber sheets enclosed on all sides, which in these conditions behaves as tough fluid and transmits the pressure on all sides equally. The maximum permissible vertical load on the elastomeric plate is 25 MPa.

Steel pot

Dimensions of steel ring are followed by the internal hydrostatic pressure in the tire. This is not taken into account for the bottom of the pot. For sizing connection between the ring and the bottom of the pot, takes into account the shear force and torque from the internal hydrostatic pressure.

Horizontal load

Horizontal forces are transferred from the upper beds in the lower part of the bed through the ring of the pot. It can be assumed that the horizontal force is distributed to half volume in the form of parables.
The sizing of welds between the ring and the bottom of the pot is taken into account shear forces and moments caused by action of horizontal forces.

Rotate

Due to structural bending over beds leads to rotation of the upper part of the bearing in relation to the lower part and the non-uniform pressure on the elastomeric plate.
Due to the rotation occurs torque.

• al - austenitic sheet
• b - elastomeric gasket
• D₁ - the length of the bottom panel
• D₂ - the length of the bottom panel
• gkp - upper sliding plate
• l - pot
• gz - rubber protection
• h - the height of elastomeric panel
• d - diameter of elastomeric pane
• p - cover
• t - teflon platea
• B₁ - the length of the upper sliding panel
• B₂ - The width of the upper sliding panel
• m - the brass ring
• e - elastomeric panel

Moment caused by the horizontal forces are taken into account in the calculation of pressure on the bearing surface. When transferring horizontal forces from the bed onto a concrete surface should be calculated with a coefficient of friction of μ = 0.5, whereby to obtain the friction force takes the most unfavorable combination (Ft = μ Vmin).
Minimum factor of safety against sliding is taken v = 1.5. If the resulting horizontal force can not compensate for friction bearings must be anchored.

Installation

When installing pot bearings, make sure that the concrete above and below the bed has a high strength M > 45 MPa, while sizing basis for the pressure of 20 MPa.

Bearings are fastened with four screws symmetrically arranged on the bottom panel. Screws are placed the previous and after the bearing is mounted nuts and kontramaticama. At the end of the bed subject to cement mortar.

If the planned horizontal forces can take friction, anchoring can be omitted. Bearings without anchoring shall be the basis of cement mortar. The cover is attached to the pot adjusting screws, which are so dimensioned that are broken after installing the first pivot bearing structure above, and if possible they should be removed after the installation is complete.

Fixed bearings allow products to the standard sizes shown in the CATALOG.

Pot plain bearings

Pot bearings in combination with steel sliding plate and PTFE sliding plate can be versatile and moving unilaterally moving slide bearings . At the bottom of the steel pan (I) was placed elastomeric plate (s). On the edge of the rubber gasket is inserted plates made of hard rubber or brass (m ) . The board receives rubber cover ( P ) . The distance between the pot and the lid is closed with an elastic rubber seal (b). The upper surface cover (p ) is embedded Teflon sliding plate (t ) with pockets that are filled with lubricant . According to the upper surface of Teflon sliding plate sliding upper sliding plate ( GKP ) .
Sliding surfaces are made of stainless steel.

Upper sliding panel on the bottom of the coated plate of austenitic sheet ( al ) of a thickness of 3 mm and the roughness of < 5 µm.
Sliding surfaces and other parts are important for the functioning of the beds are protected from dust by ribbed rubber lining ( gz ) .

Pot plain bearings are secure and fixed bearings allow , anchor bolts on the bottom panel. The upper sliding plate are open for suspension tight and anchor bolts to attach the upper part of the structure.

Installing rails in one direction on the sliding plate in a versatile sliding bed gets unilaterally moving bed . Pot plain bearings are suitable for installation in complex structural solutions bridges.
Pot plain bearings have low height and low weight compared to conventional steel sliding bearings , low friction sliding and easy inspection and maintenance.

The bearings are designed so that the parts subject to wear can be easily replaced . Bearings are factory set to the desired shift . Before pouring the screws for adjusting going on and open the closed wooden pegs .
This sliding plate during concreting not move , and the bed is fixed to the hull adhesive tape . For fixing beds in concrete serve four screws at the corners. Red assembly is the same as pot bearings . If before concreting is not possible to download the set screws , used plastic screws that are broken in the first rotation . With versatile sliding bearings where the friction force at the junction of bed - base 1.5 times the horizontal force can be anchoring omitted.

Marking bearings

Finished up bearings are designated according to their nature and purpose. In addition to labels manufacturer specifies the type, size and movability. When moving beds indicates the direction of displacement, and special devices and the size of displacement. All these labels are visible and lasting for a long time.

Quality assurancee

Manufacturer takes care of maintaining the quality, durable conducting performance test and bearing dimensions or their individual parts. In addition to its own investigations, the manufacturer conducted periodic tests of a competent institution.

When a manufacturer supplies a certificate of safety products issued by the competent institution which conducted control tests and conducts continuous monitoring of product quality.