Herculon Modified Type D Bearings (HLMD)
Bearing Pads
Herculon Modified Type D Bearings (HLMD)
Herculon Modified Type D (HLMD) Bearings have been developed to fulfil the need for a simple, low friction, highly stressed bearing on corbels and columns where a continuous slipjoint is inappropriate. They can be used under cast in-situ and post-tensioned slabs and beams.

Materials
Consist of a stainless steel top plate roughened on the upper surface and polished on the lower. This steel plate slides against a Hercuflon coated Hercupad.

Fig 2-4
Types
There are two basic types of HLMD bearings available:
• Standard
• Seismic
The seismic bearings are manufactured from the same materials as the standard bearings, but they have greater all round expansion capacity (±50 mm) to accommodate the larger movements which occur during seismic shock.
Design
Coefficient of friction: 0.05
Expansion capacity: ±20 (standard) to ±50 (seismic) mm
Maximum contact stress: 10 MPa
Maximum temperature: 80°C
Maximum rotation: up to 0.02 radians
*Non standard bearings can be manufactured to accommodate larger expansions and differing rotations.
Installation
Fig 2-5 shows a HLMD bearing being cast into an in-situ roof slab.

Fig 2-5
ORDERING
Table 2-3 (standard) and Table 2-4 (seismic) detail the range of sizes that are available.
Figure 2-6 provides the dimension reference points reflected in the tables.
