Description; Principle Of Operation; Load Carrying Capacity - SKF HMV Série Mode D'emploi

1. Description

1.1 Principle of operation

Figure 1. Parts of the hydraulic nut
The hydraulic nut has proved to save considerable effort when mounting or dismounting
rolling bearings with tapered bores. It comprises two main components: a steel ring
(fig. 1a) with internal thread and a groove in one side face, and an annular piston (fig. 1b)
that rests in the groove. The seal (fig. 1c) between the two parts consists of two O-rings.
When oil is pumped into the pressure chamber (fig. 1d), the piston is pressed out with a
force that normally is sufficient for mounting and dismounting rolling bearings. The outer
ring is provided with an unthreaded hole (fig. 1g) to hold a dial indicator (fig. 1h).
The measuring tip of the indicator will rest against the shoulder of the piston to indicate
axial travel.
(Note: The drive-up distance can be used to determine correct mounting; see skf.com/
mount or download the SKF Drive-up Method Program at skf.com. Alternatively download
the SKF Drive-up Method app on the App Store or on Google Play™).
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Two threaded holes are provided in the steel ring for attachment of the hose from the
pump: one in the side face (fig. 1e), and the other in the circumference (fig. 1f). The hole
that is not in use must be plugged with a ball plug, which is supplied with the nut.
The hole used for the hose connection should be fitted with a 729832 A nipple, included
with the hydraulic nut. A spare set of O-rings, a maintenance set, and a tommy bar for
tightening the nut are all included as standard accessories.

1.2 Load carrying capacity

SKF hydraulic nuts are designed to withstand the pressure normally encountered when
rolling bearings are mounted or dismounted.
SKF HMV / HMVC 5