HBK HBM Bruel & Kjaer U10M, Инструкция по монтажу

Страница: 19 / 278

17
U10M, U10S
MECHANICAL INSTALLATION
ing diameter corresponds to dimension P, the admissible centering depth is 3mm
(
see Page 48ff ).
S
The anti-screw-through device attached to the internal thread of the adapter must not
be removed.
S
The (customer-side) external thread must comply with a thread tolerance of 6g for
metric threads and 3A for UN/UNF threads.
S
The threads must be cleaned of any deposits and soaked with graphite-free grease
before being screwed in.
S
The following applies for steel force transducers (nominal (rated) forces from
12.5kN): To achieve the full endurance strength, a material with sufficient
tensile strength (min. R
p,0.2
= 900 N/mm
2
) and hardness (min. 40HRC) must be used.
We recommend the use of threads rolled after heat treatment for measurement
ranges between 225kN and 500kN.
If the customer fits their own force application parts in the U10, and these have a differ­
ent coefficient of thermal expansion from that of the measuring bodies (e.g. a steel
thread in an aluminum measuring body), and if these are fitted tilted or uncentered, ther­
mal stress may be produced during temperature variations that may adversely affect the
temperature dependence of the zero point due to irregular deformation. In this case, to
ensure precise measurements we recommend centering using centering dimension “P”,
and using a nut that ensures a right angle for locking (e.g. by grinding the nut).
Alternatively, the connecting part could be designed so that it is fitted without locking
using centering dimension P. This is possible whenever the connecting structural ele­
ments can be mounted using the "Pre-stressing with defined tightening torque" method
(
see table Tab. 7.1, page 19 ). This is the case for all nominal (rated) forces up to and
including 25 kN.