MTS Series 322 Load Frames - Manual (Page 20)

Series 322 Load Unit 20 Introduction
a b
c d
Deflections and Spring Rates
322.21 322.31 322.41
Deflections * 100 kN (22 kip) 250 kN (55 kip) 500 kN (110 kip)
A-B base 0.15 mm (0.006 in) 0.18 mm (0.007 in) 0.20 mm (0.008 in)
B-C columns 0.10 mm (0.004 in) 0.20 mm (0.006 in) 0.20 mm (0.008 in)
C-D crosshead 0.13 mm (0.005 in) 0.20 mm (0.010 in) 0.25 mm (0.10 in)
A-D overall frame 0.38 mm (.015 in) 0.53 mm (0.021 in) 0.66 mm (0.026 in)
Spring rates * 2.6 x 10
8
N/m
(1.5 x 10
6
lb/in)
4.6 x 10
8
N/m
(2.6 x 10
6
lb/in)
7.4 x 10
8
N/m
(4.2 x 10
6
lb/in)
* Determined at each load unit’s full fatigue rating with its crosshead raised 50 in (1270 mm) above
the T-slot table.
Deflection rates can vary 20%, depending on the type of actuator and force transducer you use.
For the most accurate high frequency test results, use a Load Unit with a fatigue rating that is larger
than its actuator’s force rating. (A 322.31 Load Unit with a 55 kip fatigue rating and a 22 kip actuator
will be stiffer than a 322.21 Load Unit with a 22 kip fatigue rating and 22 kip actuator.)