Test & measurement S
ince its debut in 1953, ABB’s Pressductor has become the transducer of choice in thousands of steel, aluminium and other metal rolling mills worldwide, where it is relied on for the accurate measurement and control of
roll force, strip tension and flatness. Uses for this revolutionary sensing technology have expanded steadily over the intervening seven decades. Today Pressductor-based force and flatness solutions are a commonplace sight in numerous industrial settings. You will find applications for the same technology maximising product quality and plant efficiency in newspaper and magazine printing presses, plastic film and textile manufacturing plants, as well as road bridges, marine vessels, motor vehicles – and dozens more settings.
A FORCE TO BE RECKONED WITH Hot and cold rolling mills are hostile environments, where metal sheets are routinely subjected to huge pressing forces of thousands of tonnes. Extreme heat, physical shocks, vibration and electromagnetic interference are the norm in these demanding conditions. Until the middle of the last century, this cocktail of challenges made it difficult to measure rolling forces accurately and consistently. Traditional approaches to assessing rolling forces using mechanical strain gauges demanded frequent recalibration and costly maintenance. Furthermore, the comparatively small electrical signal produced by conventional gauges can be plagued by RF and electrical noise interference, making it difficult to reliably extract accurate sensor readings.
In the early 1950s a radically different approach to mechanical force measurement was proposed by Dr Orvar Dahle and his wife Birgit who were employed as researchers at Swedish electrical engineering company ASEA, later to become part of Asea Brown Boveri (ABB). The groundbreaking solution developed by Dahle exploited the magneto-elastic effect, a phenomenon where the permeability of a magnetic material changes when it is subjected to a mechanical stress.
The transducer created by Dahle featured a block of laminated electrical sheet steel perforated by four holes through which primary and secondary windings were arranged at right angles to each other. This arrangement forms the basis of today’s Pressductor.
Alternating current (AC) passing through the primary winding creates a magnetic field in the medium surrounding it. With no impressed mechanical load on the sensor, this magnetic field does not induce a current in the secondary winding. When subjected to a force, however, the changed magnetic field pattern within the core induces an alternating voltage in the secondary
32 May 2025 Instrumentation Monthly
MEASURE OF SUCCESS: CELEBRATING THE 70TH BIRTHDAY OF A TRANSFORMATION IN LOAD CELL TECHNOLOGY
A pioneering 1950s invention that helped measure force, tension and flatness in metal rolling mills has found a wider world of applications, from printing and textile manufacture to shipping, motor sports and constructing offshore oil rigs. 70 years on, ABB’s Marko Sydanlammi explains why ABB’s Pressductor technology still excels in demanding industrial environments where consistently precise force measurement matters.
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76
