Standard measuring location

Description

A standard measuring location is a measuring location for universal use, with the properties described below. Standard measuring locations are used in all line types, particularly for the purpose of tracking synchronization and at locations with material elongation.

For each standard measuring location, a matching signal for the tracking ID and the entry and exit length must be provided in the material tracking system.

Typical applications

• as measuring location for tracking synchronization (pinch hole detectors)

• all line types

• thickness and width measuring devices

• roll stands or skin pass mills (not reversing)

Measuring location properties

Name

Enter a unique name for the measuring location here.

Tracking ID

The tracking ID signal is generated by the material tracking system and a change in its value controls the beginning and end of a “tracked part” (e.g. coil) at a measuring location. This means that each time the tracking ID signal value changes, a data file is closed and a new one is started.

It is an internal ID from material tracking, which is represented using an analog signal. Therefore, only analog signals are available in the drop-down window for selecting the tracking ID signal. Text signals are not supported here.

Enable

The Enable option was originally introduced to represent different line layouts or operating modes. However, there are now almost always easier solutions for this, so the default value “Always” is advisable for a new configuration.

Signals are only stored if the measuring location is enabled. If the measuring location is not enabled, the signals assigned to it are not stored and the measuring location is not included in the product file.

A measuring location is enabled by default (“Always”). The measuring locations ML0 (tracking start) and the final measuring location (exit shear) are enabled as a fixed setting. For all other Standard measuring locations and Measuring locations in front of the tracking start (welder), the setting is variable.

The enable setting can be “Always” or “Never”, or can be controlled by a (digital) signal (Enable = log. 1). All digital input signals and virtual signals can be selected. Signal-controlled enable can be used to enable or disable measuring locations depending on operating requirements, e.g. if parts of the line are bypassed or machines are not engaged. The enable signals are constantly checked for changes. If a change of state lasting longer than 2 s is detected, ibaQDR data storage is stopped and then automatically started with the new configuration.

Maximum elongation

This value can be used to specify the estimated or known maximum elongation in % that the material undergoes when passing the measuring location. This value is then used by ibaQDR to calculate the required length resolution at this measuring location to guarantee basic accuracy in the product file.

Typical application: Roll stands and skin pass mills, stretch levelers

Note

The value should be as realistic as possible and an excessively high value should not be selected for safety, as internal resampling is initiated. In a hot finishing section with seven stands, 100% elongation per stand would therefore mean a maximum elongation factor of 2^7 = 128, which would mean that with a target resolution of 1 m the data before the finishing mill would have to be analyzed with approx. 1 cm resolution.

Entry and exit length

For most measuring locations the entry and exit length of the material will be the same as the material does not undergo any elongation. However, on a roll stand or skin pass mill, and sometimes also on furnaces and stretch levelers, the thickness of the material is reduced, leading to an expansion in the length.

The entry and exit lengths therefore differ and so two length measurement signals are required to enable the measured value mapping to be carried out correctly. ibaQDR uses the different entry and exit lengths to stretch the entry material to the final length when the finished product is created by the cut at the exit shear.

When generating the ibaQDR measurement file, ibaQDR checks whether the exit length of each measuring location matches the entry length of the subsequent measuring location.

See also chapter Length transformations in the data file.

Head cut/Tail cut

In case, there is a crosscut shear to be used for crop cuts at strip head and strip tail in front of this measuring location, the value of the cut length can be taken into account. This ensures the correct length-related mapping of the measured values.

Select here the signals which transmit the total cut length of head and tail cuts. If there is no shear in front of this measuring location, select "No cut".

For more information about head and tail cuts, see chapter Reversing measuring location.

Mirror head and tail

Enable this option for a measuring location if the production direction has reversed compared to the previous measuring location. For example, this is the case in beam rolling mills after lateral transportation of the material to the next roller table, where production runs in the opposite direction.