Limaco ULM-31-HF, Руководство по эксплуатации и установке

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ULM.0.01.000RE_10_08_20
The pipe branch inner diameter
D
shall be at least 100 mm
1
. The pipe branch axis
permissible vertical deviation, ONLY during measuring the level of LIQUID prod-
ucts - 1°.
The pipe branch height
H is measured along its inner surface from the flange to the
opening lower edge. Maximum permissible pipe branch height depends on its diam-
eter. The bigger the diameter, the higher the permissible pipe branch. The formulas
relating the pipe branch diameter and its height are selected based on application
(see para. 4.3).
Use of higher pipe branch may result in occurrence of stray re-reflections and may
hamper the process of measuring. If it is desired to use the pipe branch longer than
the one estimated for application, it is necessary to agree the design with the manu-
facturer. The opening in the roof under the pipe branch shall be no less than the pipe
branch inner diameter. The pipe branch inner surface shall not have irregularities
sized above 3 mm. The stray reflections from irregularities inside the pipe branch
may result in measurement precision and stability impairment.
In case of using the rectangular section pipe branches, the pipe branch height, with
account of the roof thickness in conjunction with the inner structures adjacent to the
roof (stiffening ribs, etc.), shall not exceed the one calculated by the formulas given
in para. 4.3, where the dimension of the rectangle narrow side is put down instead
of the pipe branch diameter.
4.3 Mounting Pipe Branches
The requirements for the pipe branch are based on the type of application. The ap-
plications are divided into two types: with the strong reflected signal and with the
low-power reflected signal.
The applications with the low-power reflected signal include the liquids with capa-
bility for foam formation >1 cm, the tanks with the stirrers, in cases, when the de-
vice beam hits the cone-shaped surface, occurring due to agitation and having incli-
nation above 6 degrees, as well as all bulky materials.
All the rest applications refer to applications with strong reflected signal.
The requirements to the pipe branch for applications with strong reflected signal.
Permissible pipe branch height
H
is calculated by the formula:
5 . 2
 
D H ;
where
H – maximal pipe branch height in mm, D – pipe branch diameter in mm.
Calculations for the common-type pipe branches are given in the next Table.
1 Level transmitter ULM-31А1-HF-F using the adapter (see para. 12.10) allows for installation on
the smaller diameter pipe branches.