Micronics Portaflow 222, Руководство пользователя

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Portaflow 222 & 333 User Manual Micronics
Page 10 Issue 3.1 Feb 20
In many applications, an even flow velocity profile over a full 360° is unattainable due, for example,
to the presence of air turbulence at the top of the flow and also possibly sludge at the bottom of the
pipe. Experience has shown that the most consistently accurate results are achieved when the
sensors are mounted at 45°with respect to the top of the pipe.
IMPORTANT: DO NOT EXPECT TO OBTAIN ACCURATE RESULTS IF THE UNIT IS
POSITIONED CLOSE TO ANY OBSTRUCTION THAT DISTORTS THE UNIFORMITY OF THE
FLOW PROFILE. MICRONICS LTD ACCEPTS NO RESPONSIBILITY OR LIABILITY IF
PRODUCT HAS NOT BEEN INSTALLED IN ACCORDANCE WITH THESE INSTRUCTIONS.
2.2 Attaching the Transducers
Type ‘A’ & ‘B’ transducers connect to adjustable guide rails secured to the pipe using wrap
-around
chains and mechanically connected together by a steel separation bar. The separation bar also acts
as a ruler to allow the distance between the transducers to be accurately set to the value indicated
by the Portaflow unit.
NOTE: THE USE OF CHAINS TO FIX THE GUIDE RAIL TO THE PIPE CAN BE ELIMINATED ON
STEEL PIPES BY USING THE OPTIONAL MAGNETIC GUIDE RAILS. IN ALL OTHER
RESPECTS THE SETTING UP OF THE SENSORS IS THE SAME AS FOR STANDARD GUIDE
RAILS.
2.2.1 Cleaning the contact area
Prepare the pipe by degreasing it and removing any loose material or flaking paint in order to obtain
the best possible surface. A smooth contact between pipe surface and the face of the sensors is an
important factor in achieving a good ultrasound signal strength and therefore maximum accuracy
.
2.2.2 Assembling the guide rails on the separation bar
1. Slide the separation bar (D) into the front of the left hand guide rail, align the front edge of the
guide rail
with ‘0’ on the ruler scale (E) and secure it in place by tightening the thumbscrew (C).
2. Slide the other end of the separation bar into the front of the right hand guide rail, align the front
edge of the guide rail to the required separation distance (obtained from the Portaflow unit) on
the ruler (F), then secure it in place by tightening the thumbscrew.
NOTE: IF MAGNETIC GUIDE RAILS ARE USED ON STEEL PIPES THEN ONLY THE
LOCATION AT 45° ON THE PIPE APPLY ON THE NEXT TWO SECTIONS.
2.2.3 Fixing the guide rail assembly to the pipe
1. On each guide rail, attach one end of a securing chain to a hook on the tensioning bar (B), wrap
the chain around the pipe (G) and then attach it to the hook on the other end of the tensioning
bar whilst keeping the chain as tight as possible.
2. Rotate the complete guide rail assembly so that it is approximately 45° with respect to the top of
the pipe. Then tighten the chain by turning the tensioning thumb-wheel (A) on each guide block
until the assembly is securely attached to the pipe.
NOTE: IF YOU ARE UNABLE TO GET SUFFICIENT TENSION ON THE CHAIN TO HOLD THE
ASSEMBLY IN PLACE, FULLY SLACKEN THE TENSIONING THUMB-WHEEL AND SHORTEN