PRODUCT CODE BPCSDGV

SCIENTIFIC DEVICES (B) PVT. LTD.

INSTRUCTION MANUAL FOR BY - PASS ROTAMETER (BPC SERIES) PRODUCT CODE : BPCSDGH BPCSDGV BPCSDG-OP

CAUTION We advise to go through this instruction manual carefully before installing the Rotameter. Failure to which may cause serious personal injury and/or damage to the Rotameter, for which manufacturer is not responsible.

The details of different parts used in BYEPASS Rotameter are as follows : 1. MAINLINE ORIFICE The use of mainline orifice in the main line is to create the differential pressure. The differential pressure across orifice plate varies with respect to variation in flowrate through the mainline i.e. flowrate can be estimated by knowing differential pressure across orifice plate. 2. BYEPASS ROTAMETER This is basically a inline Rotameter either glass tube or metal tube placed in a Byepass piping. The only difference is the range orifice placed in Rotameter at the inlet. This range orifice is designed in such a way that the differential pressure through the Byepass piping is equivalent to differential pressure across the mainline orifice. With this arrangements. Rotameter in the Byepass piping works as Manometer. 3. BYEPASS PIPING This piping is used to correct upstream tap to the inlet of the Rotameter and downstream tap to outlet of the Rotameter. Isolating Valves used in the Byepass piping are useful to carry out maintenance of Rotameter without shut down.

PRESSURE TAPPING There are three ways of tapping across orifice plate to sense differential pressure :1. CORNER TAPPING (CARRIER RING TYPE) In this case, the pressure taps open at corner of the orifice plate through slots in the carrier ring. Arrangement of Byepass Rotameter with carrier ring for horizontal line is as shown in Fig. (A). FIG. A

1) ORIFICE PLATE 2) BYEPASS PIPING 3) RANGE ORIFICE

4) ISOLATING VALVES 5) CARRIER RINGS 6) FLOAT

7) SCALE 8) MEASURING TUBE 9) PACKINGS

2. FLANGE TAPPINGS This type of tapping is very easy to fabricate as tappings are drilled through orifice flange itself exactly 25 mm away from the face of the orifice plate. It also eliminates the proper distance from the mainline orifice plate for tap locationns. For details on Byepass Rotameter with flange tapping for horizontal line, refer to figure (B) FIG. (B)

HORIZONTAL MOUNTING

VERTICAL MOUNTING

3. The arrangement of Byepass Rotameter with d & D/2 tapping is as shown in the fig. (C). In this case, the upstream tapping is located at the distance D from the face of orifice plate and downstream tapping is located at the distance of D/2, where D is internal diameter of pipeline. FIG. (C)

This scientific device Byepass Rotameter measures fluid flowrates through the pipes of 2” Dia and larger.The orifice plate is located in the main line. A Byepass line including the Rotameter with range orifice is connected to the pressure tapping. Based upon the installation of the Orifice in accordance with B.S. Standard; and installation of the Byepass piping and Byepass Rotameter in accordance with our instructions, the system will indicate flowrates that are correct to within ± 2% of maximum flow. The Byepass Rotameter is supplied in a fully assembled condition. Usually it is designed for mounting in horizontal pipeline.

While installing the Rotameter, please take note of the following points : 1. Ensure that the Rotameter is not damaged during transit. Remove the end plugs and take out the plastic rod which is provided for locating the float at one place during transportation. 2. As the fluid travels through a pipeline, it establishes a flow pattern. Any change in the pipeline configuration caused by a valve, elbow, tee bend etc. , will cause a change in that pattern with resulting turbulence in the flow will cause an error in the meter reading. Hence, it is necessary that the upstream and downstream straight lengths must be maintained as per the table given here below .: FIG. D

FITTINGS BEFORE STRAIGHT LINE

PIPING LAYOUT

DIAMETER RATIO (B) 0.20

0.25

0.30

0.35

0.40

0.45

0.45

0.50

0.55

0.65

0.70

0.75

0.80

10

10

10

12

14

14

14

16

18

22

28

36

46

TWO OR MORE BEND IN THE DIFFERENT PLANE

14

14

16

16

18

18

20

22

26

32

36

42

50

TWO OR MORE BEND IN THE DIFFERENT PLANE

34

34

34

36

36

38

40

44

48

54

62

70

80

REDUCERS OR EXPANDERS

16

16

16

16

16

18

20

20

22

24

26

28

30

GLOBE VALVE FULLY OPEN

18

18

18

18

20

20

22

24

26

28

32

36

44

GATE VALVE FULLY OPEN

12

12

12

12

12

12

12

14

14

16

20

24

30

MINIMUM DOWN STREAM STRAIGHT LENGHTS REQUIRED

4

4

5

5

6

6

6

6

7

7

7

8

8

SINGLE 90º BEND OR TEE ORIFICE

VALUES OF THE STRAIGHT LENGTH ARE IN No. OF ‘D’ ß = d/D d = ORIFICE INTERNAL DIAMETER D = INTERNAL DIAMETER OF PIPE

3. The center of the orifice plate & the pipeline must be in one axis. Beveling of the orifice plate should be towards the downstream end. 4. The pipeline must be clean. It must be flushed through by using a dummy section before installing the Rotameter. 5. The fluid must be filterated & should not contain any particles. 6. The Rotameter must be in a perfectly vertical position. Only ± 2 degree inclination may be tolerated. 7. In case of orifice with D and D/2 tapping our scope of supply included on orifice plate + vertical flanged Byepass rotameter as an indicator. Byepass piping should be provided by user. Byepass piping should be as short as possible & the number of fitting should be minimum. If Isolating Valves are desired, use Ball Valves only as pressure drop across the Ball Valves will be low. For more details on pressure tappings please refer to Fig. (E) given herebelow.

FIG. (E)

ORIFICE PLATE WITH D & D/2 TAPPINGS 8. The pump used by the user should be adequate to overcome the pressure loss across The orifice while maintaining the required pressure through put the system. 9. Ensure that the R.P. line marked on the detachable scale corresponds with Red line on the glass tube. 10. Put the Rotameter gradually into operation to avoid sudden jumping of the float & causing damage to the measuring tube. We recommended the location of floerate control valve on the downstream side 11. Instructions on maintenance of Rotameter are given in a separate manual which is enclosed herewith. Please check the following points, in the event of any problems. Observation

Possible reasons

1. Positive error in a. Deposition of foreign matter in the box of orifice flowrate plate. b. Upstream straight length not enough c. Location of pressure tapping is not correct. d. Deposition on the inner wall of glass tube. 2. Negative error in flowrate

a. Deposition of foreign matter on the upstream face of the orifice. b. Direction of orifice plate reversed. c. Operating pressure not enough to overcome the differential pressure across orifice. d. Pressure loss in the Byepass piping due to needle valve, many ends etc e. Due to presence of internally projecting rivet heads where the flanges between which the orifice plate is mounted, are riveted to the pipe. Downstream straight length not enough. g. Orifice plate bore calculated with wrong pipe I.D. h. Location of pressure tapping is not correct. i. Deposition in the range orifice of Byepass Rotameter.

3. Float of the Byepass Rotameter is stuck

a. Float jammed due to particles in the liquid. b. Flowrate itself is less than the minimum reading specified on

Up at the bottom.

the scale. c. Presence of air bubbles in the impulse piping.