Text version of the page

diaphragm valve art.061 petent pending hydraulic characteristics

After a thorough test concerning the needs within the various fields where technical application iscarried out, e.g. the biotechnology and semi-conductor industries, as well as pharmaceutical, food and medical processes, the Ratti snc industry has projected a new diaphragm valve, which allows for clean and sterile handling of the fluid.Through the research of an innovating internal design, a system has been carried out, it includesan option for an open and a closed valve, that is, internal inclined contact surfaces to drain the fluid. This valve makes the cleaning process easy, thusforeseeing a minimization of empty volumes and thetinning of the fluid areas. The valve is completely autoclavable, the body andthe external parts are totally manufactured in AISI316 L, while PTFE support bars file the handle andthe diaphragm. The valve is manufactured in the followingdimensions: from 1/2" to 1.1/2", which includeconnections according to the BS-OD 4825 codes. Whenever the pieces are traced forvalidation, the valve is laser identified,including the production series number,and it is furnished, upon request,with the chemical analysiscertificates of the materials, asobserved in code EN 10 204.1B,and in superficial finishchecking.

The opening and closing movements do not detect theareas which are away from the shutter‚s contact surface,which however, is inclined and it allows the draining of thefluid outwards during the support movement and the tightness of the diaphragm on the work table shutting surface (1).The internal chute allows the valve‚s chamber to easilyempty itself even during horizontal use (2). The inverse taper of the tightness surface in correlation with the diaphragm‚s surface sustain allows for concentrated tightness on the internal edge, which is in contact with the product, it is secured by a strong and optimal compression,and it is performed by the external roller (3). In order toguarantee the maximum quality, the central body is totally machine-manufactured, using welded Tri-Clamp connections, available with internal finishing under 0.8Ra or 0.4 Ra.The diaphragm is manufactured in PTFE, which is appropriatelyconnected to the AISI316L traction-compression systems, therefore there is no possibility of by-passing, and it has a spherical conformation which makes the replacing maneuver easy (4). The runner in the shutter makes anyeventual needs to regulate the fluid more precise (5). Hydraulic characteristics for capacity-loss of loads and ofthe cv coefficient, in accordance with four opening positions of the valves. (7)(4)(3)(1)(2) (2)(1)(3)

RATED DIAMETERCHARACTERISTIC EQUATION∆p = k OPENING K
v C
v • Q
wn

(5) (6)

% (con ∆
p in mbar e Q
w in l/s) (l/s con ∆
p = 1 bar) (US gallon/min)

25∆p = 7927,6086·

Q
2,0362 w

0,3620,42050∆p = 4546,32366·

2,019384

1/2” 3/4” 1” 1.1/2”

Q
w

0,4720,54875∆p = 3837,81323·

Q
2,02509 w

0,5150,597100∆p = 3570,22937·

Q
2,02961 w

0,5340,62025∆p = 2826,21426·

Q
2,00098 w

0,5950,69050∆p = 1613,13217·

Q
2,00278 w

0,7880,91475∆p = 1050,64855·

Q
2,00212 w

0,9761,132100∆p = 916,94085·

Q
2,01877 w

1,0441,21125∆p = 1059,60324·

Q
2,02431 w

0,9721,12850∆p = 390,99972·

Q
2,00014 w

1,5991,85575∆p = 243,10154·

Q
2,00715 w

2,0232,347100∆p = 189,75158·

Q
2,00155 w

2,2942,66125∆p = 153,5007·

Q
2,08601 w

2,4562,84950∆p = 78,20543·

The manual control of the valve is carried out through an ISI316L or PTFE handle, while the automatic control is carried outthrough a single or double effect actuator, including an external shell and a piston, which are manufactured in AISI316L.

Q
2,04348 w

3,4804,03775∆p = 44,79001·

(4)

Q
2,04438 w

4,5685,299100∆p = 34,68208·

Q
2,00486 w

5,3486,204

* The data reflected herein is totally indicative, and it refers to version A regarding the flow, as indicated on the external part of the valve‚s body.

For precision regulation purposes, a manual, self-lockingactuator is available; it includes 80 different positions, as well asa position indicator, which is available only for 1/2” and 3/4” (6). The hole on the head-frame valve allows the externaldisplay of any possible cracks on the diaphragm (7). The valve is able to work in both directions, it is available in two or three different features, and it also provides more additionalvariants based on the necessity of use: 1/2”to 1.1/2" for types A, B and C, in accordance with the BS-OD 4825 codes. Maximum working precision recommended: 150 PSI.

version Aversion Bversion C