Function and Description
PROTEGO® WV/T change-over valves are mainly used together with other valves or devices (e.g., PROTEGO® flame arresters) on cryogenic storage tanks and on tanks in process plants in the chemical, petrochemical, and pharmaceutical industries. They increase the operational safety of the equipment to be protected, as each valve or device can be checked, maintained, or repaired without interrupting plant operation.
The valves mainly consist of the housing (1) with flange connections DN 1 and two lateral connection elbows (3, 4) with flange connections DN 2 and the valve disc (2). If necessary, it is possible to off-set and turn the connection elbows. The valve seats (9, 10) are replaceable. The valve disc with metallic sealing surface is movable on the valve spindle (6). This ensures good contact pressure with the valve seats (9, 10) even with high temperature differences. The sealing between the valve disc and valve spindle is done by an O-ring. The valve spindle is guided by bushings and sealed to the outside by an adjustable sealing set (7).
The change-over valve allows the operator to block one valve or device at a time by operating the hand wheel (8). In normal operation, the valve disc (2) is in middle position and the gas/liquid flows through both connection elbows. By turning the hand wheel as far as it will go, one of the connecting elbows (3 or 4) is closed while the other one remains open. The actual position of the valve disc is indicated by the position indicator (5) on the valve spindle.
Depending on the requirements, the position of the change-over valve in normal operation can be in the middle or end position: Middle position, for example, is if a high capacity of relief is required through emergency relief valves controlled in parallel. End position, for example, is with flame arresters that are connected in parallel and can be used or cleaned alternately.
Due to their design and appropriately selected materials, the valves are characterized by their high functional reliability and very good flow rates. All elements are made of stainless steel.
The design of the PROTEGO® WV/T change-over valves allows the following connections to be made in accordance with the variable valve position or other devices with both angle or straight connections without additional fittings.
PROTEGO® WV/T change-over valves are characterized by their simple design, easy handling, the option of quick replacement of components that affect the function, and by their excellent availability and operational reliability. The lapped metallic sealing surfaces ensure a high degree of tightness even in low temperature ranges.
These valves are not flame-proof and do not fall within the scope of the European Explosion Protection Directive 94/9/EC, even if installed in explosive atmospheres.
Based on a hazard analysis with regard to material selection and function, the valves have no potential ignition sources. This enables unrestricted use in potentially explosive areas.
|DN1||80 / 3"||100 / 4"||150 / 6"||200 / 8"||200 / 8"||250 / 10"||300 / 12"|
|DN2||80 / 3"||100 / 4"||150 / 6"||150 / 6"||200 / 8"||250 / 10"||300 / 12"|
|a||780 / 30.71||780 / 30.71||960 / 37.80||960 / 37.80||1130 / 46.12||1450 / 57.09||1650 / 64.96|
|b||250 / 9.84||250 / 9.84||310 / 12.20||310 / 12.20||330 / 13.47||360 / 14.17||415 / 16.34|
|c *||303 / 11.93||205 / 8.07||285 / 11.22||285 / 11.22||367 / 14.98||450 / 17.72||525 / 20.67|
|c **||323 / 12.72||230 / 9.06||317 / 12.48||317 / 12.48||407 / 16.02||483 / 19.01||571 / 22.48|
|d||273 / 10.75||273 / 10.75||324 / 12.76||324 / 12.76||355 / 14.49||457 / 17.99||500 / 19.68|
|e||250 / 9.84||250 / 9.84||250 / 9.84||250 / 9.84||400 / 16.33||400 / 15.75||500 / 19.68|
|f||905 / 35.63||905 / 35.63||1070 / 42.13||1070 / 42.13||1080 / 42.52||1515 / 59.65||1655 / 59.65|
|fmin||810 / 31.89||810 / 31.89||950 / 37.40||950 / 37.40||1170 / 47.76||1360 / 53.54||1470 / 57.87|
|fmax||995 / 39.17||995 / 39.17||1190 / 46.85||1190 / 46.85||1310 / 53.47||1695 / 66.73||2015 / 79.33|
** for connection flange ANSI 150 lbs
|Housing and connection elbows||Steel||Stainless Steel|
Data Necessary for Specification
Service temperature (°C or °F)
Operating pressure (bar or psi)
Tank nozzle DN1 (mm or inches)
Tank nozzle DN2 (mm or inches)
Position of nozzle I, II or III
Selection and Design
Together with the customer our engineers design and specify the valve for the specific case. The relevant plant specification is taken into account when defining the required nominal sizes and connection types. In standard versions the maximum allowable service temperature is +200°C / 392°F under a maximum allowable operating pressure of 6 bar / 87 psi. The device must have sufficient corrosion resistance with regard to the media to be stored or transported. If necessary, designs in special stainlesssteel quality should be selected.
Flange connection type
|EN 1092-1, Form B1 or DIN 2501, Form C, PN 16 , ab DN 200 PN 10||EN or DIN|
|ASME B16.5 CL 150 R.F.||ASME|
Design Types and Specifications
Special devices in heatable design can be used under specific operating conditions:
with crystallizing products or products which tend to form deposits that affect the function
in use under extreme weather conditions in winter (frost), when product vapour might condensate in the undercooled valve, so ice bridges could develop, which could probly block the valve disc