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Mostro Valves

Nuclear power engineering

 - A00

Gate valve A00 (DN 400 – 500)

DN 400 – 500

Technical description

Body made of open-die forging, yoke welded from steel, joined by a bonnet joint. Seats pressed into the body and secured with a seal weld. Sealing surfaces of the seats and wedge hard-faced with a cobalt-free hard-facing alloy (or cobalt alloy). Stem packing and bonnet joint sealing ring made of asbestos-free material. Operated by an electric actuator located outside the containment (or in normal design). The gate valves have an opening for removing the packing under pressure and can be equipped with a bypass.

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Drawings and dimensions

Application

Shut-off valve for water, steam, gases and other media, particularly in secondary circuits of nuclear power plants, but also in conventional power plants and heating plants, seismically resistant, for the operating parameters given in the table.

Operation

Testing

The gate valves are tested with demineralised water for strength and tightness at a minimum of 1.6 times Pp, for operability and seat tightness at Pp (for gas – seat tightness with air at 0.6 MPa). The body-to-flange weld is inspected by radiography and ultrasound.

Installation

The gate valves can be installed in any position regardless of the flow direction of the working medium. Electric actuators are connected to the valve according to ISO 5210 and DIN 3338. It is recommended to install the gate valves in horizontal piping with the stem vertical and the actuator on top.

Connection

Butt-welded according to ČSN and GOST standards. The gate valves are supplied with ZPA Pečky electric actuators; actuators from other manufacturers can be supplied on special request.

Documentation

Operating parameters

Gate valve A00, DN 400 – 500, Pp 4.4 ÷ 12 MPa
PNTemperature (°C)
200226250256300350
Body material
11416
Operating pressure MPa
635,024,624,444,43,93,3
1007,367,16,96,846,445,98
1609,258,958,688,618,117,54

Materials of main parts

Gate valve A00, DN 400 – 500, Pp 4.4 ÷ 12 MPa
Pos.Part identificationMaterial
054Sealing ringExp. graphite
053SealExp. graphite
044Bolt15320
042Nut11
033Stem nut11416.1-42 3046
015Stem14X17H2
Hard facingC1111
017Wedge11416, 1512808X18H10T
014Cover11 41608X18H10T
Hard facingC1111
001Body11 41608X18H10T

Dimensions

Gate valve A00, DN 400 – 500, Pp 4.4 ÷ 12 MPa
DN/dPp (MPa)PNB + CD (max)HLV 1kg
400/4004,463955460325100021602174
6,510021602287
9,016079023502390
450/4004,463955460325100021602224
6,510021602337
9,016079023502430
500/4504,463955530360120023852674
6,510023852882
9,016093524003162
400/33012160911443300100020652480

Other

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