Butterfly Valve EUROSTOP LM - Manual and with actuator

Hydraulic test
Each butterfly valve is submitted to pressure test on a hydraulic test bench before leaving the factory, in compliance with EN 12266-1 and EN1074:

• Body resistance and leak test to 1.5 times allowable operating pressure (open valve);
• Leak test on body sides of the disc to 1.1 times allowable operating pressure (open valve).

Tests on the product

• Check of maximum operating torque (MOT) and minimum allowable strength torque (mST) according to EN1074.
• Check of painting: thickness test, holiday test, impact test, MIBK test. Compliance with EN 14901 regulation.

Compliance with regulations

Product:

• EN 1074 - 1 and 2
• EN 593

Factory testing:

• EN 12266-1 (ISO 5208)
• EN 1074

Face to face dimensions in compliance with:

• ISO 5752 series 14

Drilling of connection flanges:

• EN 1092-2
• ISO 7005-2

Control unit connection:

• ISO 5210
• ISO 5211

Body marking according to EN19:

• Nominal diameter in mm (DN);
• Nominal pressure in bar (PN);
• Type of ductile iron;
• Manufacturer logo;
• Model code;
• Melting date.

On the label according to EN19:

• Nominal diameter in mm (DN);
• Nominal pressure in bar (PN);
• Allowable operating pressure (PFA);
• Closing direction;
• Product code;
• Work order, Order confirmation;
• Manufacturer mark.

On the disc:

• Nominal diameter in mm (DN);
• Nominal pressure in bar (PN);
• Type of ductile iron;
• Manufacturer logo;
• Model code.

The marking of the valves manufactured by Saint-Gobain PAM complies with EN 1074-2 and EN 19.

The markings can be integrally cast with the body, or they can be marked on metal plates or labels securely fixed to the body, according to EN 19 specifications.

Size

 The butterfly valves are generally used as isolating devices type on/off. In some particular case, in which there’s low differences of pressure and low flow rate variation can be used like regulating devices, considering the hydraulic parameters necessary to avoid the cavitation risk.

To do the right dimensioning of butterfly valve it’s necessary to know the followings parameters:

• Upstream hydrostatic pressure (that is the hydrostatic pressure with valve in closed position)
• The maximum speed in water pipe (generally expressed in l/s) or the nominal diameter and the project flow rate from which it is gained the speed V=Q/A

Moreover it’s necessary to control that the maximum speed in water pipe have to be equal or inferior to 5m/s, and the exercise temperature have to be between 0°C and 40 °C.

The head loss Δh are variable in function of valve open degree and can be calculated with the following expression:

with Δh = head loss (m), ζ = head loss coefficient (dimensional), v = nominal speed (m/s), g = 9,81 (m/s²)

The head loss coefficient can be estimated based on the first diagram.

Determinates the head loss Δh it’s possible to calculate the flow rate Q in m3/h with the following expression (the same expression can be used to, having the project flow rate Q, to determinate the head loss Δh without using the head loss coefficient):

in which 10,2 is a corrective factor in meters, and Kv is the flow rate coefficient in m3/h, determinable in the second diagram in function of valve open degree.

Example: Valve DN600 mm - Δh = 3 m

From the previous diagram Kv can be obtained = 20000 m3/h. - with valve 100% open- by entering data in the previous formula:

Alternatively, head losses can be calculated when the valve is fully open if the design flow rate Q is known, as a function of the DN diameter, using the last diagram.

Cavitation

If the butterfly valve is only used as a shut-off device, there is no risk of cavitation.

It is possible to use it for adjustment, if the following parameters are considered:

• The opening angle of the valve must remain between 30° and 90° (valve fully open).
• Downstream pressure P2 in meters of water column must be:

P₂ ≥ 0,7 . P₁ - 2,8

with P₁ upstream pressure.

Storage

If possible, the butterfly valve must be located in covered places, as far away as possible from the sun (maximum allowed temperature of 70 °C according to EN 1074), rain and atmospheric agents in general. In addition, the sealing gasket of the valves must be prevented from coming into contact with dust or soil.

Installation

The valve is bidirectional. However, it is advisable to install the valve with the operating element on the hydraulic right side of the pipeline.

The dismantling joint is in the intermediate rest position, allowing the installer to extend it further if necessary. Do not compress it during installation to allow future axial travel, which proves useful for the maintainer to disassemble the valve.
 

Maintenance

The butterfly valve does not need particular maintenance, all parts subject to wear are in fact perfectly self-lubricating.
However, if it remains unused for a long time, it is necessary to check its conditions by performing some opening and closing operations at least once a year.

All maintenance operations must be carried out after the pipeline has been completely emptied (total absence of flow and zero pressure) to avoid any danger to people during these operations.

In the presence of particular operating conditions or damage due to external causes, some maintenance operations may still be necessary. In these cases, the particular construction of the butterfly valve Eurostop allows the gasket to be easily replaced.

Accessories

To adapt the butterfly valves to the different operating and installation conditions, they can be equipped with special accessories in combination with control devices: refer to the data sheet for accessories.

The technical specifications in this document are not contractual and may be changed without notice due to continuous technical progress of the product.