©COMEV
AL
V
AL
VE SYSTEMS
Technical Dept. Ref. IOM-DBB MONOFLANGE GLOBE V
AL
VES, UNIFLOW® 8F - Ed.22/03
Comeval V
alve Systems reserves the right to alter any technical data contained in this Manual without prior notice. Regularly updated data on www
.comeval.es
IOM - DBB MONOFLANGE GLOBE VALVES UNIFLOW® 8F
Page 4
ATTENTION!
- When using the valve as an end seal, the employers’ liability insurance association of the gas and waterworks
specifies the use of a safety precaution such as a plug-in disc, blind flange, etc. With a medium jet that freely
exists, you must secure the exit area.
- When installing the valve, there is a crushing hazard between valve and pipe system. Mind the hands to avoid it.
Flanged ends valves:
- Make sure that counter-flanges are compatible with the standard of the valve flanges. When matching up flanges,
avoid gradients, rotation and pipe misalignment that could cause pipe and valve stress and leakage once installed.
Flanges should fit smoothly. Select the proper flange face gaskets according to duty and centre them on the flange
face properly. Do not force the counter-flanges and do not try to tighten the bolts when a gap exists between valve
and pipe or if misalignment is observed. Tighten in a crosswise, moderate and uniform manner.
Screwed ends valves:
- Make sure that the pipe screw has the correct finish and compatible cone for the valve.
- Use proper sealant according to duty, such as hemp core, Teflon, etc.
- Check that pipe introduction in the valve does not exceed its thread, leave a safety margin of minimum 1 mm.
- Tighten with a plain or adjustable wrench on the hexagon end of the valve only. Apply force to other area of valve
may seriously damage the valve. Do not use hook spanners or other wrenches that could damage the hexagon sur-
face. Valve should be threaded smoothly. If not, do not try to force the thread and avoid wrench extensions since this
could lead to breaking the valve or damaging the thread. A general recommendation is not to exceed the tightening
torque of 30Nm.
5.2 Requirements at the place of installation
- Aggressive environmental conditions may reduce the life span of the product. Consider special construction/protective
measures in such a case.
- Consider the interaction between the system and the equipment. Foresee elements to absorb vibrations, pipe dilata-
tions, guides, anchoring and proper support according to the weight of the components.
- The system and operation protocol should be conceived in such a way to avoid high velocities and cavitation. Prevent
pulsing flow or water hammers, which are very harmful for valves and the rest of the components.
- Flooding of the product is not recommended.
- Allow enough space for valve installation, operation and maintenance.
- It is recommended to install a proper sized mesh strainer upstream the valve in order to protect seating surfaces from
abrasion or erosion that could lead to seat leakage.
- Planners / construction companies or the owner are responsible for positioning and installing products.
