 Industrial
Valves by Gestra
As a major distributor for Gestra, Valutech has been supplying
industrial valves - continuous and intermittent boiler blowdown
valves and check valves for the boiler and
fluid control industries.
Boiler Blowdown Valves
Since all boiler feedwater contains some solid impurities due to
the evaporation process, i.e., the boiler-water density (TDS level)
increases, the boiler-water TDS level or conductivity has to be
kept within permissible limits. Gestra provides two possible solutions
or operations which together guarantee optimum boiler safety and
trouble-free operation.
 Continuous
Blowdown
The most effective blowdown operation (dissolved-solids removal)
is obtained by a continuous process so that the minimum quantity
of water is discharged from the boiler. The Gestra continuous
blowdown valves (Reactomats) type BA or BAE were
specially designed for this purpose. These robust valves are of
compact design and easy to operate. The essential part of the valve
is the GESTRA multi-stage nozzle or - for larger blowdown rates
- the radial stage nozzle serving as discharge and control unit.
The nozzle allows the water withdrawn from the boiler to expand
and flash gradually across each successive orifice area and expansion
chamber. The flashing effect reduces the blowdown velocity and virtually
eliminates the risk of wire drawing. The noise level of the valves
is therefore very low.
 Intermittent
Blowdown
If boiler feedwater is treated by a simple process slight amounts
of alkaline earths penetrate into the boiler water (residual hardness)
requiring resoftening in the boiler in the form of phosphates by
ensuring a well-calculated phosphate surplus. The phosphates form
a sludge layer on the heating surfaces and in the boiler bottom.
Sludge deposits will accumulate to form a dangerous insulating
layer of scale on the heating surfaces and reduce the rate of heat
transfer. It is therefore necessary to discharge the sludge at regular
intervals i.e. to carry out intermittent blowdown.
Residual hardness complexation with polyacrylates in spite of its
dispersing effect also requires intermittent blowdown. although
hardening constituents are kept in suspension by the polyacrylates,
after a prolonged period they are nevertheless precipitated in the
boiler bottom. All sludge deposits are a risk for boiler safety
and should therefore be removed by intermittent blowdown at regular
intervals for periods of 1 to 3 seconds (or longer if preferred).
 Check
Valves by Gestra
As a major distributor for Gestra, Valutech has been providing
check valves for the heat and process fluid control industry for
well over a decade.
The Gestra check-valve range includes gravity circulation checks,
non-return valves, swing check valves and dual-plate
check valves. All valves are water pattern and have extremely
short overall lengths.
Due to these design features the valves offer the following advantages
in comparison with conventional valves:
- Compact design
- Minimum weight
- Installation in any plane
- Low installation cost
- Wide range of materials
- Space-saving stock-keeping
Due to rarefined manufacturing technique and their excellent hydrodynamic
properties Gestra check valves make a valuable contribution to the
safe operation of industrial plants.
Gravity Check Valves Gravity circulation checks are used to prevent
gravity circulation downstream of circulating pumps in heating and
hot-water installations.
Applications for Gravity Circulation Check Valves
- For sanitary and HVAC (heating, venting and air-conditioning)
applications
- For heating and hot-water systems, liquids, vapours and gases
- Can be used as a vacuum breaker, as a pressure relief valve,
or for air venting
- For installation between two flanges
Applications for Non-Return Valves
- For liquids, gases and vapours.
- RK41 is particularly suitable for heating systems.
- RK44 for sea water and drinking.
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