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Electrical connection shall be effected by suitably trained
personnel only.
®
Only Boachem
ZXAB and Boachem
supplied with the electric or pneumatic actuator.
6.5
Insulation
If the valve is to be insulated, make sure that the insulation does not
impair the function of the valve. KSB recommends to make sure that the
sealing areas at the cover joints and at the stem passage (gland
packing) are easily accessible and visible.
7
Commissioning / start-up / shutdown
(Please also refer to section 6 Installation)
7.1 Commissioning / start-up
7 . 1 . 1 G e n e r a l
Prior to commissioning / start-up compare the material, pressure and
temperature data on the valves with the operating conditions of the
piping to check the material's chemical resistance and stability under
load.
Surge pressure (water hammer), which might occur, must not
exceed the max. permissible pressure. Safety measures are
required to be taken.
In new systems and particularly after repair, the complete piping system
must be thoroughlyflushed with the valves fully opened so that particles
and / or welding beads that might damage the seat/disc interface are
removed.
If the piping system is cleaned by means of a pickling procedure,
responsibility for the compatibility of the pickling media used and the
pickling procedure itself lies with the pickling company.
Venting the valve by undoing the bonnet/cover bolting or removing the
gland packing is dangerous and therefore not permitted.
To prevent damage to the valve material or joint seals, the usual start-up
and shutdown velocities must be adhered to.
7.1.2 Valve actuation
The valves are closed by turning the handwheel in clockwise
direction and opened by turning it in counter-clockwise direction (top
view direction symbols are found on the top of the handwheel.
Valves with handwheels may only be actuated by
Caution
hand. As the valve can be damaged by applying
excessive forces, it is not allowed to use additional levers to move the
handwheel.
Shut-off valves are normally used in such away that they are either fully
open or fully closed.
For control functions in continuous operation, throttling disc should be
fitted.
Performing throttling operations without a throttling
Caution
disc may result in an excessive noise level,
excessive wear or even destruction of the valve by cavitation.
7.1.3 Functional test
KSB recommends to check the following functions:
Check the shut-off function of the installed valves prior to
commissioning / start-up by opening and closing them several times.
Check the gland packing for leakage when it is subjected to full operating
pressure and temperature for the first time. Re-tighten the nuts (8) at
the gland cover evently, if necessary.
On valves in pressure seal design, the hex. head bolts (7) pre-
loading the bonnet (9) and the joint ring must always be tightened under
operating conditions such that leakage at the bonnet/cover, which
might be caused by the bonnet (9) sinking as a result of low pressure
inside the body (1), is avoided.
The bonnet/cover bolting (7) with the joint ring shall be gradually
tightened crosswise, evenly and in clockwise direction after the first
loading or heating up of the valves and in the event of leakage at the
joint ring. For tightening torques please contact the manufacturer, if
necessary.
Open the valve by two full handwheel turns before
Caution
re-tightening nuts (8), to prevent jamming of the
seat.
Re-tightening the nuts (8) of the bonnet/cover bolting is particularly
important for valves installed in heat transfer systems to DIN 4754.
®
ZYAB can be
7.1.4 Valves with actuator
On valves with electric / pneumatic /hydraulic actuators, the
strokes / actuating forces must be limited.
Electrical actuators are factory-set ready for operation. They shall be
wired as follows:
Globe valve "CLOSE" torque-dependent
Globe valve "OPEN" travel-dependent
The wiring diagrams are given in the terminal boxes.
For pneumatic/hydraulic actuators, the control pressures specified
in the order shall be complied with. Non-observance may damage
the actuator.
Closing and opening torques or actuating forces shall be enquired from
the manufacturer, if necessary.
7.2 Shutdown
In the event of prolonged shutdowns, KSB recommends to drain fluids
which change their physical condition due to changes in concentration,
polymerization, crystallization, solidification, etc., from the piping. If
required, flush the piping with the valves fully opened.
8
8.1
Repair and maintenance work must only be performed by qualified
personnel taking into account the relevant health and safety
regulations.
It is imperative that the below safety instructions and the general
information on safety as per section 2, Safety, be observed for all
servicing and maintenance work to be performed.
valves.
8.1.1 Valve dismantling
Before removing the complete valve from the pipeline or before repair
or maintenance work to the valve itself, i.e.
- prior to undoing the flange bolting between valve and pipe
- prior to undoing the cover/yoke or pressure seal bonnet/cover from
- prior to removing any drain or vent plugs
-
-
- prior to opening the yoke head for maintenance work to the bearing
Servicing / maintenance
Safety instructions
Always use suitable spare parts and tools, even in
Caution
emergencies, to ensure proper functioning of the
the body
prior to undoing the gland cover to replace packing rings
prior to removing an actuator bolted directly to the yoke head
and threaded bush
Valve pressure must be released and the valve must be
allowed to cool down such that the temperature is below
the fluid's
vaporization temperature in all areas in contact with the fluid in order to
effectively prevent any risk of scalding.
11
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