20
Replacing the sight glass
DANGER
Personnel working on pipes are exposed to
safety risks and may suffer severe injuries,
poisoning or even loss of life.
Make sure that no hot or hazardous
fluid is in the equipment or the pipes.
Make sure that the pipes upstream
and downstream of the equipment are
depressurised.
Make sure that the installation is
switched off and protected against
unauthorised or unintended activation.
Make sure that the equipment and the
pipes have cooled down to room
temperatures.
Wear protective clothing that is
suitable for the fluid and, if necessary,
wear protective gear.
For more information on suitable protective clothing
and safety gear refer to the safety data sheet of the
fluid in question.
You require the following tools to replace the sight
glass:
Combination wrench to DIN 3113, type B (size
11, 17, 18, 19 or 24, depending on equipment
type)
Torque wrench to DIN ISO 6789
Temperature-resistant lubricant is required for
lubricating the system. The lubricant must have the
same properties as OKS 217.
The types of equipment differ in the
number of hexagon-head bolts and
whether they are equipped with an
additional spherical washer.
In GK 11 steam traps, the lid of the sight glass
is fastened with six hexagon-head bolts.
In GK 21 steam traps, the lid of the sight glass
is fastened with four hexagon-head bolts.
A spherical washer is only fitted between the
sight glass lid and the sight glass in GK 21
steam traps.
Otherwise, the same procedure is used for the
different types of equipment.
Slacken the hex nuts (17) in the sight glass lid.
Remove the sight glass lid (10).
In GK 21 steam traps, remove the spherical
washer (16) from the sight glass.
Remove the sight glass seal (15).
Remove the sight glass (11).
Remove the mica disc (14).
Remove the sight glass seal (13).
Remove the second sight glass and its seal in
the same way.
Dispose of the removed sight glasses, mica
discs and seals in accordance with regulations
at the location of use.
