Leser 411 Instructions De Service page 19

1 Contents
1 Contents ......................................................... 19
2 General........................................................... 19
3 Testing/marking.............................................. 19
4 Pressure ......................................................... 20
5 Function of a safety valve .............................. 20
6 Functional tightness of a safety valve ............ 21
7 Medium........................................................... 21
8 Temperatures of the medium and ambient
temperatures .................................................. 22
9 Choice of spring ............................................. 22
10 Safety valves with bellows.............................. 23
11 Safety valves with blow-down ring ................. 23
12 Safety valves built into installations................ 23
12.1 Open bonnet ........................................ 23
12.2 Regular lifting operation ....................... 23
12.3 Forces acting on the safety valve ........ 23
12.4 Connections ......................................... 24
12.5 Direction of safety valves ..................... 24
12.6 Flow-through ........................................ 24
12.7 Condensation ....................................... 24
12.8 Transfer of vibrations from the
installation ............................................ 25
12.9 Discharge pipe ..................................... 25
12.10 Unfavourable environmental
conditions ............................................. 25
12.11 Leaks caused by foreign bodies .......... 25
12.12 Protection during storage and
transport ............................................... 25
12.13 Corrosion protection............................. 26
12.14 Maintenance ........................................ 26
12.15 Identification of safety valves ............... 26
12.16 Lever safety valves .............................. 26
13 Setting instructions for spring loaded safety
valves ............................................................. 26
13.1 Lifting device H3 .................................. 26
13.2 Lifting device H4 .................................. 26
13.3 Spring replacement .............................. 26
14 Handling ......................................................... 27
15 Supplementary loading system ...................... 28
16 Combined Safety Valve and Bursting Disc .... 28
17 Unexpected conditions ................................... 29
18 Product overview............................................ 29
19 Assembly instructions..................................... 29
20 Disclaimer....................................................... 29
2 General
The following general notes refer to directly
loaded and controlled safety valves (with
supplementary loading system).
To fulfill its function all components of a safety
valve are manufactured to great precision. Only
this precision allows correct functioning. Safety
valves must therefore be handled with care.
Failure could endanger people, animals and
installations. Even with a correctly functioning
safety valve hazards may occur. This has to be
taken into account.
The following risks could ensue:
a.) The safety valve does not work correctly or
is dimensioned incorrectly: the pressure
equipment bursts. Hazard caused by the
bursting itself and by the hot, poisonous
and aggressive medium.
b.) The safety valve
medium escapes: there is a risk of hot,
poisonous and aggressive medium.
c.) The safety valves leaks: there is a risk of
hot, poisonous and aggressive medium.
d.) Other dangers caused by handling the
safety valves e.g., risk of injury from sharp
edges, heavy weight, ...
In order to minimise the risks of these hazards,
the operating instructions must be adhered to at
all times and given
recommendations
instructions have been developed by practical
experience and
stipulated in the regulations.
Sets of rules and standards:
•
Pressure Vessel and Steam Boiler
Ordinance
•
TRD 421, 721
•
TRB 403, 801 No. 45
•
AD 2000-Merkblätter A2 and A4
•
DIN EN ISO 4126
•
Pressure Equipment Directive 97/23/EC
•
ASME Code Section II and VIII
•
API 526, 520, 527
•
Others.
LESER is in possession of the appropriate
product-related certificates to prove that the
sets of rules and standards are fulfilled and that
safety is therefore guaranteed.
LESER is certified according to DIN EN ISO
9001 (Quality Management System), DIN EN
ISO 14001 (Environmental
System) and Module D of the Pressure
Equipment Directive (quality assurance in
production). This ensures that all requirements
for quality and environment are complied with.
3 Testing/marking
After setting and testing, each safety valve is
sealed by LESER or by the expert of an official
acceptance organisation at the customer's
request (such as TÜV, Germanischer Lloyd, ...).
If the marking of the safety valve is applied on
the valve body by means of a marking stamp,
the safety valve must not be damaged by such
stamping. Deformation of the valve may cause
leakage or destruction of the safety valve. Thin-
walled valve bodies should not be stamped.
operates correctly;
priority over the
below. The operating
from the requirements
Management
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