SAVA Cross-Overs – Enhanced Safety and Reliability

Special cross-over combinations for Safety (Relief) valves

DIN: 25E – 500E / PN 10 – 40
ASME: NPS 1″E – 20“E / class  150 300
PT range: -30 < T < 230/280°C, vacuum 10-8 mbar

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SPEC SHEET
CERTIFICATE
Industrial pipeline equipment featuring blue pipes, valves, and meters from a valve distribution company in Louisiana, isolated on a white background.
Design Features

Design Characteristics

  • full-flow, round bore
  • cavity free (no medium contact of sealing surfaces)
  • tight for years (DIN EN 12266-1)
  • safe exchange of safety valves
  • transflow during cross-over action
  • operation errors impossible design-wise
  • safe backflow of blow off capacity
  • economic combination of different valve sizes
  • TÜV approved

The basic principle of the safety valve exists therein, that dependent on the construction, a least cross section (Amin) is guaranteed during the cross-over phase from safety valve I to safety valve II. Therefore a minimal flow (protection of the vessel) is always given.

Two diagrams labeled sava (sv1) and sava (sv2) showing tailored fluid monitoring solutions with rotating wheels, valves, and pressure gauges connected by pipes.
PT-Diagramm
A line graph titled "general pressure-temperature-diagram" with the x-axis labeled in degrees Celsius and y-axis in bar. It shows various lines representing different sleeve materials and their performance, utilized by

Operating temperatures < -30°C and > 220 °C have to be checked and approved by AZ according to the operating conditions.

Besides the P/T value of the sleeve the limitations of the valve bodies also have to be considered. Please refer to the EN 12516-1 resp. ASME B16.34 in order to choose a proper pressure rating (PN/class). The shown values refer to austenitic stainless steel 1.4408 (A351 Gr. CF8M).

1) For operating temperatures below -10°C low temperature / austenitic steels are required.
2) Sleeve: There are different sleeve materials / compounds available.

Materials

Standard body materials

  • Carbon Steel 1.0619, ASTM A216 WCB
  • Stainless Steel 1.4408, ASTM A351 CF8M
  • Stainless Steel 1.4308, ASTM A351 CF8
  • Unalloyed stainless steel casting (low Temp.) 1.1138, LCC/LCB/A352

Standard plug materials

  • Stainless Steel 1.4408, ASTM A351 CF8M
  • Stainless Steel 1.4308, ASTM A351 CF8

Special materials

  • Alloy
  • Monel
  • Nickel
  • Zirconium
  • Titan
  • Tantal
  • other materials on request
Sealing Systems

Type STD

Detailed image of a mechanical seal assembly with labeled parts including primary sealing type ptfe sleeve, secondary sealing v-diaphragm in ptfe, stainless steel diaphragm, thrust collar, and plug adjustment

Standard sealing for all major applications;
Tmax 230°C

Type FS

Technical diagram of a firesafe (api 607) type fs valve with annotations showing components such as primary sealing (ptfe diaphragm), secondary sealing, and tertiary sealing (graphite packing)

Firesafe sealing (API 607) with graphite packing for additional
stem sealing; Tmax 230°C

Type CA

Detailed diagram of a valve showing different sealing types to prevent emissions, with components labeled such as thrust collar, stainless steel diaphragm, and PTFE packing, provided by an industrial gasket solutions

Chemical sealing to prevent fugitive emission of aggressive and toxic media
with PTFE packing for additional stem sealing; Tmax 230°C

Type FSN

Diagram illustrating the multi-layer sealing system of a pipe, including primary, secondary, and tertiary seals with labeled components and operational temperature specifications for an industrial supply company in Louisiana.

Firesafe safety sealing (API 607) for fluctuating temperatures
with 3x graphite packing (adjustable) for additional
stem sealing; Tmax 280°C

Type FSN-SL

Illustration of a firesafe safety sealing system, type fsn-sl, with labels for primary, secondary, and tertiary sealing components. This specialized diagram incorporates tailored fluid monitoring solutions, indicating materials and design

Firesafe safety sealing (API 607) for fluctuating temperatures
with 3x graphite packing (live loaded disc springs) for additional
stem sealing; Tmax 280°C

Type CASN

Diagram of a chemical safety sealing system with labels for primary, secondary, and tertiary sealing components from an industrial supply company in Louisiana, including detail on materials like ptfe and stainless steel.

Chemical safety sealing for fluctuating temperatures
with 3x PTFE packing (adjustment) for additional stem sealing;
Tmax 230°C

Type CASN-SL

Diagram showing components of a mechanical piping system including switch boxes, a solenoid valve, flanges, and various couplings labeled with technical symbols and directional flow lines for tailored fluid monitoring solutions.

Chemical safety sealing for fluctuation temperatures
with 3x PTFE packing (live loaded disc springs) for additional
stem sealing; Tmax 230°C

Dimensions

For geometric reasons, threads are used in the flange bores in a few cases

Actuation

1 Locking Devices
Pilot valve combinations, pad lock eyelets, linear key conception, indexing plunger arrestor.

2 Plug stem extension
Solid construction in stainless steel with T-wrench, Standard extension 100 mm or 150 mm, non standard lengths are available on request

3 Actuators
Actuators for mounting-flange acc. to DIN ISO 5211

NEW: Pneumatic actuator AIR GEAR for plug valves with high torque =150.000 Nm

4 Ratched coupling
To usw on multiport valves with standard 90° actuator for bigger switchpositions than 90°

5 Cover extension
Solid construction in stainless steel, Standard extension 100 mm or 150 mm high,  non standard lengths are available on request . Hexagonal bolts on adjustment ring freely accessible. Note: Don’t use with sealing FSN/FSN-SL and CASN/CASN-SL