Filling-pressure monitoring system

with automatic regulation of the filling pressure and power of p-joint-sealing cushions/V (valve) during installation.


The sealing efficiency and service lifetime of p-joint-sealing systems are directly related to filling pressure, which is temperature-dependent, and lateral movement along the x-axis.


It is therefore important to:

  • adhere strictly to the installation specification, VO 60.02 Pressure-filling of Sealing Cushions with a Valve for Expansion and Movement Joints, and to provide proof of tightness.
  • reach the permissible pressure filling for reusable p-seals for movement joints (type L: 300 – 350 mbar and type S: 150 – 200 mbar (20°C +10°C)) during installation. This can be achieved by using the filling-pressure monitoring system Art. No. 86.01 p-AK-MSMO, for example.
  • set up the filling-pressure monitoring system Art. No. 86.01 p-AK-MSMO for permanent regulation of filling pressure and power after installation (because pressure fluctuates as a consequence of movement along the X-axis in summer and winter, amongst other factors). Ceiling or wall Installation is recommended.
  • carry out a visual inspection of the filling pressure (tightness) of the reusable movement-joint p-seals in the course of routine joint inspections, adjusting the filling-pressure where necessary.

1 Precision pressure controller

Without internal air consumption
0,1 bis 1,0 bar



  • Pressure setting can be held
    by means of a locknut
  • Pressure flow direction is
    shown by arrows – arrow
    direction shows the
    point of entry

Regulating area:

  • Precise pre-selection
    of working pressure
  • High-resolution
    regulating area,
    for utilisation in
    pneumatic and
    compressed- air


  • Purity class 1
    for compressed air
    in acc. with ISO 8573-1


 Component part


 Top (adjusting knob)

 Zinc – Z 410

 Spring cover

 Zinc – Z 410

 Flexible diaphragm


 Valve pin, complete


 Valve spring

 Galvanised steel

 Thrust spring

 Stainless steel

 O-ring 16 x 2


 Base screw


Flow characteristics:

Regulating range  0 to 1 bar
p2 [bar]          p1 = 8 bar


Regulating range  0 to 1 bar
qn = 20 l/min

Hysteresis of p2 as a function
of rising (falling) p1 at a constant
flow rate of 20 l/min.
Basic setting (starting point)
p1 : 7.0 bar/ p2: 2.0 bar

2 Pressure gauge with diaphragm capsule "Gas"

  • With zero adjustment
  • Optional overpressure and/or underpressure safety
    10 x FSD (full scale deflection)
  • Extremely low  measuring range from 0/6 mbar
  • GOSSTANDART-certified


  • For gaseous dry media that do not attack copper alloys. For measuring gas or steam, it is important that the gauge should be used in accordance with the table "Selection criteria as per EN 837-2"


Measuring element:Capsule spring, CuBE alloy
Movement :Brass
Zero adjustment:From the front
Seal:NBR (perbunan)
Dial:Aluminium, white, with black   markings
Pointer:Aluminium, black
Housing:Stainless steel 304

Instrument glass
Panel-mounted devices
(types D 431/451) Plastic
(acryglass PMMA)

Technical specifications:

  • Type D4
  • Nominal size 100
  • Accuracy class (EN 837-3/6): 1.6
  • Display range (EN 837-3/5):

    NG 63-100 0/25 to 0/1000 mbar,
    and all corresponding vacuum and
    compound ranges with
    over-pressure protection

Application area:
Static load: full scale value
Dynamic load: 0.9 x full scale value
Overload safety: 1.3 x full scale value

Operating temperature range:
Medium:        Tmax  = +60°C
Ambient         Tmin  =  -20°C
                       Tmax  = +60°C


Temperature performance:
Indication error when the temperature of
the measuring system deviates from the
normal temperature of +20°C:

Rising temperature approx. ± 0.6%/ 10 K
Falling temperature approx. ± 0.6%/ 10 K
of the full scale

Degree of protection:
NG 63/160:  IP 33 (EN60529)
NG 100:       IP 54 (EN60529)

Mode of operation of the p-AK-MSMO filling-pressure monitoring system


8          p-AK-MSMO Monitoring system (for pressure filling and monitoring)
            (For assembly unit: reusable p-joint-sealing system)

8.1       Pressure inlet valve

8.2       Precision pressure controller

8.3       Pressure gauge Ø 100 mm     0–1000 mbar

8.4       Connection: pneumatic tubing for connection to the reusable p-sealing system
            (for accessory parts, see PI 60 |05)

8.5       Mini shut-off valve

9         Connection: pneumatic tubing for connection to 85.1 PaK tightness control system (7)
           (Data logging after pressure filling)

2. Functional example
(Fibre Optics CT GmbH
est setup No. 3,
Test Report 263/ 2020)


The following 3 reusable p-joint-sealing cushions (test samples) are connected to one another via the precision pressure controller (8)

5.1     Type L, length lV =   70 cm
          Joint width: 3 cm
          Pressing surface: 9 cm

5.2     Type S, length lV = 409 cm Ø 18.15 cm and
5.3     Type S, length lV = 500 cm Ø 18.15 cm

The precision pressure controller has been set to
250 mbar / 20 °C filling pressure and max. tolerance 300 mbar, in accordance with the required filling pressure for sealing cushions (test sample 5.1/ width 134 cm)

Aim: In order to make the installation process of the sealing system simpler and more economical in the case of joints longer than 30 m, at least two joint-sealing cushions (VV) should be connected to each other and inflated simultaneously in accordance with the installation instructions.


1       Movement-joint seal

2       Slideable weight to
         simulate lateral deflection
         in the movement joint

3       Device for measuring movement

4       Cylindrical pressure load cell

5       Test sample reusable
         p-seal, uncoated

5.1    Test sample Type L       
         width bL 13.5 cm  length lV 74 cm
         volume V =  1863 cm³
         Movement at temperature (20 ± 5 °C): none

5.2    Test sample Type S
         width bL 28.5 cm,
         length lV 409 cm
         volume V = 105766 cm³
         Movement: none   

5.3    Test sample Type S
         width bL 28.5 cm,
         length lV 500 cm
         volume V = 129300 cm³
         Movement: none

Example: Filling times for simultaneous inflation

(Test diagrams taken from FibreOpticsCT GmbH Test setup No. 3
Filling times for test samples A1, A2 and A3, Protocol No. 260.1 /2020)


Test sample 5.1 
Joint width bF        =   3 cm
Pressing area pA    =   9 cm
Length lV               = 70 cm


Test sample 5.2
Diameter:   18.15 cm
Length:          409 cm


Test sample   5.3
Diameter:    18.15 cm
Length:          500 cm


Compressor with pressure
reducer setting 1.5 bar


Precision pressure controller setting
250 mbar, maximum 300 mbar


Total filling time  
approx. 60 minutes


Pressure filling
A1    =   V   =         1863 cm³
A2    =   V   =     105766 cm³
A3    =   V   =     129300 cm³


After approx. 50 minutes
A1 Lateral pressure force 750 N


Example: Pressure force for the purpose of verifying tightness

(Test diagrams taken from Fibre Optics CT GmbH
Test setup No. 3  Test Report No. 263 /2020)


Volume of the 3 sealing cushions:

A1 = 3,0 x 9 x 69 cm    =       1.863 cm²
A2 = 258,6 x 409 cm²   =   105.767 cm³
A3 = 258,6 x 500 cm²   =  129.300 cm³
Total volume                     235.250 cm³

Sealing cushions

1. Pressure filling with air for a total volume of 235250 cm³  =  approx. 60 minutes
For a joint with an average width of 3 cm, this corresponds to
126 x 0.69 m = a total joint length of ~ 87 m

2. After the pressure force was exerted for approximately 2 hours in order to verify tightness,
the pressure was gradually reduced to 225 mbar and then held for ~ 20 min before the test was ended.

Application of the p-AK-MSMO filling-pressure monitoring system (example)


1    Pressure hose Art. No. 33 E-PAS-VAS,
      example of length: 3m

2a  Filling adapter, pressure hose
      with torque plug nipple
       Art. No. 33 EMS-150, length 150 mm

      or alternatively:

2b  Automatic fill-stop
      Art. No. 33 DB-VG8-M8

X   Pressure splitter
      Art. No. 33 TT 570…

           p-AK-MSMO Filling-pressure monitoring system

3.1       Pressure inlet valve

3.2       Precision pressure controller

3.3       Pressure gauge

3.4       Connection to the reusable p-seal

3.5       Pressure gauge shut-off spigot

4          Connector: Art. No. 85.01
            Filling-pressure monitoring system

Wolf GmbH

Zazenhäuser Straße 52
D - 70437 Stuttgart

Tel.:  +49 (0)711 87 39 41
Fax.: +49 (0)711 87 12 30

Email: Service(at)