EXPRESS Joint
The EXPRESS joint is a mechanical joint. The seal is obtained by axial compression of an elastomer gasket by means of a gland and bolts. Its main features are:
- assembly without jointing force,
- the ability to orientate the castings,
- its gap and angular deflection.
Range: DN60, 125, 200, 1200 for fittings - DN100, 150, 200, 250 and 300 for pipes.
The seal is obtained by axial compression of an elastomer gasket, by means of a gland clamped by engagement of bolts on the external socket rim.
Description
The socket chamber contains:
- a gasket seat,
- a cylindrical bearing surface to align the spigot,
- an annular cavity allowing angular and longitudinal movement of the pipe or fitting.
The socket has an external rim, which anchors the bolt heads during tightening.
The shape of the gland varies according to nominal diameter.
Both gland and bolts are made of ductile iron.
Range
Pipes and fittings: DN60 to 1200.
Also available in DN1400 to 2000 for link-pipe sleeves.
Applications
Mains above or below ground
The ease of assembly and dismantling of this joint makes it particularly suitable for situations where it is difficult to apply a jointing force: jointing of fittings, overhead mains, laying in congested ground, or in tunnels.
Performances
The joint seal is a direct function of the bolt torque. The values stipulated by must be adhered to.
Resistance to pressure
|
DN |
Class |
PFA |
PMA |
PEA |
|---|---|---|---|---|
|
Allowable operating pressure |
Allowable maximum pressure |
Allowable test pressure |
||
|
DN100 and DN 150 to DN 300 |
C40 |
40 |
48 |
53 |
|
DN60 to DN 300 |
- |
40 |
48 |
53 |
|
DN350 to DN 2000 |
- |
25 |
30 |
35 |
Angular deflection and gap
|
DN |
Allowable laying deflection |
Pipe end displacement |
|---|---|---|
|
D60 |
5° |
- |
|
DN125 (6cm) |
5° |
52 |
|
DN200 to DN300 (6cm) |
4° |
42 |
|
DN350 to DN600 |
3° |
- |
|
DN400 to DN800 |
2° |
- |
|
DN900 to DN1000 |
1.5° |
- |
|
DN1000 to DN1200 |
1.5° |
- |
|
DN1400 |
3° |
- |
|
DN1500 |
2° |
- |
|
DN1600 |
2° |
- |
|
DN1800 |
1.5° |
- |
|
DN2000 |
1° |
- |
The large deflection of EXPRESS joints allows some bends to be eliminated.
The EXPRESS joint allows some gap, enabling it to accommodate small amounts of expansion.
The gap must be regarded as a safeguard and not be used to accommodate repeated backward and forward movements.
The gap and angular deflection accepted by the EXPRESS joint ensure excellent performance in the face of ground movements or undermining by soil scouring.
Standards
This joint complies with technical specifications of standard EN 545 and ISO 2531.
Performance tests advised by this standard have been performed.
The gasket complies with standard EN 681.1.