Axial on-off valve

This valve is specifically suitable for severe duty on-off (upstream) and for quick-acting safety applications (HIPPS, ESD). Pressure has no impact on the operating forces, and the valve can be opened against full differential pressure.

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Facts

Axial flow

Streamlined flow path through the full-port expanded body avoids turbulence and prevents erosion and vibration. Process downtime and maintenance costs are reduced.

Low pressure loss

The capacity of the axial on-off valve is extremely high, as a result of which the pressure loss is negligible. Operating costs of pumps and compressors are reduced.

Pressure balanced

Operating forces are independent of pressure. Valve can be opened against full differential pressure without damage to sealing. Equalisation with a bypass valve is not required.

Easy actuation

Actuation force is low and constant because of pressure-balanced trim. Small, spring-opposed actuators can be selected and gearboxes are not required.

Excellent sealing

In the open position the main seal is protected against erosive flow. The self-energising sealing system offers reliable bi-directional and bubble-tight shut-off (class VI).

Compact

The one-piece valve body provides 15-60% weight reduction compared with ball or gate valves. This benefit is even more attractive combined with spring-opposed actuators.

Fire-safe

The seals that prevent internal and external leakage are secured inside the valve body and therefore less susceptible to external heat sources. All axial on-off valves are certified fire-safe.

Product Summary

Type designation
Safety shutdown valve or isolating valve
Model
RZD - X
Scope
Sizes: 2" - 72"
Ratings: ASME 150 - 2500 or API 3000 - 10 000
Higher pressure ratings upon request
In preference to
Ball valve
Plug valve
Gate valve
Typical applications
Severe-duty on-off (upstream)
Quick-acting on-off (HIPPS, ESD)
Flow line and header on-off
Critical isolation, start-up and blow-down
Switching valve (mol sieve)

Video 48" on-off valve

Manufacturing a 48" Axial on-off valve, made to customer specifications

Axial on-off valves, The Netherlands
Axial on-off valves, The Netherlands
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Axial on-off valves (HIPPS), South Africa
Axial on-off valves (HIPPS), South Africa
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Can we help?

If you would like to have more information about this product, please contact us. As experts in engineered valve systems, we are capable of providing reliable customer services and can support you with valve sizing and selection, process engineering and system lay-out and budget pricing.

Special features

  • Custom-designed
  • Safety: secured process isolation by means of reliable on-off technology (HIPPS)
  • Very fast stroke times : 20” Class 1500 in less than 2 seconds.
  • Suitable for infrequent use: operating forces do not increase over time. No-sticking.
  • Hydrogen (H2) ready
  • Full range of matching Mokveld pneumatic and hydraulic actuators with tailored control arrangements is available. Electric and electro-hydraulic actuation is also available.

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Product support

In order to ensure you continue to benefit from valves that offer high capacity and safety as standard, our Product Support team offers a range of services to improve your valves in use and to achieve cost savings. 

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