Safety with the RBU spectacle sliders

The RBU gland valves are used where a 100% seal of gas pipes is required. Even in the event of a power failure, the seal is maintained by the goggle valves, so that complete safety is guaranteed at all times in accordance with the provisions of the accident prevention regulations (UVV).

The sealing corresponds to a blind flange closure. The pressure is generated by spring elements and is therefore independent of an external energy supply. To move the gland and open or close the line, the press frame is released from the sealing flange hydraulically or electrically.

Depending on the customer's requirements, the RBU spectacle slides can be supplied in an open or closed design. In a closed version, the housing can be heated to prevent condensation.

They are mainly used in metallurgical plants, in the chemical and process engineering industry as well as in power plants. In general, however, our gland valves are best used where the gas-tight shut-off of pipelines is necessary.

Key Facts

Maximum pressure: 200mbar
Operating temperature: up to 200°C
Size: DN600 to DN3500
Design: closed or open design
Sealing: soft sealing, with axial compression
Actuation: Handwheel, electric or hydraulic

Complete sealing

Our spectacle sliders consist of two frame parts that are firmly connected to each other via bridges. The sealing frame is mounted on guides and can thus be moved axially, which allows for a smooth change between open (hollow disc) and closed state (blind disc) when retracted. In the pressed-on position, the dummy disc effects a gas-tight closure of the pipeline cross-section, while the hollow disc completely frees it. Since no parts of the slide valve remain in the pipeline system when it is open, the pressure loss corresponds to that of a smooth pipe of the same length.

The RBU spectacle slides are soft-sealing. This means that sealing is achieved via elastomers, i.e. elastically deformable plastics. A circumferential, all-round rubberised shut-off wedge is installed in the closing body, which can compensate for unevenness in the casting and minor impurities, for example, so that a complete seal is ensured. Soft-seated gate valves are characterised not only by their sealing ability but also by their long service life and freedom from maintenance.

Minimal Maintenance required

Due to the very low maintenance requirements, the RBU gland valves are an investment for the future. All moving parts are easily accessible and are located outside the pipeline where they cannot come into contact with the dust-carrying medium. Sealing surfaces and gaskets also show hardly any wear, as they cover themselves in a self-protecting manner both in the open and closed gate valve position. Lifting the seals off the sealing surface before each adjustment also prevents abrasion of the seals.

Customised for your requirements

We offer a variety of different versions of our spectacle slides, depending on your requirements. The size of the gate valves ranges from DN600 to DN3500. DN stands for nominal diameter (from the French diamètre nominal) and is the European and international designation for the inner diameter of a pipe and the connection dimension of a fitting such as the RBU gate valves. The number roughly describes the inner diameter in millimetres. Our RBU gate valves are therefore roughly suitable for pipeline systems with an internal diameter of 60 centimetres to 3.5 metres.

Areas of application for our spectacle sliders

Especially in the case of blast furnace gas and converter gas, a 100% seal is of utmost importance, as both gases consist of high proportions of carbon monoxide. In the case of blast furnace gas, it is around 20 to 30 percent by volume, while converter gas, which mainly escapes from the converter during crude steel production using the oxygen blowing process, even has around 65 percent carbon monoxide by volume. Our goggle valves therefore not only contribute to the functionality of the plant, but also immensely to the safety of the people working there.

The advantages at a glance

100% tight seal (blind flange)

Smooth-running and insensitive to dust

Particularly easy to maintain and low maintenance


No wear of the seals and sealing surfaces

No pressure loss when the valve is open

Temperature insensitivity up to 200 °C

Wide range of installation options

Customer-oriented total solutions from a single source

At RBU, you don't just get the product itself. We offer you the complete package including delivery of associated systems such as pipelines or maintenance platforms. We are also happy to carry out the installation according to your specifications.

Contact us and upgrade your installation with a spectacle slide from RBU.

To the contact pageanfrage@rbu-germany.com