Telescopic Seals – Wearflex®

Introduction to Wearflex® Telescopic Seals

Wearflex® Telescopic Seals are airtight seals to compensate large axial movements (100-350mm) at high-temperatures. They are manufactured using prefabricated stainless-steel half-pipe sections inside high-temperature insulation.

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Design of a Telescopic Seal

Features of Wearflex® Telescopic Seals

Made of insulated stainless steel half-pipe sections.
Absorbs large axial movements up to 350 mm
Quick and easy installation
Airtight seals
Prefabricated

Applications of Wearflex® Telescopic Seals

Seals top section of reformer, furnaces/process heaters/boilers where tubes penetrate the roof
Utilized in the chemical and petrochemical industry
Prevents cold air ingress into the radiant section

Telescopic Seals Installed on Furnace Roof

Comparison between Wearflex® Telescopic Seals and Conventional Method

Conventional Method	Wearflex® Telescopic Seals
Utilizes insulation blanket around the tube.	Used when tubes have a large expansion in the axial direction only.

Conventional method is ineffective when tubes have large expansion in the axial direction since it is unable to compensate sections of the expanded tubes resulting in radiant heat loss from the exposed sections of tubes.

Telescopic Seal compensate extreme axial movements whilst retaining the seal on the roof penetration as well as continuing to insulate the expanded tube preventing additional radiant heat loss.

Design and Installation of Wearflex® Telescopic Seals

Firstly, some details are considered such as:

Process temperature
Required cold face temperature
Diameter of tubes
Minimum and maximum movement of tubes

The data are then used to design & fabricate Telescopic Seals in our factories and shipped to our clients.

Telescopic Seals installation is done as follows:

It is installed at pigtail connection and on top of the steel roof.
The upper set of two half-pipe sections (fixed around each tube) moves like a telescope over the lower set (fixed at the roof casing plate).

* Installation within 5-10 minutes.
* Using a screwdriver &stainless-steel jubilee clips.

Reformer Tubes without Telescopic Seals

Parts of the reformer tubes (without Telescopic Seals) are protruding through the furnace roof. These allow excessive radiant heat loss to the environment which equivalates to energy loss and risks to personnel. Ambient air is also ingressing into the furnace through roof gaps, decreasing the efficiency of the furnace.

Reformer Tubes without Telescopic Seals

Reformer tubes (with Telescopic Seals) are now well covered. Previously exposed tube surfaces are insulated, reducing the energy loss and risks to personnel. All gaps between the tubes and the roof plates are sealed, preventing ambient air from ingress into the furnace, and improving the efficiency of the furnace.

Key Benefits

Prevent cold ingress air through the existing gaps resulting in improved furnace efficiency of reformer furnaces/process heaters/boilers.
Compensate axial movements up to 350 mm.
Easy and quick installation.
High temperature resistant
Reduce the possibility of tube damage due to rapid quenching.
Block radiant heat loss on exposed tube surfaces.
Cost effective with very fast payback on investments.
Personnel safety enhancement.