GB2213894A

GB2213894A - Fire resistant pipe seal

Info

Publication number: GB2213894A
Application number: GB8730087A
Authority: GB
Inventors: Eric Gordon Davies
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-12-23
Filing date: 1987-12-23
Publication date: 1989-08-23
Also published as: GB8730087D0

Abstract

A pipe seal, lined with a material similar to the lining of the pipework to which it is fitted is used to reduce or minimise the risk of the pipe seals formed by the liner extensions over the flange faces melting away or blowing out in the event of the pipe joint being overheated as in the event of a fire. The lips or rims on the seal encase the flared liners and are allowed to compressor collapse in the event of them being too wide. When collapsed, the resilience of the seal legs holds the rims against the adjacent flange surfaces. <IMAGE>

Description

Fire Resistant Joint.

This invention relates to a joint to increase the fire resistance of a joint in a lined pipe and other components.

Flanged lined pipework is extensively used in the chemical processing and similar industri to convey fluids that are corrosive, toxic and/or inflammable.

The outer pipework may be of steel or a similar material and the liner may be a plastic type material or rubber etc. The liners are usually inserted into the pipework and the ends are extended out over the flange face. This part of the liner that extends over the flange face is used to make the seal when the flanges of the pipework are bolted together, thus compressing or squeezing together the ends of the liner that extend over the flange face.

However, seals formed in the manner are exposed to the atmosphere and when they become overheated as in the case of a fire, they are likely to soften and deteriorate and melt much sooner than the outer pipework, that may be of steel or similar material.

When these liners and seals do deteriorate and soften, the fluids in the pipework can escape, sometimes under some considerable pressure, and when these fluids are inflammable, the fire risk is increased. If the fluids are toxic or corrosive, additional hazards are involved.

According to this invention a small ring shaped seal, lined with a similar material as the main pipework, is inserted between the two existing flanges.

when compressed to make a seal, the raised edges of the seal contain the sealing surfaces of the pipework, reducing the risk of any escape of the fluids contained inside the pipework.

Should the seal raised edges be too large such that they bottom on the flanges before a seal is effected, the edges of the seal will compress and bend where the seal is thinned out for this purpose.

A specific embodiment of the invention will not be described by way of example with reference to the accompanying drawings in which; cont/ Figure 1 shews a cross section of two lined flanged pipes with the lining material extended over the flange face to form a seal when the flanges are bolted together.

Figure 2 shews a cross section through the seal device prior to being inserted between the two pipe or other flanges.

Figure 2(a) shews the lips or rims of the device. These rims or lips contain the lining material that extends over the flange face to form the seal.

Figure 2(b) shews the region where the sealing device thins out to allow the device to compress locally in theregion of the lips or rims. The body and lips of the seal are made from steel or similar and the lining material is similar to that of the adjacent pipework.

Figure 3 shews a cross section through the assembled sealing device with the lips or rims compressed.

Claims

Clalis.

1. A sealing device, lined with a similar material and the adjacent pipework, comprising two flange liner retaining rims or lips, reduced locally to allow for compression or collapse when tightened.

2. The sealing device as claimed in Claim 1 is designed to fit most forms of seal where the liner extends over the flange face to form the seal.

3. A fire resistant seal cover that protects the parts of the pipe seal from direct heat by totally encasing them. Existing pipe seals are formed by extending out the lining material out over the flange faces. The lining materials are totally encased and protect direct flame and heat.

3. The sealing device as claimed earlier in 1 and 2 will fit many existing pipework systems.

4. The sealing device as claimed earlier will cater for variations of liner extension seals because the lips or rims will collapse or compress when the flanges are tightened up.

5. The sealing device as claimed earlier will encase and encapsulate the seals formed by the liner extensions and limit or restrict their flow when overheated or melted. It will also help to resist the liner extensions from blowing out under pressure, when hot.

Amendments to the claims have been filed as follows 1. A fire resistant seal cover comprising a metallic body and plastic type liner wherein the seal cover will totally encase with the liner in the seal cover and also the lining material that forms the pipe seal. In the event of the lining material being heated as in the case of a fire, the seal cover will entrap any melting or deteriorating lining material that form the seal and will retain it, thus reducing the risk of leakage of the liquids or fluids being conveyed in the pipework.

2. A fire resistant seal cover that has rims or lips that can deflect or adjust to accept variations of lining material that form the pipe seals.

The thinned out parts of the seal cover will deflect or collapse as the flanges are being tightened and adjust to thickness variations. The rims or lips will be held in contact with the flange faces by the resilience of the thinned out sections.