DK178461B1

DK178461B1 - Method for prolonged life of gaskets in plate heat exchangers

Info

Publication number: DK178461B1
Application number: DK201400494A
Authority: DK
Inventors: Jørgen Pedersen
Original assignee: Jørgen Pedersen
Priority date: 2014-09-02
Filing date: 2014-09-02
Publication date: 2016-03-29
Also published as: DK201400494A1

Abstract

In to-day plate heat exchangers, is it often necessary to change gaskets due to hard gaskets around the high temperature corner hole, even if the gaskets are still not fully worn-out. This invention meet the demand, for low maintenance cost, for low consumption of gaskets for plate heat exchangers, at a way, characterized in turning the plates, the plate pack, the gaskets, by 180 degrees, when it is open due to cleaning or inspections or before worn-out.

Description

Method for prolonged life of gaskets in plate heat exchangers.

TECNICAL FIELD

The invention relates to the field of heating systems in particular to plate heat exchangers.

THE PURPOSE OF THE INVENTION

Plate heat exchangers are widely used: In all ships, in all central heating installations, in the industries all over the world.

The invention seeks to reduce the consumption of gaskets in old plate heat exchangers, by increase the life of plate heat exchanger gaskets.

Consequently, the invention also seeks to reduce the consumption of energy and pollution connected with producing and burning of the gaskets.

PRIOR ART

The to-day plate heat exchanger producers’ service manuals for plate heat exchangers:

Re-assembly, when replacing old plates, ensure that the plates are reinstalled in the correct sequence and orientation as stated on the PHE plate arrangement drawing.

The to-day process for maintenance of plate heat exchangers.

In big District Heating systems, (like TVIS in Fredericia), it is necessary to change gaskets every 5 years, due to hard gaskets around the high temperature corner, corner hole, even if the plates are still clean and even if the gaskets are still not fully worn-out.

RELEVANT PATENT DOCUMENTS

GB 1094366A 1967.12.13, describe a method of changing of the interspace of adjacent plates in a plate heat exchanger, by turning of adjacent plates 90,180 or 270 degrees.

GB application 2184826A of 24 December 1985, describe a plate heat exchanger where the adjacent plate are turned by180 degrees.

The WO 03/040643 A1 of 6 November 2001, describe a method to increase the service life of gaskets for plate heat exchangers, by a thin layer of fluoropolymer applied to the gaskets.

DISCLOSURE OF THE INVENTION

The invention relates therefore to a method of reducing the temperature of the gaskets.

A heat exchanger connected to two circuits of fluids, and wherein a first fluid coming from a primary circuit transmits heat energy to a second fluid coming from a secondary circuit.

For an inlet temperature of 90 degrees Celsius and an outlet temperature of 60 degrees Celsius of the first fluid.

And for an inlet temperature of 50 degrees Celsius of the second fluid and an outlet temperature of 80 degrees Celsius of the second fluid, ( counter-current flow) as illustrated by the temperatures in fig. 1 and 2 at the drawing. The flow is from the 90 degr.corner hole to the 60 degr.corner hole, and from the 50 degr. corner hole to the 80 degr. corner hole at the other side of the same plate.

Knowing that the life of a rubber gasket depends on operating temperatures: An increase of the temperature by 10 degrees above 70 degrees will approximately half the life of the gaskets. And, particular for this invention, a reduction of the temperature by 10 degrees will approximately double the life of the gaskets.

This invention meet the demand, for low maintenance cost, for low consumption of gaskets for plate heat exchangers, at a way, characterized in turning the plates, all and every plate, the plate pack, the gaskets, by 180 degrees turn, around the thickness direction of the plates.

By this not traditional way, will the high temperature end of the plates (90 degrees) be changed to the low temperature end of the plates (50 degrees).

For clip-on gaskets, only the gaskets have to be turned.

Turning the plates:

After the opening process and eventually cleaning process, remove the plates by lifting them off the top bar and then sliding out of the frame. Then turn the plates by 180 degrees around the thickness direction of the plates and then replace the plates followed of the clamping process.

As illustrated in the drawing, where fig. 1 shows the plate before the 180 degrees turn and fig.2 shows the same plate after the 180 degrees turn.

As seen, the gaskets around the high temperature hole are hereafter placed round the low temperature hole.

Claims

A method of reinstalling plates in a plate heat exchanger, characterized in that the method includes all the plates, each plate, plate stack and gaskets which are turned 180 degrees about the center axis of the plate heat exchanger and reinstalled by lifting the plates out of an open plate heat exchanger, out of the rack and turn the plates 180 degrees and reinstall the plates.