The countermeasure of plate heat exchanger plate wear

With the high thermal conductivity of the film, the special flow path formed by the corrugated sheet can make the fluid generate strong turbulence at very low flow rate, so the heat transfer coefficient is very high. At the same time, it has the advantages of compact structure, small pressure drop, low heat loss, easy disassembly and can be characterized by regulating the number or change the flow heat transfer plate to get the most appropriate capacity and effect, has been widely used in various industrial fields.

BR type plate heat exchanger is a kind of heat exchanger which is made up of stainless steel plate and titanium alloy plate, which has the W type or the herringbone plate. By the two adjacent heat exchanger plates which are installed, forming thousands of corrugated cross contact staggered uniform flow around these contacts around the flow, have a strong disturbance, the formation of high heat transfer coefficient [1]. So plate heat exchanger has high heat transfer efficiency and bearing capacity. A factory BR type plate heat exchanger, in 1995 to install the use of the first time in 2006 when the demolition found that most of the corrugated sheet of the bulge has a point or block damage phenomenon, the plane distribution of a certain law. Penetrant inspection, found that some of the damage point leakage.

Background vibration of the environment. When the environment due to the vibration of the machine and other reasons, there is a large vibration source, the vibration transfer to the plate heat exchanger, may produce a small friction between the plates, resulting in the wear of the plate. Countermeasures: as far as possible the plate heat exchanger placed away from the vibration source or take measures to reduce vibration, such as the establishment of rubber damping foundation.

The fluid flow is unstable on the two sides of the frequent opening and stopping device or through the plate. The plate heat exchanger is composed of a fixed point of contact between the plate and the edge of the rubber sealing strip is provided, when the change of fluid flow and pressure, causing the contact point of adjacent two plates of alternating stress and deformation and may cause slight displacement. This is the main cause of fretting wear. Countermeasures: to avoid and reduce fretting wear is to improve the process, reduce the number of equipment to start and stop, as far as possible to reduce the flow rate of fluid flow on both sides of the plate.

From the experimental data, it can be seen that the energy spectrum of the parent material, titanium is 91.63%, oxygen is 7.79%, and the energy spectrum of the wear point, titanium is about 84.05%, oxygen is 12.97%, and the proportion of the composition of the parent material is close. Therefore, it is considered that the damage is caused by wear. Because the contact point between the plates is relatively static, the damage is caused by fretting between the plates.

(1) the failure of titanium plate heat exchanger is caused by fretting wear caused by fretting between plates.

(2) measures to prevent failure include stabilizing process conditions, smooth operation, and reducing the effects of heat transfer on the environment