Product Details

During long-term operation of plate-and-frame heat exchangers, gasket aging, plate fouling, or seal failure are common on-site problems. The following answers seven typical questions from an operation and maintenance perspective.

Question 1: If there is leakage between plates, what should be checked first?

First confirm whether the clamping dimension is within the range marked on the nameplate. Loose bolts causing insufficient compression force are the main cause of leakage, and the bolts should be tightened evenly in diagonal sequence in several passes to the specified dimension. If leakage still occurs, then disassemble and inspect whether the gasket is displaced, cracked, or aged and hardened.

Question 2: How should the gasket be selected, and what are the operating limits?

The gasket material directly determines the applicable medium and temperature. Nitrile is suitable for media such as water and mineral oil, with a conventional operating temperature of about -20°C to 100°C; beyond this range, EPDM should be selected, as it has good resistance to hot water and steam, with an upper temperature limit of about 150°C; if the medium contains acids, alkalis, or organic solvents, fluororubber should be matched, covering -20°C to 200°C. Choosing the wrong material will accelerate aging and cause leakage.

Question 3: How should plate fouling be handled?

Cleaning should use a chemical cleaning agent compatible with the plate material, circulated at the concentration and temperature recommended by the manufacturer, and then rinsed clean with water. Avoid using tools such as wire brushes to mechanically scratch the plate surface, as scratches will become starting points for corrosion and affect sealing contact.

Question 4: What does an increase in pressure drop during operation indicate?

A gradual increase in pressure drop usually means fouling or foreign matter blockage on the inner walls of the flow channels. First compare the inlet and outlet pressure gauge readings; if they exceed the design value, the unit should be shut down for inspection and cleaning. If the pressure drop suddenly fluctuates greatly, check whether plate misalignment or gasket detachment has occurred.

Question 5: Parameters and applications of the BR-70 type

The BR-70 type has a single-plate heat exchange area of about 0.7 square meters, a design pressure not exceeding 1.6 MPa, and plate materials available in 304 or 316L stainless steel. It is suitable for medium-sized heat exchange applications such as HVAC, district heating, and chemical cooling.

Question 6: What items should be checked in daily inspections?

Record inlet and outlet temperature, pressure, and flow rate every shift; check weekly whether the clamping bolts are loose; compare monthly the trends of pressure drop and temperature difference. Handle any signs of leakage promptly to avoid further gasket damage.

Question 7: What should be noted during disassembly and assembly?

Mark the plate order before disassembly to avoid misalignment during reassembly. Lift plates gently to prevent deformation of the sealing grooves. When replacing gaskets, replace them in complete sections or for the entire unit; mixing old and new gaskets can easily cause uneven stress.