Trao đổi nhiệt của Alfa Laval có nhiều loại, bao gồm trao đổi nhiệt dạng tấm và trao đổi nhiệt dạng ống
Phổ biến hơn hết là trao đổi nhiệt dạng tấm
Definitions
Plate heat exchanger
Assembly of one or more plate packs and its supporting frame. If there is more than one plate pack, connection plates are used to separate them. Figure 1 shows typical components of a plate heat exchanger.
Plate
A sheet of material pressed into a corrugated pattern carrying an elastomer gasket surrounding its periphery and two of the ports.
Plate pack
An assembly of plates clamped together to entity having internal channels in which two or more fluids can be handled.
Port
Inlet or outlet opening in the channel plate, most plates have four ports.
Heat transfer area
The area of the plate, which is in contact with both fluids.
Total heat transfer area
The total surface area of all the plates, which is in contact with both fluids.
Frame
An assembly that provides the structural support and the pressure containment of a plate heat exchanger.
Connection plate
Plate used to separate two or more services in one plate heat exchanger. The plate pack performing such a service is called a section.
Protection sheet
Removable covering for the top and sides of the plate heat exchanger, which provides protection in the event of spray leak.
Section
See “Connection plate” above.
Các thành phần chính của Alfalaval Heat Exchanger
Name plate
1. Space for logotype.
2. Open space.
3. Web site for service.
4. Possible locations of connections. For 3A units location of 3A tag.
5. Space for mark of approval.
6. Warning, read manual.
7. Date of pressure test.
8. Maximum operating temperatures.
9. Test pressure.
10. Max permissible operating temperatures.
11. Max permissible operating pressures.
12. Decisive volume or volume for each fluid.
13. Locations of connections for each fluid.
14. Decisive fluid group.
15. Year of manufacture.
16. Serial number.
17. Type.
18. Manufacturer’s name.
Plates - There are four different types of plates:
• Standard plates, the most common type plate
• Wide stream plates, with enlarged passage for products containing fibres and particles
• Gemini double wall plates, for increased process safety. The plates may be separated for inspection of the inter-plate space
• Double wall plates, not possible to separate for inspection
The plates are identified by one or more markings punched into the plate.
Yêu cầu lắp đặt
Hướng dẫn chung bảo trì trao đổi nhiệt Alfa laval
Plate Sheet material
Even stainless steel can corrode. Chlorine ions are hazardous.
Avoid cooling brines containing chlorine salts as NaCI and most harmful CaCI2.
Inspect the plates regularly, for possible corrosion attacks, especially on a new installation and after changing the running conditions.
Gasket rubber
The storeroom for spare gaskets should be cool and dark. Gaskets must not be stored hanging or twisted or subject to great load.
Stainless steel surfaces
The stainless steel surfaces of the frame plate, the pressure plate and connection plates are glass blasted. Clean with cloth wetted by paraffin oil. Do not degrease the surface!
Lubrication
Lubricate the bolt threads of the tightening bolts with an EP (extreme pressure) grease. for example Gleitmo 800 or equivalent.
Grease the suspension wheels on the pressure plate and the connection plates.
Connection plates – Dismantling
Most connection plates have corners, which easily can be exchanged or relocated. At normal service and maintenance the connection plates need not to be touched only if the plate heat exchanger is rearranged for new duties. In such cases contact your supplier for advice on how to rebuild your plate heat exchanger.
Pressure plate – Dismounting
At rebuilding it may be necessary to remove the pressure plate. In such cases contact your supplier for advice on how to rebuild your plate heat exchanger.
Pressure test after maintenance
Before start up of production, whenever plates or gaskets have been removed, inserted or exchanged,
it is strongly recommended to perform a pressure test to confirm the internal and external tightness of the PHE. At this test, one media side at the time must be tested with the other media side open to the atmosphere. This also applies for the upside and the downside of a regenerative section.
The pressure testing shall be performed at a pressure equal to the operating pressure of the actual unit but never above the design pressure as stated on the name plate.