Double Tube Heat Exchanger For Pure Steam System
一, Core positioning and selection logic
In pure steam systems, double tube plate heat exchangers are a mandatory recommended selection (especially when using industrial steam as the heat source) for:
The core heat exchange unit of a pure steam generator (industrial steam heating purified water to generate pure steam)
Pure steam sampling cooling, condensation recovery, and temperature control at the point of use
Heating/cooling, online sterilization (SIP) of injection water/purified water system.
二, Structural principle (double tube plate vs single tube plate)
1. Core structure of double tube board
Two independent tube plates (tube side tube plate+shell side tube plate), forming a leakage detection chamber in the middle
Both ends of the heat exchange tube are sealed and connected to two tube sheets (expansion joint+welding)
Complete isolation of shell side (industrial steam), tube side (purified water/pure steam), and leakage chamber
2. Principle of Pollution Prevention
Single tube plate: Once the weld between the heat exchange tube and the tube plate leaks, industrial steam directly enters the pure steam side, and pollution cannot be warned
Double tube plate: Leakage first enters the middle detection chamber, which can be monitored in real-time through pressure gauges, sight glasses, and sewage outlets to block cross contamination at the root.
3, Key advantages of pure steam system application
三. Health Compliance (GMP/FDA/WHO)
Overcurrent material: 316L stainless steel, polished inner surface Ra ≤ 0.4 μ m
Full emptying design: Slope+no dead corner structure, gravity drainage without residue, eliminating microbial growth
Supports CIP (online cleaning) and SIP (online sterilization)
1. Safe and reliable
Double tube plate+independent leak detection, leak warning and no streaming
Overall stress relief treatment, resistant to temperature shock, less prone to deformation and leakage
Fully welded/expansion welded seal, no risk of gasket aging
2. Efficient adaptation to steam conditions
Shell side uses industrial steam (heat medium), tube side uses purified water/pure steam (cold medium), fully countercurrent heat exchange, high efficiency
Multi pass design (2-3 passes), with a flow rate of 2-3m/s inside the pipe, to enhance turbulence and reduce scaling
Suitable for pure steam systems with high temperature (121-160 ℃) and high pressure (0.1-0.4MPa) working conditions
四, Typical application scenarios and configurations
1. Pure steam generator (core)
Shell side: Industrial steam (0.3-0.6MPa, 140-160 ℃)
Pipeline: Purified water (room temperature → 100 ℃+)
Function: Heating and evaporating to generate pure steam, with dual tube plate forced configuration
2 . Pure steam sampling cooler
Shell side: Cooling water (at room temperature)
Pipeline: Pure steam (121 ℃ → condensate)
Function: Safe sampling, online conductivity monitoring, sanitary grade double tube plate
3. Heating/sterilization of injection water system
Shell side: pure steam
Pipeline: injection water/purified water
Function: System heating, SIP sterilization, no dead corners, full emptying
V. Selection and Installation Considerations
五1. Selection Parameters
Material: 316L (overflow) + 304 (shell/legs)
Design Pressure: Shell side **≥0.6MPa**, Tube side **≥0.4MPa**
Design Temperature: ≥165℃
Polishing: Inner surface Ra≤0.4μm, Weld Ra≤0.8μm
Leak Detection: Configure pressure gauge/sight glass/drain valve
2. Installation and Maintenance
Horizontal installation, with a 1–2% slope on the tube side to ensure complete evacuation.
Regularly drain and leak-test the leakage chamber (per shift/daily).
Perform regular CIP/SIP according to GMP requirements to verify no residue.
