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Characteristics and working principle of thermostatic (bimetal) trap
Thermostatic (bimetal) traps are characterized by large subcooling, long life, good energy-saving effects, water hammer resistance, and beautiful appearance. They are widely used in heat tracing and steam transportation pipelines.
The technical advantages of VMV traps are: unique and reasonable structure + high-precision internals.

1. Working principle:
Thermostatic (bimetal) traps work on the temperature difference between steam and condensate. The working principle of the thermostatic trap is the bimetallic temperature sensing element, which deforms as the temperature of the steam decreases and pushes the spool to open and close the valve. When the device is started, low-temperature condensed water appears in the pipeline, the bimetal is flat, and the valve is in the open position. When the temperature of the condensed water rises, the bimetallic temperature sensing element begins to bend and deform, and push the valve core to the closed position, and the valve closes. The temperature of the condensed water drops, and the bimetallic temperature sensing element deforms and returns, pushing the spool to open the valve, and working cyclically.

2. Structural features:
1. The valve body and bonnet are all made of forged steel A105.
2. The valve clack and valve seat are made of special stainless steel. Through heat treatment, the hardness of the valve clack is as high as HRC55, which improves the service life of the trap.
3. Imported bimetallic sheet ensures precise temperature control.
4. The closing system all adopts high-precision line sealing structure.
5. Built-in filter makes the trap work in a clean environment.
6. The back pressure rate is as high as 50% or more.

3. Product advantages:
VMV thermostatic (bimetal) trap valve body and bonnet adopt A105, and the condensate discharge temperature can be adjusted. It has been adjusted to 120-130℃ when leaving the factory.
The thermostatic (bimetal) trap adopts a line-sealed shut-off system, which has no original steam leakage, no noise, good air exhaust ability, fully utilizes the sensible heat of condensate water, and has a good energy-saving effect.

4. Thermostatic (bimetal) trap selection and installation:
The thermostatic (bimetal) trap continuously drains water. Normally, the discharge temperature of SHT16 from the factory is 120-130℃, and the temperature discharged from SHT32 is 140-150℃ (the user can adjust it by himself). Please note when ordering if supercooling is required. The back pressure rate of thermostatic (bimetal) traps can reach 50% (back-end pipeline pressure/steam pressure), which is not suitable for closed recovery systems, but is suitable for pipelines and heating systems to remove condensate. In general, the safety factor is 2-3 times.