Stainless steel liquid distribution head assembly and heat exchanger

The utility model provides a stainless steel liquid distribution head assembly and a heat exchanger. The stainless steel liquid distribution head assembly comprises a stainless steel body, an input pipe, a flow guide head and a plurality of flow distribution branch pipes. The stainless steel body comprises a barrel and an end cover, a body mixing cavity is formed in the area, below the end cover, in the barrel, a plurality of flow dividing branch pipe holes are formed in the bottom of the barrel, and an input pipe hole is formed in the end cover. The input pipe is welded to the input pipe hole so as to input a refrigerant into the stainless steel body; the fluid input channel from the input pipe to the interior of the stainless steel body is provided with a contraction area with the overflowing section shrunk for throttling and pressure reduction. The flow guide head is arranged on the inner bottom wall of the barrel, a flow guide part protruding towards the direction of the input pipe hole is arranged at the