Fluid control system

A fluid control system comprising:

• an upstream side joining block and a downstream side joining block, each comprising a top surface and a bottom surface facing each other, side surfaces extending from the top surface toward the bottom surface side, and an engaging part on the bottom surface side, and defining a fluid flow path and a flow path port of the fluid flow path that opens at the top surface;
• a support member comprising a guide part extending linearly in a longitudinal direction and engageable with the engaging parts of the upstream side and the downstream side joining blocks;
• and
• a fluid device supported by the support member via the upstream side and the downstream side joining block, wherein:
• the guide part constrains the upstream side and the downstream side joining blocks on the support member while allowing the upstream side and the downstream side joining blocks to move in a guide direction;
• the fluid device comprises a body defining a fluid flow path and provided with two flow path ports that open at a bottom surface thereof;
• the upstream side and the downstream side joining blocks each comprise a screw hole formed from the top surface toward the bottom surface side for screwing a tightening bolt that presses a sealing member disposed around the flow path port of the joining block and one of the two flow path ports of the body, that face each other, and connects the body to the joining block;
• the screw hole of the upstream side joining block is formed only on the upstream side of the flow path port of the upstream side joining block in the longitudinal direction;
• the screw hole of the downstream side joining block is formed only on the downstream side of the flow path port of the downstream side joining block in the longitudinal direction;
• and
• the fluid control system further comprises an alignment mechanism formed between the guide part and the engaging part, that utilizes a portion of a reaction force resisting a bending force produced by a tightening force of the tightening bolt on the body and the upstream side and the downstream side joining blocks connected to the body, and acts so as to align the positions of the upstream side and the downstream side joining blocks in a horizontal direction orthogonal to the longitudinal direction of the guide part to a center position of the guide part.