(1) Central ventilation system
The location of the inlet and outlet shafts of the system is roughly at the center of the field. Its main advantages are: small amount of infrastructure and engineering, low capital construction, stable wind flow, convenient power supply maintenance and management of the main fan; its main disadvantages are long wind path, large wind pressure, and small air leakage at the bottom of the well. The air volume of each branch is naturally unevenly distributed.
(2) Diagonal ventilation system
The inlet and outlet shafts of the system are located near the center of the minefield and the boundary of the minefield, respectively, or near the boundary of the wellfield. The former has three wellbores that reach the surface, one of which is the inlet well, and the other two are the outflow wells, called the diagonal two-wing type; the latter has two wellbores that reach the surface, one of which enters the wind and the other returns to the wind. .
1 inch 25mm wide different length highly visible straps with reinforced edges,
Various models of hooks - For a non-marring hold, protecting your cargo and vehicle
Durable- Ratcheting component adjusts the straps from 1ft. to 16 ft. in length to easily and safely secure cargo
LOAD LIMIT - Safe working load limit of 1,100 lbs / break strength of 3,300 lbs
Small Ratchet Straps,Tie Down Straps,Ratchet Strap Pulley,Mini Ratchet Straps,Tire Tie Down Straps
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