The circular arc skeleton bending technique is used for ridge ventilator. Under normal circumstances, there are three ways to bend the arc skeleton: stretch bending, top bending and roll bending.

The three bending methods of Mcwell's ridge ventilator have their own advantages. The accuracy of the steel roof ridge vent workpiece made by top bending and roll bending of the skeleton is no better than that of the workpiece made by stretch bending, especially the precision of the workpiece made by roll bending. The workpiece will have grooves, and if the strength is uneven, the profile will be suppressed. There are cracks. Moreover, the skeleton deforms a lot, about 50-100mm, which seriously damages the mechanical properties of the workpiece.

Compared with top bending and roll bending, Mcwell's stretch bending is an ideal bending method for the smoke vent rooflight. The stretch-bending machine is developed and manufactured according to the product characteristics of the ventilation building. The working mode of the stretch-bending machine is suitable for the characteristics of the profile frame and ensures the mechanical properties of the profile. The streamlined natural ventilator's profile frame is generally thin-walled rectangular tube or angle steel, and the wall thickness is generally between 2 and 4 mm. The stretch bending machine has a workbench and two movable arms.

When the Mcwell streamlined natural ventilator is performing the bending of the profile frame, the personnel stand on the workbench to perform the bending machine operation. Using the movable arms, about 200,000 Newtons are used to pull the two ends of the profile, but the two ends of the profile frame Pull tight, and then move closer to the mold. The arc skeleton workpiece created by the stretch bending machine has high accuracy and small error, which can be ignored. At the same time, the surface of the workpiece is relatively smooth, no grooves will appear, and the continuous strength is also high.

Compared with thin roof louver vent, Mcwell's ridge ventilator generally have larger throats. However, although the throat of the roof louver vent is small, the ventilation effect is still good, and it is also popular in small and medium-sized enterprise factories.