What is the next step after tightening the block's clamp when fabricating a single flare?

After tightening the block's clamp during the fabrication of a single flare, the next logical step involves placing refrigerant oil on the flaring cone. This step is crucial because applying refrigerant oil helps to lubricate the flaring cone, which can prevent damage to both the cone and the tubing during the flaring process. Proper lubrication ensures that a clean and uniform flare is created, which is essential for a tight and leak-free connection in refrigeration systems.

The use of refrigerant oil is particularly important in this context because it reduces friction between the metal of the tubing and the flaring tool, helping achieve a smooth and well-shaped flare. If lubrication is not applied, there's a risk of creating rough or uneven edges on the flare, which can compromise the integrity of the joint.

Following this step is typically the inspection of the flare for uniformity, but that comes after ensuring that the flaring tool is adequately lubricated and has been used properly.