Yes, we have kinds of slot extrusions with various load-bearing capabilities, including for heavy loads. One thing worth appreciating is that the capacity to carry a particular load depends on several factors including the material thickness and the type of setups used to support the structure. What is the distance between the supports? How is the load distribution? Typically, a light-duty T-slot extrusion will carry a lighter load than a heavy-duty extrusion. All in all, the balance between the extrusion and its supports can make a big difference.