Relevance

Holes in stainless steel workpieces are mainly made by drilling. In this case, the hole will never be perfectly flat cylindrical shape. In cross section they have an oval shape, and in the longitudinal - a cone shape. The diameter of the drill is always smaller than the diameter of the finished hole in the metalwork. This difference is called the hole breakdown. For a drill with a standard diameter of 10 to 20 mm, the breakdown rates vary between 0.15-0.25 mm. The reason for the breakdown of the drilled hole in stainless steel products can be factors such as insufficient sharpening of the drill, deviations in the axes of the drill and spindle on the drilling machine. If the accuracy is achieved in the range of 12-14th quality, then the drilled hole in metal products is not subject to further processing.

Increasing accuracy

This can be achieved by countersinking. The holes made using countersinking acquire the specified shape and a more accurate diameter. This is a machining process that gives a hole accuracy of between 10 and 11 grades. Reaming is used to achieve the highest grade accuracy of the drilled hole. This post-processing brings the shape and diameter of the cylindrical hole to between 6 and 9 degrees, with a roughness Ra of 0.32 to 1.25 µm, which is very good.

Drills
Drills, which are used to produce blind or through holes in stainless steel metal structures require periodic machining on turret lathes. Metal drill bits themselves can vary in purpose and design. In structural materials such as stainless steel, cast iron, etc., drilling holes are performed by special drills with conical and cylindrical shanks. For hard alloys, hardened steel and cast iron, drills with carbide inserts are more suitable. If the depth of the hole exceeds the dimeter by more than five times, special deep-drilling drills are used. To make center holes in stainless steel and other metals, center drills are used, as well as countersinks. Taps are used for tapping inside the drilled holes in metal constructions.

Stamping

Holes in stainless steel structures can also be made by cold-forming. The cold stamping method is a fast, high-precision, in-line process that greatly reduces the cost of finished stainless steel parts. However, stamping equipment is used only in large enterprises, as it requires a large capital investment.

Buy, price

Evek GmbH has a wide range of stainless steel products in stock that will satisfy any customer. The quality of the product is guaranteed by full compliance with the technological standards of production. Under the order we produce additional processing of products. The lead time is minimal. At wholesale purchases preferential discounts are provided.