Manual scanning: types, purpose, GOST

Get a drilling method hole, the walls of which would be perfectly even, it turns out not in every case, even with the use of quality drills and drills. In addition, the diameter of the hole may differ from the required by a few tenths of a millimeter. For the gaps to be perfect, you need a manual sweep. These metal-cutting tools are specially designed for finishing the holes after drilling and reaming operations. Let's look at what this tool represents, how it works, what it is needed for and how to apply it.

Characteristic

The sweep is a cutting tool for metal working. By treating the hole with this device, it is possible to increase its diameter, and also significantly improve the surface cleanliness and dimensional accuracy. Reamers are used for both finishing and pre-processing. There is a standard that governs manual scanning - GOST 7722-77. Manual tools are meant for processing holes with a diameter in the range from 3 to 60 mm (step - 1 mm).

With the help of these tools, you can obtain dimensions, the accuracy of which will correspond to the second and third class. With regard to surface cleanliness, it can be from Rz 10 to Rz 6.3. It is impossible to achieve such purity.

The principle of the sweep

Using a tool for processing holes, you can achieve high accuracy and surface quality - this is already mentioned above. Manual scanning works with small scales. Adjust the holes with this accuracy because the tool is equipped with several cutting edges. Thus, manual scanning - depending on the type - can have from 4 to 14 cutting edges. It is due to this that the smallest appetizers are removed.

The tool works as follows. The sweep needs to be inserted into the hole, then, if it's hand-held, put on a special wrenches and rotate the tool with it. The device will work not only with rotational movements, but also with simultaneous movement down or up the axis. The tool is able to remove thin layers of metal - from a few tenths to hundredths of a millimeter.

Process in this way, you can not only traditional cylindrical holes, but also conical. For this, a tapered sweep is used. There are several types of this cutting tool. In this article, we will examine each of these species.

What does the scan look like?

And the device looks like this. This is a cylindrical or conical rod, which on the working part has longitudinal grooves. The other part of it is smooth and can be equipped at the end with a square or conical shank.

The working side of the instrument is represented by several departments. The front part is conical and short. Then comes directly cutting, after - the guiding part and, finally, the rear working. This is what a sweep looks like. The tool, despite such a large number of working parts, directly cuts the metal only by the receiving or working part. A short back side is called calibrating. Between the cutting teeth grooves are formed. They are designed for chip removal during tool operation. Cutting edges are located along the whole circumference of the rod.

Classification

As is known, sweeps are designed for finish finishing of holes. In direct dependence on technological requirements, these tools produce holes in different tolerance ranges, from the fourth grade to the first. The accuracy of its operation depends on the design, as well as on the quality of the instrument. For different apertures different manual scanning is used - let's consider the main types.

As for the characteristics of the instrument, there is no one factor that plays a role here:

• Cutting Modes.
• The size of the allowance for deployment.
• Level of tool sharpening.
• Geometry of the cutting edge, as well as many other factors.

Sweeps are distinguished by the type of holes for which they are intended. The shape of the cutting teeth and the material being processed are also important.

In operation, the following are used to perform the main part of the locksmith operations: a cylindrical reamer, adjustable tools, tapered ones. Along with manual, there are also machine ones. These tools can be of different types. There are cylindrical, conical, with interchangeable teeth, with carbide cutting inserts.

A tapered drill includes a large group of tools - for tapered pins, for tapered threads, for the Morse cone, for metric cones. A cylindrical fine-grained tool is particularly widely used in plumbing.

Cylindrical

Such a scan is designed to process cylindrical holes. Manual sweep can be used both with a crank, and an electric drill at low speed. This tool can be executed in one piece or with the possibility of adjusting the working diameter.

Conical

This tool is designed to work with conical holes. They can also be used for traditional cylindrical holes.

Draft, intermediate, finishing

If you need to expand the size of the hole in a serious range, then you can not do without a set of tools of different purity. A conical sweep, like all the others, is divided into roughing, intermediate, and finishing.

The first tool is distinguished by the teeth, which are arranged along the entire line in steps. This tool works as follows. Cut the narrow chips with the cutting edge of each of the steps. In this case, if the hole was cylindrical, then after such treatment it becomes a stepped conical one. Intermediate scanning over metal can cut off shavings of much less thickness. The cutting part is distinguished by special channels for chip breaking. Finishing tools cut metal through the entire working surface. So, a cylindrical or conical hole of the right size is formed. As you can see, the principle of operation is quite simple.

Adjustable

A modern cutting tool of this type can be of various designs. On the market you can find expansion and sliding models. Both types work on the basis of one principle - when moving up or down, the diameter of the hole may decrease or increase. The sweep of these two types varies according to how the tightening is done, and also over the range of dimensions. So, in the expansion design there is an upper and lower nut. The size can be changed in the range from 0.25 to 3 millimeters. In sliding sweeps, the diameter changes due to the tightening of the screw. The latter causes a special ball to move in the body, which unclamps the cutting parts. The adjustable swivel is considered more accurate, and the maximum diameter can be increased from 0.15 to 0.5 millimeters.

As for the latter type, the tool is structurally similar to all other sweeps. It is a body made of inexpensive steels and plug-in cutting parts. Knives are made more often in the form of thin plates. As a material, tool steels are used. The plates are removed, can be sharpened and replaced. Such a sweep over the metal makes it possible to change the diameter of the hole by tenths and hundredths of a millimeter. Unlike whole, they are more economical. In case of wear, the knives can be easily replaced.

What do I need to know about the deployment of holes?

The process of hole boring is best performed using two classes of tools - roughing and finishing. The first are made more often from old and worn materials. Before unfolding the hole, its end part is grinded. This is done so that the scan can effectively work with each tooth. This is also true for cast iron parts. If you neglect such pre-processing, there is a risk of blunting the sweep. In the process of working with a scan, it's better not to hurry once again. Feed must be carried out evenly. The slower the tool will be fed into the hole, the better the final result. The deployment process does not involve working at high speeds, as in the case of a drill. Experienced locksmiths recommend to postpone the electric drill, and instead take a wig. In this case, the control of the process will be much higher.