Mounting errors of threaded connections and ways to eliminate them

Mounting errors of threaded connections and ways to eliminate them Major mistakes in the installation of threaded connections. Of all the types of connections that are used in mechanical engineering and plumbing, the most common are threaded. They help to create reliable fastening of parts,


and also have a lot of other advantages.

General information

Pluses of mounting option:

The main elements of fasteners are bolts, studs, nuts and screws. At least ball valves, mixers, American women and flexible hoses are attached to the steel thread. Sealing metal threads is usually done with flax fiber and red lead, but at the moment this method is no longer as popular as it used to be, since other materials and methods are much easier and more convenient to use.

Error overview

# 1

The first mistake to avoid at home for masters - other methods are not simpler and not more convenient. Is it another matter that it is not so easy to buy red lead at the moment than all kinds of investment pastes for joints.

In addition, it is extremely difficult to disassemble the connection on red lead, since it literally sticks tightly and it will take an effort to spin such a connection.

Linen fiber, as well as Unipack investment paste and FUM tape (made of fluoroplastic sealing material). The strangest ways of winding - first, the fibers are wound in an incomprehensible order, and then all the FUMs are wrapped with tape. We can talk about this for a long time, but there is only one lesson to be learned - do not do this ever! the use of FUM tape will be optimal. Packing threaded connections with its help does not require skills and is done without the use of sealants - the material was wound, as written in the instructions, and then the threads were tightened.

Naturally, the service life of such a connection is not too long, but it will not be difficult to do the same after 5 years.

The only problem with the method is that, due to the smoothness of the tape, the connection can indeed be easily mounted and dismantled, but this can be attributed to a disadvantage. It is very difficult to guess how many winding turns are required. After a while, under the influence of mechanical and vibration loads, the connections on the FUM tape will begin to weaken and leak. Such material is not suitable for the installation of taps and valves.

For this reason, it is better to still use flax and Unipake, so that the connection is durable and reliable.

Remember that winding should always be done in a clockwise direction, otherwise the flax will start to puff up while tightening the thread. Simply put, rewinding should be done exactly in the direction of the thread and not against it. You can use different methods for storing flax strands, it is only important that you learn to wind exactly as much material as required - no less and no more. The sequence of execution is as follows - they wound the strand on the thread, greased it with paste, twisted it - first by hand, and then we tighten it with the keys.

No. 2

The second mistake is winding flax counterclockwise. If you do this, then the material will begin to bristle during the tightening of the thread and it is unlikely that it will work to ensure tightness. It is for this reason that the winding should be exclusively clockwise.



The third mistake of winding on a threaded connection is that some people sometimes wind the thread under the connection using a union nut. Never do this! And it doesn't matter what we are talking about - about the union nut of the mixer, American or flexible liner. Such connections can be sealed using standard gaskets. Additional winding for the thread will be pointless and even harmful, since it can prevent the union nut from being tightened all the way so that it presses the gasket well.

If they are well clamped with a nut, then rewinding will be superfluous.

It is worth paying attention to what kind of notch on the American thread. Where the flax connection on the winding will pass, there are notches, and they are absent on the thread under the union nut. Crane axles also need to be sealed using standard gaskets and do not require reels, sealants and other additional materials for sealing.

No. 4

The fourth mistake is the use of flax, and not using investment pastes.

This can lead to the fact that the connection will only be tight for a short period, and without the paste, over time, the flax will start to rot. To avoid this, use special investment pastes, red lead, or, in extreme cases, oil paint.


Use only Unipack paste and flax for sealing, and the rest of the materials will not be suitable for novice plumbers. Moreover, even very experienced specialists pack the threads on the water supply using this method. Do not use winding threads under the union nuts of liners, mixers and American women, as well as any winding and sealants when installing the crane box.

( 1 grade, average 5 out of 5 )