What is measured length? Measured, unmeasured and multiple lengths of pipes

Unmeasured reinforcement is a bundle of hot-rolled steel uneven in length, the shape of the rods in which has special transverse ribs. Like the dimensional type of reinforcement, it is used in various fields of construction.

1

Steel bars of non-dimensional reinforcement are made by hot rolling from various grades of low-alloy and carbon steels. Production is regulated by GOST 52544 standards and technical conditions. According to its characteristics, non-gauge fittings are no different from measuring rods, the only difference- length of the product. Gauge fittings have a standard length of 11.7 meters, while non-gauge rolled metal can be from 1.5 to 12 meters long, depending on the scope of application.

Unmeasured fittings

Some factories have the ability to produce fittings of unmeasured length, which exceeds 12 meters. The production of this type of fittings is carried out in accordance with various classes (At600, At800, At1200). In addition, non-dimensional reinforcement may differ by profile type. Today, factories offer the following types:

• smooth profile (AI marking);
• periodic profile (marking AII or AVI).

The diameter of reinforcement of unmeasured length can vary between 8-32 millimeters. Weight of one linear meter class 12 A500C is 0.88 kilograms. Additional marking according to GOST may contain information about the steel grade, corrosion resistance and other characteristics. High-quality rolled products of measured and unmeasured types must have a clear structure and profile without signs of deformation (cracks, breaks, chips). The price of non-dimensional fittings is significantly lower than analogues standard length, which makes it in demand in various fields of construction.

2

Since this type of reinforcement belongs to the class of rolled metal products, the main area of ​​application is the creation of reliable reinforced concrete structures. Unlike measured reinforcement, non-measured reinforcement cannot provide maximum reliability in adhesion to concrete, so experts recommend using non-measured rods primarily as the main material for creating supports.

Application of unmeasured fittings

This type is most often used in low-rise construction, during the construction of foundations. belt type, as a reinforcing element in the construction of domestic buildings, when laying steel mesh, as well as for strengthening walls and concrete floors. Among the main advantages of long products are:

• The presence of transverse profile ribs. This allows you to create a more reliable adhesion to the concrete matrix; in addition, this type of profile increases wear resistance characteristics.
• Technological production. This type of long products is made from various grades of carbon steel according to special technology strengthening of the metal, which significantly increases its strength.
• Low cost. Due to the fact that unmeasured rolled products 12 are most often made from more simple types steel, its final cost is much lower than gauge fittings.
• Good weldability and high corrosion resistance. In addition, this metal has a special degree of viscosity, which allows it to be used in the construction of foundations.

3

Many experts agree that using iron rods of irregular length 12 as the main material when constructing foundations and other reinforced concrete structures is not always advisable due to the special properties of the metal and the risk of overuse of material. However, if you carry out correct and competent calculations, you can avoid overspending and use the material to the maximum.

Use of reinforcement in construction

The main feature of non-dimensional reinforcement 12 during construction is the ability to reduce overlap when creating iron frame, which cannot be done when working with standard length rods.

Considering the lower cost of such material, it makes sense to use non-dimensional reinforcement when creating small structures and supports. For large buildings and objects, it is recommended to take measuring reinforcement, as it can withstand heavy loads and adheres better to the concrete matrix. In addition, rolled products have a clearer structure and a different type of profile, which provides certain advantages.

It is important to understand that reinforcement of unmeasured length is a very popular material for construction; when purchasing rolled steel 12, you need to ensure the quality of the metal and full compliance with GOST 52544 and various standards technical specifications. The reinforcement is supplied in bundles, which must be properly packaged, and the packaging must be accurately marked with all the characteristics, including weldability (C) and corrosion protection (K) indicators.

Jackson 14-02-2007 01:56

Can you recommend something that is budget friendly and actually works?

yevogre 14-02-2007 12:19

quote: Originally posted by Jackson:
I took a Belarusian pipe with a variable magnification of 20x50, for work at the shooting range, the sellers guaranteed that at 200m I would see holes on the target from 7.62 without problems, it turned out to be about 60m, and even then with difficulty (though the weather was cloudy).
Can you recommend something that is budget friendly and actually works?

shtift1 14-02-2007 14:54

IMHO ZRT457M, around 3 thousand (100USD), quite functional up to 200 m, at 300 at light background visible from 7.62.

Jackson 14-02-2007 21:17

Thank you for your comments

stg400 15-02-2007 21:28

The question regarding pipes is very complex, you need to look at it first
to any. And the advice is this - DO NOT BUY A BUDGET PIPE WITH A VARIABLE
IN MULTIPLICITY. They don’t really know how to deal with constant work.

or won't it help?

yevogre 15-02-2007 21:37

I have an idea who would rate the “level of delusion”...

Cut out a “diaphragm” from cardboard
and stick it on the lens. To improve "sharpness".
The aperture will certainly drop. But don't throw away the pipe...

or won't it help?

This is a way out if the main “instigator” of the loss of permission
is the lens. And this is 90% wrong. Lens with focus ~450 mm
We've already learned to count. And here it begins.....
The wrapper is a thick piece of glass in the path of the beam that magnifies
chromaticism in black. But that's not all. The most important thing is standard
eyepiece, the diagram of which has not been recalculated “as unnecessary”
decades. In this case, its focus should be around 10 mm, and when
In standard schemes, this resolution is “lowered” by an order of magnitude. About
I won’t even mention the variable multiplicity of such “masterpieces”.

Serega,Alaska 16-02-2007 08:20

quote: Originally posted by yevogre:

The question regarding pipes is very complex, you need to look at it first
to any. And the advice is this - DO NOT BUY A BUDGET PIPE WITH A VARIABLE
IN MULTIPLICITY. They don’t really know how to deal with constant work.
Choose an increase for yourself - and try, try....

How right is this...
From a positive experience, I bought a 20x50 constant from a little-known science manufacturer NCSTAR on eBay. It’s military-style, everything is covered in green rubber. Naturally, the pupil is 2.5 mm, you can’t spoil it. But it’s small, light, with its own tabletop tripod, and naturally the holes are visible , believe it or not. At 100 m there are no questions, but to see it at 200 m you still need more light, it only works until early twilight. The price tag on eBay is $25 with delivery. I won’t say that the issue has been resolved forever, but at the very least it works from a steel concrete table at a shooting range. At the same time, use in the field (from the hood, for example, in a good field) is absolutely excluded, everything trembles until a complete loss of sharpness.

Only a constant in the budget (they are not so easy to find, by the way)!

Dr. Watson 16-02-2007 09:41

Burris has a nice 20x trumpet.

stg400 16-02-2007 19:42

quote: Originally posted by Serega,Alaska:

manufacturer NCSTAR, little known to science.

stg400 19-02-2007 07:58

the “aperture” on the lens didn’t help..
throw away the pipe...

konsta 19-02-2007 23:46

Give it to children. At least there will be joy left over.

Serega,Alaska 20-02-2007 02:10

quote: Originally posted by Serega, AK:

manufacturer NCSTAR, little known to science.

quote: Originally posted by stg400:

manufacturer of optics under government order for the carry handle of the little-known M16 rifle...
although now there is no longer that government order..

Or maybe it wasn’t? So to speak, was there a government order?

The thing is that manufacturers are deservedly proud of such things and post information about this on all real and virtual fences. Here is AIMPOINT, for example. His website is full of camouflage, SWAT, police and other military elements. In the red corner - Aimpoint Secures New Contract From U.S. Military - http://www.aimpoint.com/o.o.i.s/90 about how they have already sold 500,000 sights to the army and contracted for another 163,000. And, really, go buy their products. Firstly, there is very little of it on the wide market; a search on eBay shows this clearly. (I have an auto search on AIMPOINT on eBay, it’s good if they put at least something up every two weeks. And the 9000L, which I’m interested in, has never come across.) Secondly, the AIMPONT that serious people have dealers - noticeably more expensive than competitors, including quite decent ones (for example, Nikon RED DOT Monarch - $350-450 for AIMPOINT red dot - this is a kind of record in this class, as is the 10-year warranty. All this is real). status as a military contractor with a reputation.

But NcSTAR does not proclaim anything like that. Rustem says it’s been 10 years since 1997, i.e. Not so much ancient history, so that the state order for their sights for the M16 should be mentioned in capital letters, if there ever was one. Yes, they do something like that for the M16, but which owner of a real M16 buys this for $50? And tons of everything from NcSTAR on eBay for pennies, including products for airborne replicas of the M-16, AR-15, etc. But serious dealers, as a rule, do not keep it.

I'm afraid someone misinformed you. And I, as I mentioned NcSTAR in a positive sense for the super-budget constant 20x50, I simply don’t want to attribute more to them than they deserve. Someone else will warm up, God forbid...

Thank you for your attention,
Serega, AK

stg400 20-02-2007 02:31

and there is also a bullshit airline PanAmerican... there are unknown companies Polaroid and Korel... their shares have long been withdrawn from trading on the stock exchanges...

so did NcStar.. made some kind of glass on the carry handle.. now the M16 with them is not in service.. all are flat top receivers and they have ACOG from another company..

Nowadays, those who want to purchase high-quality modern binoculars have a lot of options. The choice of a wide variety of equipment from global manufacturers is unusually large, including in online stores. But it is best to choose the one that is right for you. technical parameters and at the same time will suit the price.

This device is quite technically complex, and it is sometimes difficult for the average consumer to understand its characteristics. For example, what does “30x60 binoculars” mean? Let's try to find out.

What types of binoculars are there?

When starting to make a choice, decide what approximation is enough for you to observe, will you use the device not only in bright light, but also in the twilight, will you be satisfied with a lightweight option with which long-term observation is possible? For the same 30x60 binoculars, reviews can be very different depending on the needs of the owner.

Therefore, it is so important to decide why exactly you are buying this device and under what conditions you are going to use it.

Binoculars can be theatrical and military, naval or night vision, as well as small compact ones - for those present at the stadium during competitions. Or, on the contrary, large ones, intended for observations by astronomers. Each variety has its own characteristics. Sometimes they differ quite significantly. To do good choice, let's get acquainted with the main ones.

What is multiplicity?

This is one of the the most important characteristics an instrument such as binoculars. Multiplicity tells us about the ability to increase the environment. If, for example, its indicator is 8, then at the maximum approximation you will view the observed object at a distance that is 8 times less than the one at which it actually is.

Trying to buy a device with the highest possible magnification ratio is unreasonable. This indicator should be related to the circumstances and place of use of the binoculars. For observations in field conditions It is customary to use equipment with magnification numbers from 6 to 8. Magnification of binoculars of 8-10 times is the maximum at which you can observe handheld. If it is higher, jitter, which is also amplified by optics, will interfere.

Binoculars with significant magnification (from 15-20x) are used in conjunction with a tripod, on which they are mounted using a special adapter or adapter. The large weight and dimensions are not suitable for long-term wearing and in most cases are not needed, especially when the view is obstructed by many obstacles.

Models with variable magnification (pancratic) are produced. The degree of magnification in them is changed manually, like photographic lenses. But due to increased complexity devices are more expensive.

What does “30x60 binoculars” mean, or Let’s talk about lens diameter

The marking of any binocular contains the size of the diameter of the front lens of its objective, which is given immediately after the magnification index. For example, what does “30x60 binoculars” mean? These numbers are deciphered as follows: 30x is the magnification factor, 60 is the size of the lens diameter in mm.

The quality of the resulting image depends on the diameter of the lens. In addition, it determines the flow of light from binoculars - the larger the diameter, the wider it is. Universal for hiking conditions Binoculars marked 6x30, 7x35 or, in extreme cases, 8x42 are considered. If you plan to conduct observations in nature during the day, and you will be looking at fairly distant objects, take a device with a magnification of 8 or 10 times and a lens with a diameter of 30 to 50 mm. But at dusk they are not very effective due to less light entering the lenses.

The best binoculars for spectators at sporting events are small (pocket size) with parameters around 8x24, they are good for general shots.

If there is not enough light

In conditions poor lighting(at dusk or dawn) you should either prefer the device large diameter lenses, or sacrifice magnification. The optimal ratio may be 7x50 or 7x42.

A separate group is the so-called night binoculars - active and passive. Passive lenses are equipped with a multi-layer coating that eliminates glare. They are used in the presence of minimal lighting (for example, moonlight). Active devices also work in complete darkness, as they use infrared radiation. Their disadvantage is their dependence on the power source.

Those who like to study space objects (for example, look at the topography of the lunar surface) need binoculars that are powerful enough, with a magnification of at least 20x. For a more detailed acquaintance with the night sky, it is better for an amateur astronomer to take a telescope, which in this case cannot be replaced even by the best binoculars.

What is viewing angle?

The viewing angle (or its field) is another important characteristic. This value in degrees indicates the width of coverage. This parameter is inversely dependent on magnification - powerful binoculars have a small “angle of view”.

Binoculars with a wide viewing angle are called wide-angle (or wide-field). They are convenient to take to the mountains to better navigate in space.

Often this indicator is expressed not as a graduated angle, but as the width of a segment or space that can be viewed at a standard range of 1000 m.

Other binocular characteristics

The exit pupil diameter is the quotient of the entrance pupil diameter divided by the magnification value. That is, for binoculars marked 6x30 this figure is 5. The optimal number in this case is about 7 mm (the size of the human pupil).

What does "30x60 binoculars" mean in this case? The fact that the exit pupil size with this marking is 2. Such binoculars are suitable for not too long observation in good lighting, then the eyes are at risk of fatigue and overstrain. If the illumination leaves much to be desired, or long-term observation is required, this indicator should be at least 5, and preferably 7 or more.

Another parameter - aperture "controls" the brightness of the image. It is directly dependent on the diameter of the exit pupil. The abstract number that characterizes it is equal to the square of its diameter. In low light conditions, it is advisable to have this indicator at least 25.

The next concept is focus. Being central, she - universal remedy quick focusing. Its regulator is located near the hinge connecting the pipes. For glasses wearers, it is advisable to have binoculars with diopter adjustment.

What else is important

Others, not so much global characteristics binoculars, however, play a significant role in its selection. Depth of field is the length of the segment to the object of observation, on which it is not necessary to change the adjusted focus. The higher the magnification of the device, the lower it is.

Binoculars have the property of stereoscopicity (binocularity) characteristic of the human eye, which makes it possible to observe objects in volume and perspective. This is its advantage over a monocular or telescope. But this quality, useful in the field, interferes in other cases. Therefore, for example, in it is reduced to a minimum.

According to the optics systems, binoculars are lens (theater, Galilean) and prism (or field). The former have good aperture, direct image, low magnification and a narrow field of view. Secondly, prisms are used that turn the inverted image obtained from the lens into a familiar one. This reduces the length of the binoculars and increases the viewing angle.

The ability of a device to transmit rays of light, expressed as a fraction, is called. For example, with a loss of 40% of light, this coefficient is 0.6. Its maximum value is one.

What type of binocular body is there?

Its main advantage is strength. Shockproof qualities are ensured by the rubber coating of the case, which also ensures reliability when held in the hands and moisture resistance in wet weather.

Modern waterproof binoculars are so sealed that they can remain under water for some time at a depth of up to 5 meters without harm. The lenses protect against fogging by filling the space between them with nitrogen. These qualities are important for tourists, hunters, and naturalists. Binoculars with a rangefinder are useful for researchers, and a device with a dim matte surface is useful for those who like to watch animals.

Certain non-standard functions of individual devices, such as image stabilizer or a built-in compass, significantly increase the cost of binoculars and are welcome only when necessary. Decide for yourself whether you really need, for example, binoculars with a rangefinder, and whether you are willing to overpay for this option.

The main materials for manufacturing are various grades of carbon and alloy steel, aluminum and its alloys, brass and copper. Depending on the main component, there are several types of metal circles. These varieties and the percentage of components in their composition are shown in Table 1.

Technical documentation

• GOST 2590–2006 “High-rolled hot-rolled round steel products. Assortment"
• GOST 7417–75 “Calibrated round steel. Assortment"
• GOST 535–2005 “Rolled section and shaped products made of carbon steel of ordinary quality. General technical conditions"
• GOST 5632–72 “High-alloy steels and corrosion-resistant, heat-resistant and heat-resistant alloys. Stamps"
• GOST 21488–97 “Extruded rods from aluminum and aluminum alloys. Technical specifications"
• GOST 4784–97 “Aluminium and wrought aluminum alloys. Stamps"
• GOST 1131-76 “Deformable aluminum alloys in ingots. Technical specifications"
• GOST 2060–2006 “Brass rods. Technical specifications"
• GOST 15527–2004 “Copper-zinc (brass) alloys processed by pressure. Stamps"
• GOST 1535–2006 “Copper rods. Technical specifications"

One of the types of products of the metal rolling industry is pipes of a wide range. Modern construction Russia cannot do without the use of this unique material. Steel products have high strength characteristics, they are durable and reliable.

Most meaningful view The application of steel pipes is the design of transportation systems: oil, water and gas. In addition to the actual pipeline work, metal pipes are used to insulate communications.

Purchase metal pipes should only be based on data on the temperature and humidity conditions under which it will be operated.

As for the cross-sectional shape, the most common one is round. When fulfilling your order, we work with specific parameters and can produce rolled pipes with the required diameter. We are also ready to supply pipes of square, rectangular and other sections. It all depends on the specific production needs.

Steel pipes are made from various steel grades: 10, 20, 35, 45, 09G2S, 10G2, 20Х, 40Х, 30ХГСА, 20Х2Н4А, etc.

Steel pipes are divided by type into:

• Electric-welded steel pipes - Non-galvanized and galvanized welded steel pipes used for water pipelines, gas pipelines, heating systems and structural parts.
• Seamless steel pipes - Steel pipes, not having weld or other connection. They are made by rolling, forging, pressing or drawing.

Steel pipes are divided by class into:

• Water-gas pipes (WGP): GOST 3262 and Galvanized water-gas pipes - GOST 3262
• Electric-welded pipes: GOST 10705, 10704 and Galvanized electric-welded pipes GOST 10705, 10704
• Large diameter pipes: Main pipes GOST 20295 and Electrical pipes GOST 10706
• Seamless pipes: Hot-deformed GOST 8731, 8732 and Cold-deformed GOST 8731, 8734

STEEL WATER AND GAS PIPES

The length of the pipe is made from 4 to 12 m:

a) measured or multiple measured length with an allowance for each cut of 5 mm and a longitudinal deviation over the entire length plus 10 mm;

b) of unmeasured length.

By agreement between the manufacturer and the consumer, up to 5% of pipes with a length of 1.5 to 4 m are allowed in a batch of unmeasured pipes.

The length of the pipe is made from 4 to 12 m

Dimensions, mm