Fitting and Tubing

FITTINGS AND TUBING GUIDE

Choosing the right fittings and tubing is almost equally important as choosing any other component in a liquid cooling loop and usually quite confusing to beginners. First, you must decide what do you prefer because there are several sizes and types of fittings and tubing which make this subject quite broad. It’s important that you know all the possible choices of fittings because they can have a big visual impact on the finished build.

1. HOW TO READ TUBE AND FITTING MEASUREMENTS?

Metric and imperial measurements of the fittings provide inner and outer diameter.

Metric measurements

The liquid cooling market provides three diameters of soft tubing that are the most common. Tubes are marked with ID and OD which stand for „Inner Diameter“ and „Outer Diameter“. There are two ways to mark the fittings, one is using metric millimeters (mm) and the other is using imperial inches (“). These three most common tubes are marked with numbers such as:

10/13mm or 3/8”-1/2″ ,
10/16mm or 3/8”-5/8”,
12/16mm or 7/16”-5/8”,

Some fittings on the market use only a number to mark the size without using the unit next to it. Since the imperial way of marking the fittings is getting less and less popular these days, its really easy to differentiate the fittings by using just 12, 14, and 16 as the size differentiators.

There might be some other tubing and fitting sizes available on the market, but we will not cover all of them. The most important thing is to pick parts from well-known manufacturers to avoid incompatibilities and unpleasant experiences with water cooling just because someone wanted to save a few bucks on the tubes on fittings. Water cooling components like fittings and tubing are best not bought from the flea market. The tubes you use must exactly match the ID and OD parameters of the fitting you are using,  because if leaks occur, your components may be harmed.

2. SELECT THE FITTINGS TYPE

While in the early days we had simple barb fittings, nowadays the market has narrowed down to only compression type fittings. While barb fittings are still available for workstation purposes and applications where the aesthetics are not a key point, the market is dominated by compression type fittings. The compression fittings themselves are divide into two major categories which are, Soft Tubing Compression and Hard Tubing Compression fittings, or for short STC and HDC.

Soft Tubing Compression Fittings

These compression fittings are marked with two numbers that state the inner diameter (ID) and outer diameter (OD) of the tubing that is compatible with the fitting.  Both these number markings of the tubing must match with the fitting. As for the old-school barb fittings, there is only one number present, the OD of the barb, which has to match with the ID of the tubing that will be used. Thankfully, both the tubing and fitting types are standardized, so you are able to choose from 10/13, 10/16, and 12/16 sizes of soft tubing compression fittings.

A soft tubing compression fitting (STC) consists of two parts, the main part is the base and it’s very similar to the standard barb fitting, but it has an additional thread. The other part is the locking ring which screws on to the base of the fitting and it prevents the tubing from slipping off the barb. There is a point where the locking ring compresses and grips the tube, making an airtight seal, hence the name „compression fitting“.

Unlike the barbed fitting, where the tube just goes over it, the locking ring big and visible part of the compression fitting, leaving a lot of room for manufacturers to play around with the aesthetics. The locking ring can be formed and painted in many exciting ways and that is why builders are favoring them for their water cooling systems.

Compression fittings require a bit more access because the user must tighten the locking ring to ensure a leak-free connection. A simple fitting tightening can be a time-consuming process, especially if mATX or mITX cases are used and you just can’t get a good grip on the locking ring. For reasons like this, it is recommended to combine quality and compatibility-tested tubing and fittings, because even a few microns of misalignment in the thickness of the tubing can make the tightening of the locking ring hard or even impossible.

Hard Tubing Compression Fittings

Fittings for hard tubing are marked with only one number, which stands for the OD (Outer Diameter) of the tube it can accommodate. A hard tubing compression fitting (HDC) consists of more parts, but the two most important are the base and the locking ring. The hard tubing compression fitting usually also has two more o-rings. One is nested inside the base of the fitting, while the other one sits between the base and the locking ring. The most common sizes for hard tubing compression fittings are for 12mm, 14mm and 16mm tubes.

When the tubing is installed, the locking ring is pushing down on the additional o-ring and it prevents the tubing from slipping out of the base. There is a point where the locking ring compresses the o-ring which grips the tube, making an airtight seal, and this is why these are also „compression fittings“.

Some manufacturers use more than one o-ring in the base of the fitting or use a single special-shaped o-ring to grip the tubing, but in the end, they all serve the same purpose. To compress an o-ring which prevents the tube from popping out of the base of the fitting.

Hard Tubing Push-In Fittings

Fittings for hard tubing can also be a simple push-in type. Hard tubing push-in (HDP) fittings have two fixed o-rings inside – you just have to push the tube into the fitting and airtight seal is made. These are engineered mainly for captive tubing, as they are intended to be used between two GPU water blocks, or from a GPU to the distro plate or similar cases where the tubing is not able to move.

3. SELECT THE TUBING TYPE

It is crucial that you match the desired tubing dimensions with the fitting dimensions and this requires some planning ahead. Usually, users first choose the type and size of fittings and then pick the matching tubing or vice versa –  the less common way, they chose the tubing first and then the fittings.

We separate tubing types into two main branches, just like the fittings. Soft tubing and hard tubing. These two types of tubes use entirely different types of fittings which are not cross-compatible. We will also go over the basics of the tubing because it will be easier for you to distinguish them when you will be choosing between the two.

Soft tubing

Soft tubing is often made out of neoprene, rubber, silicone, PVC, or other special compounds that are specifically made to be compatible with PC liquid cooling. You can choose see-through – clear tubing, colored – non-transparent tubing, and UV reactive tubing. You cannot choose any tubing from the local market for water cooling. Well, ideally, you can, but no one can guarantee if some manufacturing residues will impact the coolant stability, or you will spring a leak because of size tolerance issues.

Lately, colored tubing is not popular and the majority of the users are choosing transparent tubing to be able to display the coolant color, or just go for all black tubing. Here we can mention two market-proven options that are the EK-DuraClear transparent and EK-Tube ZMT soft tubing which are both available in multiple dimensions.

Tubing for water cooling is specially made to withstand long periods of time without any discoloration, deformation, or degradation. If aesthetics is one of your main goals with liquid cooling, and you plan to use colored coolants, make sure that you choose a quality tubing that will stay crystal clear as long as it can. Low-grade cheap tubing can lose its transparency in a matter of days and it often becomes yellow.

Liquid cooling tubes need to be soft enough to allow tight bends inside of the computer case and hard enough to withstand collapsing – kinking. Soft tubing with thicker walls like the 10/16 will be more resistant to kinks under tight bends.

Hard tubing

Moving onto the other type of tubing, called hard tubing. Unlike the soft tubing, that is made of some sort of synthetic rubber or plastic, hard tubes can be made from a broad spectrum of materials. The most common hard tubes for liquid cooling are acrylic (plexiglass) or PETG (polyethylene terephthalate). They are cheap, easy to come by, and can be shaped and bent in every household. There are tools available which can make acrylic and PETG bending really easy, but we will not elaborate on that subject now, we will leave that for another article as hard tube bending is considered to be a more advanced loop building method.

The other, less common hard tubes can be made out of copper, brass, borosilicate glass and nowadays even carbon tubes are coming into fashion. The potential problem with these materials is that bending them is not possible or bending requires special tools. We say the „potential problem“ because skilled and more advanced users actually prefer these luxurious materials because the loop can still be connected just by using more adapter fittings and more joints.

Hard tubing can offer a few things soft one can never do, and that’s the luxury and exclusivity we have just mentioned. Hard tubes offer a clean and well-organized look. Brass and copper tubes can be nickel-plated to achieve a more sophisticated and aesthetically pleasing look.

The existence of pre-bent tubes and rising popularity distro plates, building with hard tubes have never been easier. As a matter of fact, a lot of the newcomers to custom loop liquid cooling have built their first loop using distro plates and hard tubing. We are more than happy to give you a hot tip that EK is working on bringing pre-bent tubes to the product portfolio.  We also promise that we will cover distro plates in more detail with one of our upcoming blog posts.

WHAT IS G1/4″?

Regarding the fittings, there is one more detail you need to know. Almost all of the fittings nowadays use the G1/4“ thread (12.9mm wide) and this is the industry standard for all mainstream custom loop liquid cooling manufacturers. In case you are tumbling through server solutions or some older water cooling gear, you might stumble upon  G1/8“ (9mm wide) or G3/8“ (16.5mm wide) threads. But like we said, the G1/4“ is the norm and the other sizes have become very rare. So the G1/4″ label is just the thread size label, which makes sure that your liquid cooling products are compatible with each other.

15

It is very important to know that choosing thicker tubes and bigger fittings will not result in greater flow. As we said, the great majority of the fittings and connections on water cooling parts use the G1/4“ thread. The cross-section of the flow is limited by the outer dimension of the fitting, and the inner diameter of the fitting with a G1/4“ thread usually cannot exceed 9-10mm.

Meaning, even if you choose thicker tubes, at the end of the tube the fitting will narrow the flow diameter down to 9-10mm. Water blocks and other parts can be restrictive also, so by using the thicker tube, before and after the water block, you will have no benefits in flow rate. If a greater flow rate is required, a more powerful pump is to be chosen.

Conclusion

We would wrap up this article at this moment, although we are certain that we didn’t cover all the small details. As we said at the start, this subject is very broad, there are many choices, but we hope that we managed to cover the basics. In one of the future articles, we will cover the subject of angled adapters and other special connectors, such as T-Splitters and Ball Valves!

We would most certainly like to invite you to comment on this article, whether you see it on the EK blog page or on the EK Water Blocks Facebook page. Feel free to fill us in if you feel that we left out some details.

Until next time, stay cool!

Source: https://www.ekwb.com/blog/fittings-and-tubing-guide/#top

Abrasive merk 3M, Norton, Resibon, Ultra dll

From Wikipedia, the free encyclopedia Jump to navigationJump to searchFor the Puddle of Mudd album, see Abrasive (album).

An abrasive is a material, often a mineral, that is used to shape or finish a workpiece through rubbing[1] which leads to part of the workpiece being worn away by friction. While finishing a material often means polishing it to gain a smooth, reflective surface, the process can also involve roughening as in satin, matte or beaded finishes. In short, the ceramics which are used to cut, grind and polish other softer materials are known as abrasives.

Abrasives are extremely commonplace and are used very extensively in a wide variety of industrial, domestic, and technological applications. This gives rise to a large variation in the physical and chemical composition of abrasives as well as the shape of the abrasive. Some common uses for abrasives include grinding, polishing, buffing, honing, cutting, drilling, sharpening, lapping, and sanding (see abrasive machining). (For simplicity, “mineral” in this article will be used loosely to refer to both minerals and mineral-like substances whether man-made or not.)

Files are not abrasives; they remove material not by scratching or rubbing, but by the cutting action of sharp teeth which have been cut into the surface of the file, very much like those of a saw. However, diamond files are a form of coated abrasive (as they are metal rods coated with diamond powder).

Contents

  • 1Mechanics of abrasion
  • 2Abrasive minerals
  • 3Manufactured abrasives
    • 3.1Bonded abrasives
    • 3.2Coated abrasives
    • 3.3Other abrasives and their uses
  • 4Choice of abrasive
  • 5Other instances of abrasion
  • 6See also
  • 7References
  • 8External links

Mechanics of abrasion[edit]

Main article: Abrasion (mechanical)

Abrasives generally rely upon a difference in hardness between the abrasive and the material being worked upon, the abrasive being the harder of the two substances. However, is not necessary as any two solid materials that repeatedly rub against each other will tend to wear each other away; examples include, softer shoe soles wearing away wooden or stone steps over decades or centuries or glaciers abrading stone valleys.

Typically, materials used as abrasives are either hard minerals (rated at 7 or above on Mohs scale of mineral hardness) or are synthetic stones, some of which may be chemically and physically identical to naturally occurring minerals but which cannot be called minerals as they did not arise naturally. (While useful for comparative purposes, the Mohs scale is of limited value to materials engineers as it is an arbitrary, ordinal, irregular scale.) Diamond, a common abrasive, for instance occurs both naturally and is industrially produced, as is corundum which occurs naturally but which is nowadays more commonly manufactured from bauxite.[2] However, even softer minerals like calcium carbonate are used as abrasives, such as “polishing agents” in toothpaste.Grit size ranging from 2 mm (the large grain) (about F 10 using FEPA standards) to about 40 micrometres (about F 240 or P 360).

These minerals are either crushed or are already of a sufficiently small size (anywhere from macroscopic grains as large as about 2 mm to microscopic grains about 0.001 mm in diameter) to permit their use as an abrasive. These grains, commonly called grit, have rough edges, often terminating in points which will decrease the surface area in contact and increase the localised contact pressure. The abrasive and the material to be worked are brought into contact while in relative motion to each other. Force applied through the grains causes fragments of the worked material to break away, while simultaneously smoothing the abrasive grain and/or causing the grain to work loose from the rest of the abrasive.

Some factors which will affect how quickly a substance is abraded include:

  • Difference in hardness between the two substances: a much harder abrasive will cut faster and deeper
  • Grain size (grit size): larger grains will cut faster as they also cut deeper
  • Adhesion between grains, between grains and backing, between grains and matrix: determines how quickly grains are lost from the abrasive and how soon fresh grains, if present, are exposed
  • Contact force: more force will cause faster abrasion
  • Loading: worn abrasive and cast off work material tends to fill spaces between abrasive grains so reducing cutting efficiency while increasing friction
  • Use of lubricant/coolant/metalworking fluid: Can carry away swarf (preventing loading), transport heat (which may affect the physical properties of the workpiece or the abrasive), decrease friction (with the substrate or matrix), suspend worn work material and abrasives allowing for a finer finish, conduct stress to the workpiece.

The material allowing confused to absorb

Abrasive minerals[edit]

Diamond powder paste

Abrasives may be classified as either natural or synthetic. When discussing sharpening stones, natural stones have long been considered superior but advances in material technology are seeing this distinction become less distinct. Many synthetic abrasives are effectively identical to a natural mineral, differing only in that the synthetic mineral has been manufactured rather than mined. Impurities in the natural mineral may make it less effective.

Some naturally occurring abrasives are:

  • Calcite (calcium carbonate)
  • Emery (impure corundum)
  • Diamond dust (synthetic diamonds are used extensively)
  • Novaculite
  • Pumice
  • Iron(III) oxide
  • Sand
  • Corundum
  • Garnet
  • Sandstone
  • Rotten stone (Tripoli)
  • Powdered feldspar
  • Staurolite

Some abrasive minerals (such as zirconia alumina) occur naturally but are sufficiently rare or sufficiently more difficult or costly to obtain such that a synthetic stone is used industrially. These and other artificial abrasives include:

  • Borazon (cubic boron nitride or CBN)
  • Ceramic
  • Ceramic aluminium oxide
  • Ceramic iron oxide
  • Corundum (alumina or aluminium oxide)
  • Dry ice
  • Glass powder
  • Steel abrasive
  • Silicon carbide (carborundum)
  • Zirconia alumina
  • Boron carbide
  • Slags

Manufactured abrasives[edit]

Abrasives are shaped for various purposes. Natural abrasives are often sold as dressed stones, usually in the form of a rectangular block. Both natural and synthetic abrasives are commonly available in a wide variety of shapes, often coming as bonded or coated abrasives, including blocks, belts, discs, wheels, sheets, rods and loose grains.

Bonded abrasives[edit]

Assorted grinding wheels as examples of bonded abrasives.A grinding wheel with a reservoir to hold water as a lubricant and coolant.

bonded abrasive is composed of an abrasive material contained within a matrix, although very fine aluminium oxide abrasive may comprise sintered material. This matrix is called a binder and is often a clay, a resin, a glass or a rubber. This mixture of binder and abrasive is typically shaped into blocks, sticks, or wheels. The most common abrasive used is aluminium oxide. Also common are silicon carbide, tungsten carbide and garnet. Artificial sharpening stones are often a bonded abrasive and are readily available as a two sided block, each side being a different grade of grit.

Grinding wheels are cylinders that are rotated at high speed. While once worked with a foot pedal or hand crank, the introduction of electric motors has made it necessary to construct the wheel to withstand greater radial stress to prevent the wheel flying apart as it spins. Similar issues arise with cutting wheels, which are often structurally reinforced with impregnated fibres. High relative speed between abrasive and workpiece often makes necessary the use of a lubricant of some kind. Traditionally, they were called coolants as they were used to prevent frictional heat build up which could damage the workpiece (such as ruining the temper of a blade). Some research suggests that the heat transport property of a lubricant is less important when dealing with metals as the metal will quickly conduct heat from the work surface. More important are their effects upon lessening tensile stresses while increasing some compressive stresses and reducing “thermal and mechanical stresses during chip formation”.[3]

Various shapes are also used as heads on rotary tools used in precision work, such as scale modelling.

Bonded abrasives need to be trued and dressed after they are used. Dressing is the cleaning of the waste material (swarf and loose abrasive) from the surface and exposing fresh grit. Depending upon the abrasive and how it was used, dressing may involve the abrasive being simply placed under running water and brushed with a stiff brush for a soft stone or the abrasive being ground against another abrasive, such as aluminium oxide used to dress a grinding wheel.

Truing is restoring the abrasive to its original surface shape. Wheels and stones tend to wear unevenly, leaving the cutting surface no longer flat (said to be “dished out” if it is meant to be a flat stone) or no longer the same diameter across the cutting face. This will lead to uneven abrasion and other difficulties.

Coated abrasives[edit]

A German Klingspor sandpaper showing its backing and FEPA grit size.Main article: Coated abrasive

coated abrasive comprises an abrasive fixed to a backing material such as paper, cloth, rubber, resin, polyester or even metal, many of which are flexible. Sandpaper is a very common coated abrasive. Coated abrasives are most commonly the same minerals as are used for bonded abrasives. A bonding agent (often some sort of adhesive or resin) is applied to the backing to provide a flat surface to which the grit is then subsequently adhered. A woven backing may also use a filler agent (again, often a resin) to provide additional resilience.

Coated abrasives may be shaped for use in rotary and orbital sanders, for wrapping around sanding blocks, as handpads, as closed loops for use on belt grinders, as striking surfaces on matchboxes, on diamond plates and diamond steels. Diamond tools, though for cutting, are often abrasive in nature.

Other abrasives and their uses[edit]

Here the abrasiveness of toothpaste is detailed by its Relative Dentin Abrasivity (RDA)

Sand, glass beads, metal pellets copper slag and dry ice may all be used for a process called sandblasting (or similar, such as the use of glass beads which is “bead blasting”). Dry ice will sublimate leaving behind no residual abrasive.

Cutting compound used on automotive paint is an example of an abrasive suspended in a liquid, paste or wax, as are some polishing liquids for silverware and optical media. The liquid, paste or wax acts as a binding agent that keeps the abrasive attached to the cloth which is used as a backing to move the abrasive across the work piece. On cars in particular, wax may serve as both a protective agent by preventing exposure of the paint of metal to air and also act as an optical filler to make scratches less noticeable. Toothpaste contains calcium carbonate or silica as a “polishing agent” to remove plaque and other matter from teeth as the hardness of calcium carbonate is less than that of tooth enamel but more than that of the contaminating agent.

Very fine rouge powder was commonly used for grinding glass, being somewhat replaced by modern ceramics, and is still used in jewellery making for a highly reflective finish.

Cleaning products may also contain abrasives suspended in a paste or cream. They are chosen to be reasonably safe on some linoleum, tile, metal or stone surfaces. However, many laminate surfaces and ceramic topped stoves are easily damaged by these abrasive compounds. Even ceramic/pottery tableware or cookware can damage these surfaces, particularly the bottom of the tableware, which is often unglazed in part or in whole and acts as simply another bonded abrasive.[4]

Metal pots and stoves are often scoured with abrasive cleaners, typically in the form of the aforementioned cream or paste or of steel wool and non woven scouring pads which holds fine grits abrasives.

Human skin is also subjected to abrasion in the form of exfoliation. Abrasives for this can be much softer and more exotic than for other purposes and may include things like almond and oatmeal.[5] Dermabrasion and microdermabrasion are now rather commonplace cosmetic procedures which use mineral abrasives.

Scratched compact discs and DVDs may sometimes be repaired through buffing with a very fine compound, the principle being that a multitude of small scratches will be more optically transparent than a single large scratch. However, this does take some skill and will eventually cause the protective coating of the disc to be entirely eroded (especially if the original scratch is deep), at which time, the data surface will be destroyed if abrasion continues.

Choice of abrasive[edit]

The shape, size and nature of the workpiece and the desired finish will influence the choice of the abrasive used. A bonded abrasive grind wheel may be used to commercially sharpen a knife (producing a hollow grind), but an individual may then sharpen the same knife with a natural sharpening stone or an even flexible coated abrasive (like a sandpaper) stuck to a soft, non-slip surface to make achieving a convex grind easier. Similarly, a brass mirror may be cut with a bonded abrasive, have its surface flattened with a coated abrasive to achieve a basic shape, and then have finer grades of abrasive successively applied culminating in a wax paste impregnated with rouge to leave a sort of “grainless finish” called, in this case, a “mirror finish”.

Also, different shapes of adhesive may make it harder to abrade certain areas of the workpiece. Health hazards can arise from any dust produced (which may be ameliorated through the use of a lubricant) which could lead to silicosis (when the abrasive or workpiece is a silicate) and the choice of any lubricant. Besides water, oils are the most common lubricants. These may present inhalation hazards, contact hazards and, as friction necessarily produces heat, flammable material hazards.[6]

An abrasive which is too hard or too coarse can remove too much material or leave undesired scratch marks. Besides being unsightly, scratching can have other, more serious effects. Excessive abrasion or the presence of scratches may:

  • diminish or destroy usefulness (as in the case of scratching optical lenses and compact discs or dulling knives);
  • trap dirt, water, or other material;
  • increase surface area (permitting greater chemical reactivity such as increased rusting which is also affected by matter caught in scratches);
  • erode or penetrate a coating (such as a paint or a chemical or wear resistant coating);
  • overly quickly cause an object to wear away (such as a blade or a gemstone);
  • increase friction (as in jeweled bearings and pistons).

A finer or softer abrasive will tend to leave much finer scratch marks which may even be invisible to the naked eye (a “grainless finish”); a softer abrasive may not even significantly abrade a certain object. A softer or finer abrasive will take longer to cut, as it tends to cut less deeply than a coarser, harder material. Also, the softer abrasive may become less effective more quickly as the abrasive is itself abraded. This allows fine abrasives to be used in the polishing of metal and lenses where the series of increasingly fine scratches tends to take on a much more shiny or reflective appearance or greater transparency. Very fine abrasives may be used to coat the strop for a cut-throat razors, however, the purpose of stropping is not to abrade material but to straighten the burr on an edge. The final stage of sharpening Japanese swords is called polishing and may be a form of superfinishing.

Different chemical or structural modifications may be made to alter the cutting properties of the abrasive.[7]

Other very important considerations are price and availability. Diamond, for a long time considered the hardest substance in existence, is actually softer than fullerite and even harder aggregated diamond nanorods, both of which have been synthesised in laboratories, but no commercial process has yet been developed. Diamond itself is expensive due to scarcity in nature and the cost of synthesising it. Bauxite is a very common ore which, along with corundum’s reasonably high hardness, contributes to corundum’s status as a common, inexpensive abrasive.

Thought must be given to the desired task about using an appropriately hard abrasive. At one end, using an excessively hard abrasive wastes money by wearing it down when a cheaper, less hard abrasive would suffice. At the other end, if the abrasive substance is too soft, abrasion does not take place in a timely fashion, effectively wasting the abrasive as well as any accruing costs associated with loss of time.

Other instances of abrasion[edit]

Aside from the aforementioned uses of shaping and finishing, abrasives may also be used to prepare surfaces for application of some sort of paint of adhesive. An excessively smooth surface may prevent paint and adhesives from adhering as strongly as an irregular surface could allow. Inflatable tyre repair kits (which, on bicycles particularly, are actually patches for the inner tube rather than the tyre) require use of an abrasive so that the self-vulcanising cement will stick strongly.

Inadvertently, people who use knives on glass or metal cutting boards are abrading their knife blades. The pressure at the knife edge can easily create microscopic (or even macroscopic) cuts in the board. This cut is a ready source of abrasive material as well as a channel full of this abrasive through which the edge slides. For this reason, and without regard for the health benefits, wooden boards are much more desirable. A similar occurrence arises with glass-cutters. Glass-cutters have circular blades that are designed to roll not slide. They should never retrace an already effected cut.

Undesired abrasion may result from the presence of carbon in internal combustion engines. While smaller particles are readily transported by the lubrication system, larger carbon particles may abrade components with close tolerances. The carbon arises from the excessive heating of engine oil or from incomplete combustion. This soot may contain fullerenes which are noted for their extreme hardness—and small size and limited quantity which would tend to limit their effect.

Source: https://en.wikipedia.org/wiki/Abrasive

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