The earring coupling facilitates the transfer of material between two hoses or pipes. They are also called cam and groove couplings. Connecting and disconnecting them is simple and no tools are needed. They can eliminate the need for some traditional time-consuming connections, such as hose and pipe connections in other fittings. Their versatility, along with the fact that they are relatively inexpensive, make them the most popular connectors in the world. You can commonly find Camlocks used in industry, including manufacturing, agriculture, oil, gas, chemical, pharmaceutical, and military applications. This coupling is extremely versatile. Since it does not use threads, it is not a problem to get dirty or damaged. For this reason, earring couplings are very suitable for dirty environments. These couplings are ideal for situations where frequent hose changes are required, such as petrochemical and industrial trucks.
Figure 1: Earring coupling
How earring coupling works
The earring coupling assembly consists of two parts: a nargi branch and a pistil. Refer to Figure 2 for the diagram of components and the connection and disconnection process of Kamalak couplers.
Figure 2: Camlock coupler connection with plug: connection (1), assembly lock (2), disconnection (3).*
As indicated in the picture above (1), the coupling handle should be pulled out and the correct oleander should be inserted into the female connector. The two halves must be tightly locked together by closing both handles at the same time (2). Simultaneous closing of both handles ensures that the grooved plug is continuously pressed down on the seal, ensuring a leak-proof assembly for safe transfer of fluids. Make sure the hose assembly is pressurized before reversing the process to disconnect (3).
Selection criteria for earring coupling
To ensure a proper installation of your app, there are several factors to consider before making a purchase. Below is a list of the main selection criteria for earring couplings.
Size:
The sizes of earring couplings are determined by their nominal size, where female and male couplings have slightly different sizes for connection purposes. The male branch (B) is measured outside, while the pistil connection is measured inside (A), see Figure 3.
Figure 3: Camlock couplings and plugs have slightly different sizes, so female couplers are measured from the inside (A), while male plugs are measured from the outside (B).
B (mm/inch) | A (mm/inch) | Nominal size [inch] |
32.1/1.26 | 32.4/1.28 | 3/4 |
36.7/1.44 | 37.3/1.47 | 1 |
45.5/1.79 | 46.0/1.81 | 4/11 |
53.4/ 2.10 | 54.0/2.13 | 2/11 |
63.0/2.48 | 63.8/2.51 | 2 |
91.5/3.60 | 92.2/3.63 | 3 |
119.5/4.70 | 120.3/4.74 | 4 |
Temperature: The connection temperature specifications are determined by the selected material. For example, 70 °C or 158 °F is the maximum temperature that polypropylene can withstand, at which pressures must be reduced by 40 be. When stainless steel is used, the operating temperature is from -150°F to +500°F (-101°C to +260°C). Because of these differences, it pays to know the exact details and operating temperatures of your application. Keep in mind that the minimum and maximum operating temperature depends on various factors in addition to the material the camlock is made of. These include operating pressure, media used, external factors such as weather, etc. Materials: The table below shows the advantages and disadvantages of each material and how to use it for different applications.
Application | defect | Advantage – benefit – benefit – benefit | characteristic | item |
Acids, alkalis and highly corrosive areas | High cost | * Clean the inner wall * Thermodynamic resistance * High strength | * Corrosion resistant * Compatible with various media * Long lasting | stainless steel |
* Acidic and alkaline environments * Transfer of liquids in chemical industries * Agricultural irrigation programs | * Low resistance * Easy deformation | * Leak proof * Light weight * Low price * Easy operation | * Low density * Works for acid, alkaline and organic solutions * Chemically stable * Anti-aging | PP |
* Acidic and alkaline environments * Transfer of liquids in chemical industries * Agricultural irrigation programs | * Low resistance * Easy deformation | *Leak proof* Light weight* Cost effective* Easy to work with | * Good heat resistance * Higher density than PP * Resistant to moisture change | Nylon |
* Salt water and any environment except acid and alkali * Marine applications * Deep well operations | High cost | Easy to collect | *electrical conductivity* resistant to sea water | brass |
Fresh water mixture | *Compared to stainless steel, corrosion resistance is weak.* Susceptible to mold and oxidation | Affordable | * Low density, high intensity * Good flexibility * Electrical and thermal conductivity | aluminium alloy |
Coatings: There are complete couplers that are specially coated to protect them against very aggressive chemical agents. This is because some standard materials, such as stainless steel, cannot withstand those conditions. These are: ECTFE (ethylene chlorotrifluoroethylene): connectors coated in ECTFE excellent electrical insulation, fire resistance They are resistant to corrosion and can withstand temperatures up to 150 degrees Celsius. These fittings are designed to withstand highly concentrated and aggressive chemicals. PFA (PerfluoroAlkanes): PFAs are especially suitable for use in the food and pharmaceutical industries due to their high temperature resistance. PTFE (Polytetrafluoroethylene/Teflon): These coatings can withstand temperatures up to 260°C and are as effective as PFA coated couplings for food grade applications. PVDF (Polyvinylidene Difluoride): Coatings are wear resistant and also suitable for food industry applications. They are resistant to very concentrated and aggressive chemicals and have the advantage of high temperature resistance up to 260 degrees Celsius. Maximum Operating Pressure: Refer to the table below for the maximum operating pressure rating for the earring coupling. Pressure rating is the pressure at ambient temperature. Specifications of the pressure rating:
8″ | 5″ – 6″ | 4″ | 3″ | 2 1/2″ | 2″ | 1 1/2″ | 1 1/4″ | 1″ | 3/4″ | 1/2″ | Nominal coupling size/material |
150 | 75 | 100 | 125 | 150 | 250 | 250 | 250 | 250 | 250 | 150 | Aluminum PSI |
10.34 | 5.17 | 6.89 | 8.61 | 10.34 | 17.23 | 17.23 | 17.23 | 17.23 | 17.23 | 10.34 | Aluminum rod |
– | 75 | 100 | 200 | 225 | 250 | 250 | 250 | 250 | 250 | 150 | SS 316 PSI |
– | 5.17 | 6.89 | 13.78 | 15.51 | 17.23 | 17.23 | 17.23 | 17.23 | 17.23 | 10.34 | SS 316 Bar |
50 | 75 | 100 | 125 | 150 | 250 | 250 | 250 | 250 | 250 | 250 | Brass PSI |
3.44 | 5.17 | 6.89 | 8.61 | 10.34 | 17.23 | 17.23 | 17.23 | 17.23 | 17.23 | 17.23 | brass rod |
– | – | 50 | 50 | – | 100 | 100 | 100 | 100 | 100 | 75 | PP PSI |
– | – | 3.44 | 3.44 | – | 6.89 | 6.89 | 6.89 | 6.89 | 6.89 | 5.17 | PP Bar |
– | – | 50 | 50 | – | 100 | 100 | 100 | 100 | 100 | – | Nylon PSI |
– | – | 3.44 | 3.44 | – | 6.89 | 6.89 | 6.89 | 6.89 | 6.89 | Nylon tape |
Absolute standards for production
AA-59326D (previously Mil-C-27487
Mil-C-27487, now superseded by AA-59326D, was the U.S. Army specification for bolted joints. Although the original standard was superseded by a new standard, the US still guarantees the interchangeability of couplers of the same design. Mil-C-27487 specifies casting processes, materials, dimensions, tolerances, pressure ratings, and inspection methods.
EN 14420-7
The EN 14420-7 standard, a European standard that replaces the US military standard, was approved by the European Standards Committee, CEN, in September 2004. However, this American standard only fixes the connecting side, but not the connecting side. Other parts such as levers, screws, rings and seals are not standard. EN 14420-7 seeks to correct this issue.
Interchangeability
Other than 12″, 5″ and 8″, Camlock couplers are interchangeable between manufacturers. Since there are two types of camlock couplers on the market today, military specification AA-59326A does not apply to the 5″ and 8″ cam and groove couplers. There are differences between camlock couplers in terms of hose tail design, threads, and number of pieces. There are those manufactured to EN 14420-7 and those manufactured to MIL-C-27487. A smooth thread seal is added to the threaded parts of the material, and a smooth hose pipe according to EN 14420-7 / DIN 2828 is added for use with safety clamps according to EN 14420-3 / DIN 2817.
The quality of earring coupling
It is important to know the manufacturer of the earring coupling. Even if they are made to the same standard, slight differences in manufacturing methods may cause fittings from one manufacturer to not fit the other. This issue is not only a problem when dealing with cheap earring couplings. Make sure the couplers are of high quality and sourced from a reputable manufacturer. Ideally, the plug and connector are from the same manufacturer.
Types of earring couplings
Stud couplings are identified by their type designation, which is listed below while the image provides a visual reference for the various types of couplings.
Type A: plug with female thread
Type B: Connector with male thread
Type B-AS: connector with welded ends
Type C: Coupler with hose tail
Type D: connector with female thread
Type E: plug with hose tail
Type F: plug with male thread
Type F-AS: Plugs with welding connection
Type DC: Dust Cap for plug
Type DP: Dust Plug for Couplers
DA type: female and male with male adapter
Coupling accessories
All metal ring couplings and polypropylene fittings are supplied with NBR, EPDM or PTFE (Teflon) seals. Various sealing compounds are available depending on the media conveyed through the fittings. Replacement seals made of the following materials are available:
- FKM (FPM) (Hypalon)
- Teflon (PTFE) / NBR compound
- Teflon (PTFE) / FPM compound
For applications requiring more exotic sealing solutions, chemically encapsulated seals made of silicone or FEP are available.
Figure 6: Ring couplings with safety levers sometimes have an additional r-clip for safety. When the levers (B) are closed and the coupler is connected, the clamp (A) can be inserted into the connecting hole (C). R
Clips are designed to be used with earring couplings to prevent accidental disconnection of the coupling assembly. As seen in Figure 4, the clip R (A) can be pushed through a hole (C) behind the handle (B) to prevent the handle from loosening after the plug is attached to the coupling. R Clips are only used as an additional safety feature to prevent both camlock parts from getting caught or coming loose. Locking System: An alternating design of camlock couplers with automatic locking arms to prevent inadvertent disconnection, resulting in It is designed to fall. This is especially important if the environment contains highly flammable or toxic liquid chemicals. The Camlock fittings shown in Figure 5 are designed to have an internal automatic locking system.
Figure 7: Camlock locking system
Special hours
Special camlocks are available for non-standard applications. In this section, there is an overview of the connections of Kamklak-less and where they are used. * Undercut DIN 2828: Generally, Undercut DIN 2828 is used where there is a male thread on a parallel hose and provides an undercut at the base of the thread as well as a washer to seat the male thread.* Flanged: Flanged end An earring coupling is available so that the quick release system can be incorporated without the need for major plumbing changes.* Spiral Tail Camlocks: Spiral Tail Camlocks and Spiral Tail Camlocks can be used on composite hoses to match the internal helix of the hose. did A recessed ferrule secures the connection to the composite hose.* Camlock Plugs and Caps: Available from Dust Plugs (Type DP- Dust Plug for connectors) and Dust Caps (Type DC- Dust Cap for plugs) with a variety of B, C and D are used to seal the joint ends. * EN14420-7 (DIN2828) Smooth Tail Coupling: The smooth tail of Part C and Part E couplings has an annular collar, allowing the BS EN14420-3 lipped clamp to engage behind the collar. By doing this, there is less risk of damaging the hose.* Safety Bumps for Ring Coupling: Safety bumps are mechanisms used to extend the life of the hose assembly and keep it clean when not in use and prevent leaks.* Lock Safety locks for earring coupling: If safety locks are used, camlock arms will not open unintentionally. They are an alternative to more expensive locking knobs and are easy to install and remove.* Earring Coupling Chain: These chains can be used to connect a DP dust plug or DC round cap to a B type coupling or plug. C and D used. The flat tail of Part C and Part E couplings has an annular collar and allows the BS EN14420-3 lipped clamp to engage behind the collar. By doing this, there is less risk of damaging the hose.* Safety Bumps for Ring Coupling: Safety bumps are mechanisms used to extend the life of the hose assembly and keep it clean when not in use and prevent leaks.* Lock Safety locks for earring coupling: If safety locks are used, camlock arms will not open unintentionally. They are an alternative to more expensive locking knobs and are easy to install and remove.* Earring Coupling Chain: These chains can be used to connect a DP dust plug or DC round cap to a B type coupling or plug. C and D used. The flat tail of Part C and Part E couplings has an annular collar and allows the BS EN14420-3 lipped clamp to engage behind the collar. By doing this, there is less risk of damaging the hose.* Safety Bumps for Ring Coupling: Safety bumps are mechanisms used to extend the life of the hose assembly and keep it clean when not in use and prevent leaks.* Lock Safety locks for earring coupling: If safety locks are used, camlock arms will not open unintentionally. They are an alternative to more expensive locking knobs and are easy to install and remove.* Earring Coupling Chain: These chains can be used to connect a DP dust plug or DC round cap to a B type coupling or plug. C and D used. Safety bumps are mechanisms that are used to extend the life of the hose assembly and keep it clean when not in use and prevent leaks. become They are an alternative to more expensive locking knobs and are easy to install and remove.* Earring Coupling Chain: These chains can be used to connect a DP dust plug or DC round cap to a B type coupling or plug. C and D used. Safety bumps are mechanisms that are used to extend the life of the hose assembly and keep it clean when not in use and prevent leaks. become They are an alternative to more expensive locking knobs and are easy to install and remove.* Earring Coupling Chain: These chains can be used to connect a DP dust plug or DC round cap to a B type coupling or plug. C and D used.
Safety: Camlock and preventive maintenance:
You should have a routine maintenance schedule that allows you to inspect your earring couplings often. Regular inspection and replacement of worn parts in Kamlak couplings is very important because the moving parts are subject to wear and tear. By replacing worn parts, you increase the life of your products and ensure compliance with safety and health standards.