There is a proper way of installing or even repairing pipe fittings and other plumbing supplies. This is true even in various applications, whether residential, commercial, or industrial. Some installers even have special training. There are also special methods of handling, depending on the kind of setting. For example, the ways could be different if it is for hydraulics, heating ventilation, and air conditioning systems, as well as manufacturing and even refineries. If you are into this kind of business, there are a few things that you need to look into first. Three of these are the following aspects.

Different Kinds of Pipes

Firstly, there are various kinds of gas pipe fittings available in the market today. There are at least five general types, which are made from steel, copper, aluminum, as well as glass, and even plastic. The black iron pipe was once considered a popular option for water supply and even flammable gases. The copper pipes could either be soft or rigid type. The former type has flare connections while the latter has the soldered, compression, and crimped or pressed types of connections. The aluminum type is popular for being low-cost and resistant to solvents and corrosion.

What are the occupational hazards?

Secondly, since there are dangerous and hazardous materials involved in the process of installing or repairing pipe fittings, people who are doing the job are exposed to various occupational hazards. Some of these materials include asbestos, ammonia, lead, flammable gases, steam, as well as resins, and even solvents. However, there are already lots of significant efforts to reduce and eliminate exposure of workers to these hazardous materials nowadays. This is also true with liquefied petroleum gas or LPG gas fittings. Most countries also have regulations and laws pertaining to the use of those materials, specifically the usage of asbestos and even refrigerants.

What is their scope of work?

Thirdly and lastly, the scope of the work of fitters who will install or repair LPG fitting or other plumbing supplies varies as well. It depends on the coverage or design of the project that they are undertaking. There are some who are involved in blueprint reading too. As a matter of fact, this is very essential, most especially in big installation or repair projects. The other part of their job also includes detailing, computer-aided design (CAD) drawing coordinators, layout, pipe threading or grinding, as well as welding, and even plasma cutting.

I am Clair Woolner. I have a lot of experience in writing about gas equipment, cookers, hoses and gas pipe fittings and plumbing supplies, etc.

Hydraulic hoses are utilized in countless numbers of industries, but there’s one thing that unites all of them – immense pressure. Though hydraulic fittings are designed to tolerate this kind of heavy use and abuse, they have been known to break down with time or suffer severe damage in an accident.

In these situations, you’ll need to replace them immediately to prevent any further damage to your hose or, indeed. any equipment that’s relying on them. Replacing a hydraulic hose fitting is something you can do, regardless of whether you have any mechanical or plumbing experience, though if you’re unsure about the procedure, a qualified plumber or mechanic can do the job.

If you choose to go it alone though, you’ll need a few tools. They are; new hydraulic hose fittings; chains; clamps; a pipe wrench; a multi-purpose wrench; rags; buckets; suitable clothing; working gloves and protective eyewear.

Right, let’s get started:

Step One: Find the problem areas and relieve the pressure on the hydraulic cylinders

Perform a visual inspection of the hydraulic pump to figure out the extent of the damage suffered. To find the damaged fittings and leaking hoses, lay them on the ground in a well-lit area and check carefully. Anything that looks suspect should be marked.
Then you need to relieve the pressure on the hydraulic cylinders in order to prevent a blow-out or serious injury as you move on to step two.

Step Two: Remove the hose components

In order to remove the fittings, you’re going to have to remove some of the components in the hydraulic hose, including the guards, the clamps, and the housing. It’s always best to take pictures of each step of removal, so you can recall which part goes where when you reassemble later. With the photos taken, label each part and place them on one side.

Step Three: Remove the offending hose fittings

The majority of hose fittings swivel when the hydraulic pump is turned on, so you’ll need two wrenches in order to remove the swiveling parts – one to hold, and one to turn. Most fittings have two couplings, so that’s where you should place your wrenches.

If you find they’re stuck, try using some lubricant to loosen the couplings. If you’re removing the hose too, you’ll need to loosen the fittings attached to the hose and pull them out.

Step Four: Replace the fittings

Get your new fittings and clean them to ensure that no debris, dirt, or dust enters the system, as this can have a devastating effect on the safety and efficacy of your machine. With that done, take a look at the pictures you took of the disassembly procedure, repeating that in reverse, ensuring that everything is in the correct place and that your cylinder pins are in place before your snap rings are added.

Double ferrule tube fittings

There are 3 main mechanical methods for connecting two lengths of tubes together.

1. Flared fittings – where the end of the tube is flared with a tool and then contained within a nut, sleeve, and body.
2. Single ferrule fittings – where the ends of the tube are placed into a fitting with a single compression ring, a body, and a nut.
3. Double ferrule fittings – where the ends of the tube are placed into a fitting with two separate compression rings, body, and nut. (Also known as the twin ferrule fitting, this is not strictly correct as the two rings are of different shapes and lengths.)

For the purposes of this article, the focus will be on the double ferrule fitting.

This style of fitting, like all the others, has one basic function. To securely join tubes together in a safe, seal-tight assembly. Close tolerance machining on high-quality CNC machines allows for consistent production of all components.

The double ferrule fitting has the ability to lock onto the tube with a ‘double bite’ feature. Each ring bites into the tube giving two separate sealing areas. This style of fitting does so without transmitting torque or twisting the tube ensuring that the tube does not become ‘stressed’. Therefore, the mechanical properties of the tube are maintained. A further sealing point occurs at the bottom of the tube abutment. The abutment has an angle that the tube is forced into when the rings bite and drive the tube forward.

With stainless steel fittings, the problem of galling is resolved by the use of silver plating. The internal parts of the nut are the only areas that are plated.

Materials such as high Nickel alloys, high-temperature alloys, duplexes, and super duplexes are coated with an anti-gall agent in the same way. However, Molybdenum Disulphide can be used as an alternative. These materials are selected in order to be compatible with the fluid media contained within them. For chemical stability, the ideal situation is that both tubes and fittings are manufactured from the same material type.

There are strict assembly instructions to follow with this product type. The rule states that for the majority of sizes 1-1/4 rotations of the nut, from the finger-tight position, will give the correct seal-tight assembly. It is permissible to further ‘snug’ the fitting if a minor leak appears but this is normally unnecessary.

When access to any system is required these fittings provide an excellent ‘break-in’ point. The joint can be made and re-made many times over without loss of sealing integrity, providing the correct installation instructions are followed.

The strength of the fitting is such that the tube contained will burst before the fitting shows any sign of a leak or movement. This is subject to certain constraints on the wall thickness of the tube. If the wall is too heavy the rings will not bite as well, as when the tube wall is too thin, the tube will collapse rather than allow the rings to bite fully. Reference to the manufacturer’s product information should be made in all instances. The tube should generally have a hardness of no more than 80 on the Rockwell ‘B’ scale.

There are a number of manufacturers of this product type around the world and they generally contain the term ‘LOK’ in their product name. The major manufacturers encourage users of this product type not to inter-change different products. It is deemed as sacrilege to mix parts from different producers. It must be realized that, with the possible exception of two manufacturers, all bar none are based on the same original design. (The same inventor then went on to design a further two versions of the original design, the two exceptions mentioned previously.) Interchangeability in this product is actually advertised as a positive by some companies. Those same companies quite often offer part number cross-referencing in their product literature.

This product is used in many industries including the following:

1. Petrochemical
2. Oil & Gas
3. Water
4. Paper production
5. Hydraulic
6. High-pressure systems.
7. Nuclear
8. Offshore
9. Pharmaceuticals
10. Food & Beverage
11. Pneumatics
12. Cryogenics
13. Emission control

Fittings are produced in a vast range of styles with manufacturers offering tees, elbows, unions, male connectors, female connectors, and many others. Reducers allow the installers to change from one tube size to another, even from metric to imperial. Unlike the flared fitting, there is no set standard to manufacture double ferrule fittings. However, certain unwritten rules apply and all producers use the same method of distinguishing between metric and imperial fittings. A step, or shoulder, is machined onto the metric fitting body below the hexagon portion, and on the front end of the nut. This is also clearly seen in all the manufacturers’ literature.