GB2526524A

GB2526524A - Improvements to refrigeration purging adaptors

Info

Publication number: GB2526524A
Application number: GB1406800.1A
Authority: GB
Inventors: Ravinder Dhariwal
Original assignee: Individual
Current assignee: Individual
Priority date: 2014-04-15
Filing date: 2014-04-15
Publication date: 2015-12-02
Also published as: GB201406800D0

Abstract

An adapter 1B configured to enable a user to quickly and easily couple a fluid supply source 10 to a pipe 9 extending from a system to be brazed forming a substantially air-tight seal without requiring any bonding or adhesives. The adapter is preferably made of rubber and connects to the fluid supply source (10C, figure 4) by way of a screw thread (2, fig. 1). Each adapter will fit a single diameter of system pipe, and a set of colour coded adapters may be provided each of which fits a differently sized pipe.

Description

IMPROVEMENTS TO REFRIGERATION PURGING ADAPTORS

Field of the Invention

The embodiment of this disclosure relates to the field of providing a more suitable working method and preparation in relation to the maintenance of air conditioning and refrigeration systems. To include soldering, welding and brazing, tubing, especially copper pipe, in said refrigeration systems to reduce the formation of "black scale" or similar.

Background

The method of purging refrigeration pipework has been used for many years and more recent laws require the worker to possess a refrigeration certificate, such as F.Gas, to show they have been taught the correct procedure. If the worker is now found brazing without purging prior to this, they will invalidate the warranty which can affect business recall and safety or lifetime of the equipment involved. The adding of a steady flow of low pressure OFN (Oxygen Free Nitrogen) is common practice within this industry. This is administered to the pipe which is to be brazed, due to oxidization occurring during this process. This produces a type of ash substance which can damage the compressor of the air conditioning equipment once the system is engaged-The benefits of using dehydrated nitrogen while making brazed joints in a refrigeration system are well known in the art Many practitioners in this art have advocated the use of nitrogen during refrigerant line brazing for more than 20 years.

This is a natural chemical reaction and when brazing is conducted on copper tubing or any other copper surface, a quite significant portion of the copper will oxidize in the presence of oxygen resulting in a quantity of black scale. One standard procedure for eliminating this black scale (which is very detrimental to the normal operation of refrigerant line operation) is to subject the interior portion of copper tubing which is to be brazed with a low-pressure, low-volume supply of nitrogen. For example, a steady flow of nitrogen, at about five PSIG will result in a significant, if not total, reduction in the amount of black scale produced during brazing. This procedure is often utilized where copper is joined to copper or sometimes when copper is joined to other materials such as brass.

A heat source, normally over 20000 F. often through the use of a torch kit, is provided which is applied to the copper tubing and to a brazing alloy.

The brazing alloy then melts, and upon cooling effectively becomes a part of the piping material. Silver alloy brazing rod with a 15% silver content melts and flows at roughly 1500° F. The temperature between 1500° F. and 20,000° F. is high enough to cause a chemical reaction between the atmospheric oxygen inside the pipe and the interior surface of the pipe itself. The resulting black scale is cupric oxide (CuO). Cupric oxide is formed on a very unstable layer, approximately 0.002 inches thick, slightly less than the thickness of common newspaper. This layer of oxidized copper quickly separates and may circulate through the refrigeration system as a contaminant. Physical damage can occur at check valves, and solenoid, or switchover valves.

The components of a compressor are machined to extremely close tolerances; this paper-thin scale can damage these parts and others. Prior art attempts to pump out the system are not effective as this system does not remove solids from the piping system.

Other prior art attempts include blowing out" a system which also is ineffective in removing this black scale.

Attempts to improve the attachment of the piping have been cited and patent ref: US200912732 shows a method and approach to this. However, this design would not normally be able to be used in an upside down position to the pipe as it would detach itself or fall out and it would not be able to fit differing pipe diameters or sizes to support the various wall thicknesses of refrigeration pipe.

As pipework runs through a floor area, for example, in an office location, it is angled and levelled at differing measures and heights, as well as restricted space around the piping, therefore it is sometimes not possible or practical to have a position to apply this existing design.

A few refrigeration systems have been provided with an access stem fitting which allows for direct attachment of a fluid source. However, many of the refrigeration systems do not provide such an access stem fitting for ease of providing a dehydrated nitrogen while brazing and a worker would prefer a solution that is always available.

Prior art solutions to attaching the nitrogen source to the tubing of an air condition or refrigeration system involve normally positioning the end of the nitrogen source tubing to the end of an access tubing of the air condition or refrigeration system. At this point, a length of duct tape would be wrapped around the tubing and assembly, essentially closing off the system, such that the nitrogen would be injected into the refrigeration system, and upon which time brazing could be accomplished without producing black scale. This process has negative side effects, including the residue of the duct tape, and the time involved in attaching the apparatus, and detaching the duct tape when brazing was accomplished. Furthermore, the adhesive residue left over from duct tape negatively interferes with the refrigerant utilized, as well as in a brazing compound that should be desired on that surface. As with many working practices in many industries workers will attempt to proceed with none-practical solutions such as these and make do' with tape methods. This is an overlooked area that requires a practical and lower cost approach to provide a consistent long term and easily administered solution, to enable a more satisfactory and safe methodology that is in line with current rules and practice law. a

Summary of the invention

According to the present invention there is provided a hollow rubber or similar embodiment, having a form similar to that of a rounded vessel or bottle' shape. To the larger end of this infundibula form is a circular opening that is pliable and has a correctly faced edge to allow it to seal once in contact with a tubed surface.

To the more narrowed opposing end of the whole form is a much smaller opening having a suitably threaded plastic or similar fitting, which engages directly with the provider tubing from the source, which has the corresponding thread.

As the smaller threaded opening allows for a larger one opposite, the body and shape from the narrow hole to the larger is notably incurvate. This provides an improved shape for installation in confined locations allowing more space near to the threaded receiving hole and an overall more applicable form.

This adapter is then pressed onto the pipe extending from the refrigeration or conditioning system via use of the wider rubber opening within its body. These pipes vary in diameter and a selection of rubber openings would be required, thus a selection is advised of at least seven ascending adapters, each having a differing opening diameter to allow them each to suit differing pipe extension sizes. We suggest sizes of 1/4, 3/8, 1/2, 5/8, 3/4, 7/8, 1-1/8.

These would be colour coded, each size having a different colour to enable the worker or user to identify which size he is selecting from a distance or from inside a case or holder, within a tool bag or box. Examples would be, in order of the above sizes, Green, Orange, Black, Dark Red, Yellow, Grey and Purple being the larger of the range. These colours and even sizes are variable from this description and only represent known sizes and guides for current application and may adapt within the concept on emerging changes therein. The strong durable rubber of which these openings are made would also allow a tolerance of mm to enable the larger hole that fits over the pipe opening to alter slightly when pressed into place.

This flexible nature of the wider pipe connection hole provides a completely airtight filling once in place. In practice there is normally a coupling mechanism operatively configured to attach a fluid supply line to a system to be brazed. This is desired, for example, when a fitting or pipe is to be brazed to another filling or section of pipe. In one form the adapter comprises an access stem fitting which is configured to fixedly and removably couple to a fluid supply system. The coupling mechanism in this form includes an adapter portion, which is coupled to the access stem fitting. An adapter portion is also provided and is operatively configured to frictionally and removably couple to a pipe or filling extending from the system to be brazed. Thus, the adapter portion can be quickly and easily be attached to and removed from the fitting or pipe without deforming, or marking the filling or pipe, and without the use of any adhesives.

The adapter portion is thus operatively configured to leave no substantial mark or residue upon the filling or pipe which extends from the system to be brazed, The coupling mechanism further comprises a piping portion which extends from the first engagement surface of the access stem fitting. This piping portion connects the access stem portion, to the adapter portion.

In general usage the adapter portion comprises a selection of differing sized options in the aforementioned size ranges and any chosen colour or livery options, operatively configured to correlate to the diameter of the pipe extending from the system to be brazed. Thus, the adapter portion can be filled to pipes having a wide range of interior and/or exterior diameters.

Once connected to the pipe from the refrigeration unit the more narrowed and threaded end is attached to the OFN supply pipe from the bottle, as the threads of the adapter and the pipe filling correspond.

This threaded end may be comprised of a less expensive but comparably long lasting and wearing plastic or similar composite.

The passage of the OFN is then possible between the supply bottle and meter to the subject refrigeration or conditioning unit therein.

The coupling mechanism and adaptor is operatively configured to provide a substantially airtight seal between the adapter portion, and the pipe extending from the system to be brazed. This hinders the gas from venting prematurely to the outside air.

The adapter portion in each form may provide a seal sufficient to allow positive pressure within the system to overcome the frictional force of the adapter upon the pipe or fitting and "push" the adapter off the fitting when the brazing operation is complete.

In line with regulation, if there are more than two ends of the pipework configuration then other ends need to be sealed in similar manner, leaving just one open' end for the introduction of the OFN. The entry point of the OFN must be sealed around the entry pipe to prevent the induction of air.

A substantially airtight seal is provided by the rubbers frictional contact between a surface of the adapter portion, and a surface of the pipe extending from the system to be brazed, without marring the surface of the pipe or leaving any residue upon the surface of the pipe. The coupling mechanism in this rubber method provides a substantially airtight seal capable of holding positive interior pressure to that required to carry out the operation and to its higher levels and extents. This is ensured by the expansive nature of the rubber composite as it contacts with a surface. Certain rubbers have sealant properties and provide durable advantages, including vulcanized commercial types. The depth of which the pipe is inserted into the hollow interior of the adaptor body is also important and it must clear the opening lip into where it has been inserted by a sufficient degree.

As the body is a rubber composition, it is more adaptable in use due to its flexibility and shape/size. This enables the user to impart its use in more confined spaces under flooring or in areas where the adapter is in an upside down or at an undesired location such as a flection of pipe in a restricted access point.

The hollow interior itself has important responsibility to provide an even and exacting flow of the moving liquid or gas therein, this being aided by the interior having a void that is of a certain voluminosity to maintain flow pressure as delivered.

To provide these qualities the hollow rubber body is provided thus and this is reflected throughout the varying sizes and the associated shaping that may extend from those shown in the accompanying figures.

Brief description of figures

Figures 1 show an example of the adaptor.

Figures 2 show an example of the adaptor with a larger opening for a pipe.

Figures 3 show a working example of the adaptor being applied to both pipes.

Figures 4 show a typical purging system solution configuration with the adaptor in play.

Detailed description of figures

A typical embodiment of the invention is illustrated in Figure 1. The adaptor has a main body I which is of cylindrical nature and is hollow. To one end is a receiving collar which is threaded 2 which surround a supply hole 3 which leads into the hollow interior of the main body 1.

Opposite to the supply hole 3 is a large opening which is the opening to receive the refrigeration pipe 7. As a result of these opposing small and large holes the outer surface 5 is shaped accordingly as is the underside surface 6 adjoining and the form is maintained by a curved profile 4.

The main body I therefore forms a hollow chamber with an interior wall that has a ewer or bottle type appearance with a small opening 3 and large opening 7 to each concluding end therein, as shown in Figure 1, as a single example of at least seven different sizes.

An alternate size is shown in Figure 2, IA, wherein due to the larger opening to receive the refrigeration pipe 7A, the curved profile is thus larger and to accommodate the aggrandized shape an extended nose' 8 is apparent.

The main body lB is screwed onto the supply tube of the OFN 10 (Oxygen Free Nitrogen), which has a corresponding male and female thread, as shown and the whole hollow body is then inserted onto the pipe to the refrigeration unit 9, made possible by the accommodation of the hollow opening and interior II therein. The size of the opening 11 being chosen to suit the diameter of the pipe 9 from a selection of sizes.

The follow flow of OFN is then possible between all connected points, as shown in figure 4. The OFN bottle sends its contents through a flow meter 13 along the supply tube IOC, as shown.

The adaptor main body IC receives the OFN flow and thus is able to pass it in a fully sealed manner to the pipe to the refrigeration unit 9C.

As the thickness or diameter of pipes from many different refrigeration or conditioning units vary, the user will select which size of adaptor they require to suit each pipe as they work, from a selection housed in a kit. &

Claims

Claims 1. A refngeration purging adaptor wherein the nature of its configuration enables usage in adverse positions when connection to refrigeration piping is required.
2. A refrigeration purging adaptor as claimed in claim 1 wherein the configuration of the rubber press filling enables usage of the adaptor in upside down positions.
3. A refrigeration purging adaptor has a rubber hollow body that is pliable.
4. A refrigeration purging adaptor as claimed in claim 3 wherein the hollow rubber body is provided in a selection of colour coded size variants to enable selection and filling to differing sizes of refrigeration pipes.
5. A refrigeration purging adaptor is pushed into position and pulled to remove.
6. A refrigeration purging adaptor wherein once the adaptor is applied there would be no loss of OFN.
7. A refrigeration purging adaptor has a plastic variant threaded supply hole for reduced cost in manufacture.
8. A refrigeration purging adaptor wherein at least 7, seven, sizes of adaptor are housed and presented in a kit for selection.
9. A refrigeration purging adaptor wherein a refrigeration purging adapter may be installed in various angles and limited locations including upside down onto refrigeration piping, has a plastic composite threaded supply hole and provides filling for all sizes of piping by way of a selection of sizes in kit form for selection which are colour coded for identification, providing no loss of OFN therein.Amendments to the claims have been made as follows Claims 1. A refrigeration purging adaptor wherein the nature of its configuration enables usage in adverse positions, including upside down positions due to its design providing an attachment method that will not fall when in place, when connection to refrigeration piping is required.2. A refrigeration purging adaptor as claimed in claim 1 wherein the configuration of the rubber press fitting enables usage of the adaptor in upside down positions, as it will not fall or disconnect due to additional purchase provided by the nature of its rubber fitting.3. A refrigeration purging adaptor has a rubber hollow body that is pliable.4. A refrigeration purging adaptor as claimed in claim 3 wherein the hollow rubber body is provided in a selection of colour coded size variants to enable selection and fitting to differing sizes of refrigeration pipes.5. A refrigeration purging adaptor is pushed into position and pulled to remove.0 6. A refrigeration purging adaptor wherein once the adaptor is applied there would be no loss of OFN.C\J 7. A refrigeration purging adaptor has a plastic variant threaded supply hole for 0 reduced cost in manufacture.8. A refrigeration purging adaptor wherein at least 7, seven, sizes of adaptor are housed and presented in a kit for selection.9. A refrigeration purging adaptor wherein a refrigeration purging adapter may be installed in various angles and limited locations including upside down onto refrigeration piping, has a plastic composite threaded supply hole and provides fitting for all sizes of piping by way of a selection of sizes in kit form for selection which are colour coded for identification, providing no loss of OFN therein.