Page 1

1997 GUIDELINE for 45E E REFRIGERATION FLARE FITTINGS AND COPPER TUBING

Guideline M

4301 NORTH FAIRFAX DRIVE

!

ARLINGTON, VIRGINIA 22203


IMPORTANT

SAFETY RECOMMENDATIONS It is strongly recommended that the product be designed, constructed, assembled and installed in accordance with nationally recognized safety requirements appropriate for products covered by this guideline. ARI, as a manufacturer's trade association, uses its best efforts to develop guidelines, employing state-of-the-art and accepted industry practices. However, ARI does not certify or guarantee safety of any products, components or systems designed, tested, rated, installed or operated in accordance with these guidelines or that any tests conducted under its standards will be non-hazardous or free from risk.

Note: This is a new guideline.

Price $10.00 (M) $20.00 (NM) Printed in U.S.A.

ŠCopyright 1997, by Air-Conditioning and Refrigeration Institute Registered United States Patent and Trademark Office


TABLE OF CONTENTS SECTION

PAGE

Section 1.

Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Section 2.

Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Section 3.

Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Section 4.

Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Section 5.

Dimensions and Tolerances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Section 6.

Fitting Quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Section 7.

Forming Tube Flares . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Section 8.

Proper Handling and Storage of Flare Connectors . . . . . . . . . . . . . . . . . . . . 3

Section 9.

Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Section 10.

Remake and Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

TABLES Table 1.

ASTM Standard Dimensions for Coiled Copper Tubing . . . . . . . . . . . . . . . . 2

Table 2.

Dimensions of Single and Double 45-Deg. Flares for Tubing . . . . . . . . . . . . 4

Table 3.

Flare Nut Torque . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

FIGURES Figure 1.

Single and Double 45-Deg. Flares for Tubing . . . . . . . . . . . . . . . . . . . . . . . . 5

APPENDICES Appendix A.

References - Normative . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Appendix B.

References - Informative . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6


ARI GUIDELINE M-1997

45o REFRIGERATION FLARE FITTINGS & COPPER TUBING Section 1. Purpose

Section 4. Materials

1.1 Purpose. This guideline provides manufacturers, installers and servicing personnel with guidelines for acceptable practices for forming, installing, handling and servicing of fittings and copper tubing.

4.1 Fittings. Materials used in the manufacture of refrigeration flare fittings should conform to the latest edition of SAE J513, unless otherwise specified by the purchaser.

1.1.1 Intent. This guideline is intended for the guidance of the industry, including manufacturers, engineers, installers, contractors and users.

4.2 Tubing. The preferred copper tube for mating flares is Unified Numbering System (UNS) No. C12200 soft annealed temper (phosphorized, high residual phosphorous), any other tube should be soft annealed and conform to ASTM Standard B280. Only tubing designated as "Refrigeration Service" should be used.

1.1.2 Review and Amendment. This document is subject to review and amendment as technology advances.

Section 5. Dimensions and Tolerances Section 2. Scope 2.1 Scope. This guideline applies only to 45E flare fittings and copper refrigeration tubes; and only to refrigeration and air conditioning systems using halogenated hydrocarbon refrigerants. Topics addressed are: Factory workmanship, handling and storage, forming tube flares, joint assembly, remake, repair, and leak testing of assemblies. Double and single flared tubes and metal seal caps with copper gaskets are included within the scope of this guideline.

Section 3. Definitions 3.1 Definitions. All terms in this document will follow the industry definitions in the current edition of ASHRAE Terminology of Heating, Ventilation, Air-Conditioning and Refrigeration unless otherwise defined in this section.

5.1 Dimensions. Refrigeration fittings should dimensionally conform to SAE Standard J513, unless otherwise specified. 5.2 Conformance. The mating tubing flares should dimensionally conform to SAE Standard J533, unless otherwise specified. The wall thickness of the tubing should conform to ASTM Standard B280 as shown in Table 1.

Section 6. Fitting Quality 6.1 Quality. In addition to the materials dimensions tolerances and general specification of SAE Standard J513, tightened controls on concentricity and surface finish are recommended for refrigeration use. 6.1.1 Tool Marks. Only annular tool marks concentric with the center line of the sealing face should be permitted.

3.2 "Shall," "Should," "Recommended" or "It Is Recommended." "Shall," "should," "recommended" or "it is recommended" shall be interpreted as follows:

6.1.2 Finish. Surface of the flare face should not exceed a 63 microinch [1.6 Âľm] finish.

3.2.1 Shall. Where "shall" or "shall not" is used for a provision specified, that provision is mandatory if compliance with the standard is claimed.

6.1.3 Seating Surfaces. Seating surfaces should be smooth and free from nicks, pit marks, and any other defects that prevent sealing.

3.2.2 Should, Recommended, or It is Recommended. "Should," "recommended," or "it is recommended" is used to indicate provisions which are not mandatory but which are desirable as good practice.

6.1.4 Sealing Face. The sealing face of both male and female fittings should be concentric with the pitch diameter of the thread within 0.005 in. [0.127 mm] total indicator reading.

1


ARI GUIDELINE M-1997 Table 1. ASTM Standard Dimensions for Coiled Copper Tubing TolerancesB Standard Size, in.

Outside Diameter, in. [mm]

1/4 5/16 3/8 1/2 5/8 3/4

0.250 [6.35] 0.312 [7.92] 0.375 [9.52] 0.500 [12.7] 0.625 [15.9] 0.750 [19.1]

A

B

Wall Thickness, in. [mm]

0.030 [0.762] 0.032 [0.813] 0.032 [0.813] 0.032 [0.813] 0.035 [0.889] 0.035 [0.889]

0.002 [0.051] 0.002 [0.051] 0.002 [0.051] 0.002 [0.051] 0.002 [0.051] 0.0025 [0.064]

Wall Thickness, Plus and Minus, in. [mm] 0.0025 [0.064] 0.0025 [0.064] 0.0025 [0.064] 0.0025 [0.064] 0.0030 [0.076] 0.0035 [0.089]

The average outside diameter of a tube is the average of the maximum and minimum outside diameters as determined at any one cross section of the tube. The tolerances listed represent the maximum deviation at any point.

in a flaring bar. The flare cone spreads and pushes out the copper tube into the chamber area of the flaring bar.

6.2 Testing. Brass components of an assembled flare connection should pass the mercurous-nitrate test of Underwriters Laboratories Standard UL 207, with flare nuts tightened to recommended torque values. 7.3 Section 7. Forming Tube Flares 7.1 Types of Flares. There are two basic types of flares made by the air conditioning/refrigeration industry. 7.1.1 Single lap flare. Most commonly used by field servicemen because it is quick to make. It is made by flaring out the end of a piece of copper tubing to a 45E angle 7.1.2 Double lap flare. Made by belling the end of the piece of copper tubing, and then folding it together so that the flare has two thicknesses. The double flare is not commonly used. 7.2 Types of Tools. There are two basic types of flare tools. 7.2.1 Roll Type. The second and newer type of flaring tool is the preferred tool which flares the copper tube above the flaring bar. A big advantage is that there is no weakening at contact with the flaring bar. In effect, the flare is "rolled out" by the facets on the cone. 7.2.2 Compression Type. A compression type flare tool produces a flare by driving a non-rotating flaring cone into the end of the piece of copper tube, secured

2

AverageA Outside Diameter, Plus and Minus, in. [mm]

Steps in Flaring. 7.3.1 Tube Cutting. For an even flare it is recommended that a tube cutter be used in lieu of a hacksaw. The copper tubing should be cut off squarely. When the tube cutter tool is used correctly, there will be very little burr left on the inside of the tube. Cutting the tube too fast produces a larger burr on the inside of the tubing. Cutting the refrigerant tubing with a hacksaw is not recommended. Making a square cut with a hacksaw is difficult and metal particles may enter the tube. 7.3.2 Deburring the Tube. The purpose for deburring is to eliminate the burr which could break off and score or lodge in the flare seat and produce a defective flare. There are two common ways of deburring copper tubing in the field. The first is using a regular threebladed, barrel-type deburring tool. This tool will very effectively and efficiently remove burrs from the end of copper tubes. The second and more common way is using a knife. 7.3.3 Flaring the Tube. When using the rotating flaring tool, insert the soft copper tube through the flare bar far enough to allow a complete flare to be made above the flaring bar. If the flare tool is the compression type, the copper will be put in so that the


ARI GUIDELINE M-1997 end is slightly above the flare bar. Some tools in this category have automatic stops built into them so that the tubing cannot be put in too far.

9.2 Use of Gaskets. When brass-on-brass connections are made, a soft copper gasket should be used between mating surfaces.

7.3.3.1 Lubricating the Flare. It is a recommended practice to put a drop of refrigeration oil on the flare cone to insure that the cone will not stick or tear the copper flare while it is being made.

9.3 Joining. The mating faces of the fitting should be joined squarely, with no lateral or longitudinal strain on the fitting.

7.3.3.2 Flare Diameter. In the flaring process itself, the most important consideration is to not over flare. In the compression type of flare tool, there is a tendency to drive the flaring cone down too far, thereby thinning and weakening the flare. Over flaring can work-harden and thin out the copper tubing flare so it will become weaker and subject to failure. However, if the tube is under flared there will be insufficient engagement to the flare nut. The diameter of the finished flare should conform to Table 2. Inspect the flare for imperfections, contamination or for a split tube.

9.4 Tightening of Nuts. When tightening, two wrenches should be used. The fitting should be well supported by the stationary wrench. 9.5 Torque of Nuts. The nut should be torqued per the values shown in Table 3. The values shown are for singleflared copper tube with brass nut and fitting. Use of lubricants is not recommended. 9.5.1 Note that the torque above the maximum limit may distort the sealing surface of the fitting or tube, which in turn will reduce reliability of the flare seal.

Section 10. Remake and Repair Section 8. Proper Handling and Storage of Flare Connectors 8.1 Handling of Flares. Keep products having flare connections/individual connectors in original package until used. 8.2 Protection. Remove protection caps during installation only. Only use flare connectors that are properly factory protected. 8.3 Store flare fitting types together and in appropriately sized boxes. 8.4 Do not drop or scratch during storage and installation.

Section 9. Assembly

10.1 Remake. When separating a flared joint, two wrenches should be used. The fitting should be well supported by the stationary wrench. 10.2 Visual Inspection. Prior to reassembling a flared fitting, check the mating surfaces for the following: a. b. c. d. e.

Thinning of the flared tubing material. Cracked or split. Scoring or longitudinal tool marks. Cleanliness. If either of the sealing surfaces are deformed, they should be replaced.

10.3 Limitations. Flared joints are not field repairable. If any damage is found, the damaged portion should be cut from the tubing and the flare remade or a new fitting brazed on. Leaking fittings cannot be permanently repaired by using a sealant material or gasket cement on threads or cone face.

9.1 Assembly. Prior to assembling a flared fitting, check the mating surfaces for the following: a. b. c. d. e.

Thinning of the flared tube material. Cracked or split tube. Scoring or longitudinal tool marks. Cleanliness. Check threads and flare surfaces for any discontinuities.

3


4

6.35 7.94 9.52 12.70 15.88 19.05

1/4 5/16 3/8 1/2 5/8 3/4

0.325 0.404 0.487 0.623 0.748 0.916

Max

in.

0.315 0.388 0.471 0.607 0.732 0.900

Min

mm

8.25 10.26 12.36 15.82 18.99 23.26

Max

A Single Flare Diameter

8.01 9.86 11.97 15.42 18.60 22.86

Min 0.360 0.425 0.500 0.640 0.772 0.912

Max

in.

0.345 0.410 0.485 0.625 0.757 0.897

Min 9.14 10.79 12.70 16.25 19.60 23.16

Max

A1 Double Flare Diameter mm

8.77 10.42 12.32 15.88 19.23 22.79

Min 0.02 0.02 0.02 0.02 0.02 0.02

±0.01

in.

0.51 0.51 0.51 0.51 0.51 0.51

±0.25

mm

B Single Flare Radius

0.04 0.04 0.04 0.04 0.04 0.04

±0.01

in.

1.02 1.02 1.02 1.02 1.02 1.02

±0.25

mm

B1 Double Flare Radius

* Recommended maximum nominal wall thickness of tubing normally considered suitable for flaring to the above specifications.

Notes: A - See Figure 1 for Single Flare Diameter. A1 - See Figure 1 for Double Flare Diameter. B - See Figure 1 for Single Flare Radius. B1 - See Figure 1 for Double Flare Radius. C - See Figure 1 for Double Flare Coined Seat Length. D - See Figure 1 for Single Flare Wall Thickness. D1 - See Figure 1 for Double Flare Wall Thickness.

mm

in.

Nominal Tube OD

0.040 0.062 0.062 0.062 0.062 0.062

Min

in.

1.02 1.57 1.57 1.57 1.57 1.57

Max

mm

C Double Flare Coined Seat Length

Table 2. Dimensions of Single and Double 45-Deg Flares for Tubing

0.049 0.049 0.065 0.083 0.095 0.109

Min

in.

1.24 1.24 1.65 2.10 2.41 2.76

Max

mm

D* Single Flare Wall Thickness

0.035 0.035 0.049 0.049 0.049 0.049

Min

in.

0.83 0.88 1.24 1.24 1.24 1.24

Max

mm

D 1* Double Flare Wall Thickness

ARI GUIDELINE M-1997


ARI GUIDELINE M-1997

Figure 1. Single and Double 45-Deg. Flares for Tubing

Table 3 - Flare Nut Torque Torque, ft-lbs [N x m] Standard Size, in. 1/4

Minimum 8 [11]

Maximum 10 [14]

5/16

10 [14]

15 [20]

3/8

15 [20]

25 [34]

1/2

25 [34]

35 [47]

5/8

40 [54]

55 [75]

3/4

50 [68]

60 [81]

5


ARI GUIDELINE M-1997

APPENDIX A. REFERENCES - NORMATIVE None.

APPENDIX B. REFERENCES - INFORMATIVE B1 Listed here are standards, handbooks, and other publications which may provide useful information and background but are not considered essential. References in this appendix are not considered as part of this guideline. B1.1 ASTM Standard B280-93, Standard Specifications for Seamless Copper Tube for Air Conditioning and Refrigeration Field Service, 1992, American Society of Testing Materials, 100 Barr Harbor Drive, West Conshohocken, PA 19428, U.S.A. B1.2 SAE Standard J513-JUN90, Refrigeration Tube Fittings, 1990, Society of Automotive Engineers, Inc., 400 Commonwealth Drive, Warrendale, PA 15096, U.S.A.

6

B1.3 SAE Standard J533-JUN92, Flares for Tubing, 1992, Society of Automotive Engineers, Inc., 400 Commonwealth Drive, Warrendale, PA 15096, U.S.A. B1.4 UL Standard 207, Sixth Edition, 1993, Refrigerant Containing Components and Accessories, Non-Electrical, Underwriters Laboratories, Inc., 333 Pfingsten Road, Northbrook, IL 60062, U.S.A. B1.5 UNS, Unified Numbering System for Metals and Alloys, 1996, Copper Development Association Inc., 260 Madison Avenue, New York, NY 10016, U.S.A.

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REFRIGERATION FLARE FITTINGS AND COPPER TUBING  

45E E REFRIGERATION FLARE FITTINGS AND COPPER TUBING Guideline M 4301 NORTH FAIRFAX DRIVE ! ARLINGTON, VIRGINIA 22203

REFRIGERATION FLARE FITTINGS AND COPPER TUBING  

45E E REFRIGERATION FLARE FITTINGS AND COPPER TUBING Guideline M 4301 NORTH FAIRFAX DRIVE ! ARLINGTON, VIRGINIA 22203

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