Usage:
SEBF8176-01
September 2000
SMCS Code: 5057
GUIDELINE FOR
REUSABLE PARTS
AND SALVAGE OPERATIONS
Reusable Couplings For Caterpillar XT-3, XT-5, and XT-6 Hose
Summary of Revisions |
|
Page |
Description |
All |
Revised format. |
Contents
Introduction |
1 |
Summary |
2 |
Nomenclature for Hose Coupling |
2 |
Coupling Identification |
3 |
Reconditioning Procedures |
3 |
General Information |
3 |
Reconditioning the Flange Head |
4 |
Reconditioning Specifications |
4 |
Flange Head Couplings |
4 |
Face Seal Couplings |
5 |
Visual Inspection |
5 |
Head |
7 |
Outside Stem |
8 |
Inside Stem |
9 |
Collet |
10 |
Sleeve |
10 |
Introduction
This guideline enables dealers and their customers to benefit from cost reductions made possible through an established parts reusability and salvage program. Every effort has been made to provide the most current and relevant information known to Caterpillar Inc. Since the Company makes ongoing changes and improvements to its products, this guideline must be used with the latest technical information available from Caterpillar to ensure such changes and improvements are incorporated where applicable.
For questions or additional information concerning this guideline, contact Caterpillar Service Support Division, Dealer Support (309) 675-5156.
Summary
XT-3, XT-5, and XT-6 reusable hose couplings can be reused many times as long as they are not damaged in certain areas. The only repair method that applies to hose couplings are light deburring. This guideline presents reconditioning procedures, specifications, and visual examples of various "Use again" and "Do not use again" conditions.
For the proper assembly procedures for reusable hose couplings, refer to Special Instructions, SEHS7957, "Use of 6V-4900 Hydraulic Hose Service Press Arrangement".
Nomenclature for Hose Couplings
|
Illustration 1
Coupling Nomenclature. See Chart A.
Chart A |
|
Item |
Description |
1 |
Flange Head |
2 |
Ring Groove Land |
3 |
Outside Stem |
4 |
Collet |
5 |
Fingers |
6 |
Inside Stem ? |
7 |
Stem Taper |
8 |
Grip Grooves |
9 |
Swivel Nut |
10 |
Seal Face |
Coupling Identification
|
Illustration 2
Coupling identification.
(11) XT-3 (
∆) Coupling and Sleeve(12) XT-5 (+) Coupling and Sleeve
(13) XT-6 (UHP) Coupling and Sleeve
Identification Symbol |
Hose Type |
Hose ID |
Maximum Working Pressure |
Head Flange Thickness |
∆ |
XT-3 |
9.5 |
28,000 |
6.73 |
∆ |
XT-3 |
12.7 |
28,000 (4,000) |
6.73 |
∆ |
XT-3 |
19.1 |
28,000 (4,000) |
6.73-8.00 |
∆ |
XT-3 |
25.4 |
28,000 (4,000) |
8.00-9.50 (.315-.375) |
∆ |
XT-3 |
31.8 |
21,000 (3,000) |
8.00-9.50 (.315-.375) |
∆ |
XT-3 |
38.1 |
17,500 (2,500) |
8.00-9.50 (.315-.375) |
∆ |
XT-3 |
50.8 |
17,500 (2,500) |
9.50 |
+ |
XT-5 |
All |
35,000 (5,000) |
14.22 (.560) |
UHP |
XT-6 |
All |
42,000 (6,000) |
14.22 (.560) |
Note
: All dimensions are in mm (in) and all pressure is in kPa (psi).Reconditioning Procedures
General Information
The reconditioning procedure can be used on a coupling. After reconditioning, the coupling may meet "Use again" specifications and thus be re-used. Since a coupling is part of a pressure containment system, all that can be done to recondition the coupling is to remove burrs or raised metal. These flaws can prevent a seal connection from being leak-free or can cause damage to the hose-to-coupling joint.
Reconditioning the Flange Head
|
Illustration 3
Flange face has minor surface damage with "high" spots.
Use again---
after removing the high spots.
(7B-0337 Plate) or other flat surface.
Note:
Some sandpapers may also be suitable for this procedure. The emery cloth can also be "wet" with clean petroleum solvent in order to reduce friction.
|
Illustration 4
Removing burrs and raised metal from the flange face using medium grit emery paper.
Most burrs or high spots can be removed in two to six strokes. Once the surface has been sanded, look for areas that do not shine. These areas mean that the raised metal around a burr or dent has not been removed. If the face has not cleaned up, repeat the reconditioning procedure.
|
Illustration 5
Flange head minimum thickness.
Do not remove more than 0.08 mm (0.003 inch) from the face of the flange. It is not necessary to polish the face to a fine finish since an O-ring, rather than the face, makes the seal.
|
Illustration 6
Flange face after refinishing. Minor dents remain, but "high" spots have been removed.
Use again
Reconditioning Specifications
Flange Head Couplings
Do not remove too much metal from either the face or the back of the coupling flange. If the flange is too thin, the split clamps will contact the mating part without clamping the coupling head or compressing the O-ring. This can result in a leaking connection.
Chart D. |
|||
Hose |
Head |
Nominal |
"Do Not |
XT-3 |
30.2 (1.19) |
6.73 (0.265) |
6.65 (0.262) |
XT-3 |
38.1 (1.50) |
6.73 (0.265) |
6.65 (0.262) |
XT-3 |
44.5 (1.75) |
8.00 (0.315) |
7.92 (0.312) |
XT-3 |
50.8 (2.00) |
8.00 (0.315) |
7.92 (0.312) |
XT-3 |
60.3 (2.38) |
8.00 (0.315) |
7.92 (0.312) |
XT-3 |
71.4 (2.81) |
9.50 (0.374) |
9.42 (0.371) |
XT-3 |
84.1 (3.31) |
9.50 (0.374) |
9.42 (0.371) |
XT-5 |
All Sizes |
14.22 (0.560) |
14.15 (0.557) |
XT-6 |
All Sizes |
14.22 (0.560) |
14.15 (0.557) |
Note:
All dimensions are mm (in).Face Seal Couplings
Although not retained by clamps, O-ring face seal heads are similar to O-ring flange heads and the flange thickness should not be reduced beyond the dimensions shown in Chart D.
Chart D. |
|||
Hose |
Head |
Nominal |
"Do Not |
XT-3 |
9.5 (0.380) |
4.50 (0.177) |
4.42 (0.174) |
XT-3 |
12.70 (0.500) |
5.00 (0.197) |
4.93 (0.194) |
XT-3 |
19.10 (0.750) |
6.50 (0.256) |
6.43 (0.253) |
XT-3 |
25.40 (1.00) |
7.00 (0.276) |
6.93 (0.273) |
XT-5 |
19.10 (0.750) |
6.50 (0.256) |
6.43 (0.253) |
XT-5 |
25.40 (1.00) |
7.00 (0.276) |
6.93 (0.273) |
Note:
All dimensions are mm (in).Visual Inspection
Head
|
Illustration 7
O-ring flange head has minor surface damage on sealing lands.
Use again---
after ensuring no burrs protrude above flange face. See "Reconditioning Procedure".
|
Illustration 8
O-ring flange head has heavy damage across inner sealing land only.
Use again---
after ensuring no burrs protrude above flange face. See "Reconditioning Procedure".
|
Illustration 9
Back side of flange has raised burr.
Use again---
after deburring.
|
Illustration 10
O-ring flange head has heavy damage across the outer or both sealing lands.
Do not use again
|
Illustration 11
Flange face is distorted and not flat.
Do not use again
|
Illustration 12
Do not reuse or attempt to salvage any coupling that has a crack in the indicated area.
Do not use again
|
Illustration 13
JIC (Joint Industry Council) sealing seat with heavy damage.
Do not use again
|
Illustration 14
JIC swivel nut is cracked.
Do not use again
|
Illustration 15
ORFS sealing face has minor surface damage.
Use again---
after ensuring no burrs protrude above sealing face. See "Reconditioning Procedure".
|
Illustration 16
ORFS (O-ring face seal) sealing face has heavy damage.
Do not use again
|
Illustration 17
Male pipe threads have heavy damage.
Do not use again
Outside Stem
|
Illustration 18
Stem has been stretched, resulting in reduced stem OD.
Do not use again
|
Illustration 19
Stem has heavy exterior damage.
Do not use again
|
Illustration 20
Stem has failed due to excessive system pressure.
Do not use again
|
Illustration 21
Stem has been bent due to external forces.
Do not use again
Inside Stem
|
Illustration 22
Grip grooves have rubber fragments.
Use again---
after cleaning.
|
Illustration 23
Stem taper has a raised burr which will tear hose's inner liner.
Use again---
after deburring.
Do not reuse an XT coupling unless it is first resized. XT couplings that are not resized can separate (blow-off) from the hose assembly and possibly cause personal injury. |
|
Illustration 24
Resizing tool will not fit in end of coupling. Stem has not been resized.
Use again---
after resizing.
|
Illustration 25
Stem is not straight after resizing.
Do not use again
|
Illustration 26
The end of the stem has mushroomed.
Do not use again
Coupling
|
Illustration 27
Coupling has normal wear, minor dents, scratches, nicks, etc.
Use again
after reconditioning
by filing or sanding.It is permissible to use couplings that have had the zinc-chromate coating removed by bead blasting or exposure to non-caustic chemicals. Such couplings should be painted after they are assembled onto hoses to prevent corrosion damage.
|
Illustration 28
Coupling has been repaired by welding.
Do not use again
NOTE:
Caterpillar does not recommend welding on hose couplings. Welding could cause localized stresses which can lead to reduced fatigue strength and performance life.
|
Illustration 29
Coupling has been exposed to fire.
Do not use again
Collet
|
Illustration 30
Fingers have surface cracks in zinc-chromate coating.
Use again
|
Illustration 31
Finger has a raised burr(s).
Use again---
after deburring.
|
Illustration 32
Collet has a cracked or missing finger.
Do not use again
Sleeve
|
Illustration 33
Sleeve is cracked.
Do not use again
|
Illustration 34
Sleeve does not have a straight, cylindrical shape.
Do not use again
|
Illustration 35
Sleeve does not have a circular shape.
Do not use again