LUCKNOW - 226 011



(Revised 1998)


0.1 The Manual of instructions for fabrication, installation and maintenance of Glued Insulated Rail Joints was first issued in 1982. The manual was revised in 1989. This manual is issued under the title "MANUAL FOR GLUED INSULATED RAIL JOINTS" in consultation with Signal Directorate of RDSO (reference Signal Engg. Dte. letter No. STS/E/IRJ/PIJ dated: 20.6.97).

0.2 The Manual has been further revised in its present form in view of use of rails of different grades of steel such as GR 880, GR 1000 and GR 1080 and experience gained in the intervening period. The procedure for approval of new units for Glued insulated rail joints has also been included as annexure A.

0.3. For convenience GLUED INSULATED RAIL JOINTS" have been referred to ns "Glued Joints".

0.4 There are two types of glued joints namely G3(L) type having six bolts and G3(S)  type having four bolls. G3 (L) type and G3(S) type of glued joints can be manufactured from different rail sections as per drawing numbers given below:-

End post Thickness Rail Section

Drawing No.

G3 (L) Type G3 (S) Type
6mm .1  75 R RDSO/T - 1283 RDSO/T - 3008
. .2  90R RDSO/T - 1276 RDSO/T - 1278
. .3  52 kg RDSO/T - 671 RDSO/T - 1259
. .4  60 kg (UIC) RDSO/T - 2572 RDSO/T -2576
10mm .1 52 kg RDSO/T - 5361 .
. 2 60 kg (UIC) RDSO/T- 5843 .

Typical features of G3 Type Glued joints using 6 mm thick end post are as shown in Annexure 'H'.

G3(L) type glued joints are for use in LWR/CWR track in all the temperature zones and G3(S) type joints are for use in Fishplate track as well as in SWR track.




The requirement of material for fabrication of one glued joint is given in Annexure B. The input materials shall be procured from RDSO approved suppliers only.


The material shall be as per specifications given in Annexure C. The latest list of approved suppliers is at Annexure D which should be referred to. Updated/revised list will be circulated by RDSO once every year.


1.3.1 List of equipment required for fabrication of glued joints is given in Annexure E,

1.3.2  A special jig for assembly (item f of Annexure E ) and a testing frame (item g of Annexure E ) for conducting pull- out test on glued joints shall be manufactured as per guide lines shown in fig. 2 & 3 respectively:




2.1.1 The glued joints shall be fabricated/assembled in a covered shed having clean dust free and well lit area, so that there is no possibility of extraneous particle mixing with the glue.

2.1.2 The assembly jig shall be thoroughly cleaned of any dust using a brush before taking up assembly.

2.1.3  One rail piece of minimum. 4 m length shall be used for fabricating one glued joint.

2.1.4 The rail piece meant for fabrication of glued joints shall be straight and shall be ultrasonically tested before issue to the manufacturer.

2.1.5 The rail piece shall be cut in the middle with a rail cutting machine. It shall be ensured that the cut is square and the rail ends are square, plane and smooth. Since rail pieces taken from two separate rails are likely to have variations in profile, it is, therefore, necessary that rail pieces out from the same rail are jointed together at the cut-end for fabrication of the Joint, For this purpose, just before cutting a rail-piece, necessary marking  such as A-A' Or 1-1' etc) shall be put on the adjoining cut-ends with indelible paint and it shall be ensured that the ends with  corresponding mark only are jointed together,

2.1.6 The edges of the rail-ends of the two pieces at the out shall be finished smooth with a flat file. All burrs shall be removed,

2.1.7 Holes in rail pieces shall be drilled at locations following the relevant drawing with a precision drill using jigs to ensure accuracy. It shall be-ensured that the holes drilled are not skew.

2.1.8 The burrs around holes shall be removed. The edges of the drilled holes shall be chamfered using the chamfering tools of the type shown in Figure-1.

2.1.9 The fish-plates shall have correct profile as per drawing so that contact with rail on the fishing surfaces and web is proper. Drilling of holes in fishplates shall be done by a precision drill using jigs. The edges of drilled holes shall be cleaned of burrs. It shall be ensured that the holes drilled are not skew.

2.1.10 The markings of rail designation, rolling details etc, occurring in the zone of contact of rail and fishplates, shall be ground with a grinder so as to merge with the parent profile/contour. be, perfectly aligned both laterally and vertically. The two rails shall then-be held firmly in position by clamps. The distance between two rail ends shall be marginally more than the thickness of the end-post to be used to enable insertion of the end-post.

2.3,2 The application of glue shall be commenced only when the finished mils and  fishplate have been properly cleaned & have dried completely.

2.3.3 The resin and the hardener shall be mixed as per supplier's instructions in a suitable container. The constituents shall be thoroughly mixed to get a homogenous mixture (hereafter called as 'glue'). The glue shall be used within its pot life as prescribed by the supplier.

2.3.4 A thick layer of the glue shall-be applied on Kittling surfaces of the fishplates simultaneously by two teams of workmen.

2.3.5 One piece-of clean-glass cloth carrier shall be placed on the fishplates and evenly pressed so that the glue squeezes out through the glass cloth. The oozing glue shall be uniformly spread over, A layer of glue shall then be applied on the inside of the insulating liners followed by their placement on the glued glass-cloth carrier on the two fishplates.

2.3.6 A layer of glue shall then be applied on the outside of the insulating liners and a clean piece of glass cloth carrier shall be laid. The oozing glue shall be uniformly

2.3.7 Glue shall be applied to both the faces of the end-post, before placing it between the two rail ends. Adequate pressure shall then be applied by using screw clamps at the rail ends so that no gap is left between the end-post and the rails.

2.3.8 In case of glued joint with 6 mm thick end post, the insulating bushes duly dipped in glue shall be placed in the rail holes. The bonding surfaces of the rails shall then be coated with a layer of glue and the fishplates made ready as described in paras 2 3.4 to 2.3.6 shall be placed in position in contact with the rail web. In case of glued joint with 10 mm thick end post, the bonding surfaces of the rails shall be coated with a layer of glue and the fish plates made ready as per para 2.3.1 to 2.3.6 are to be placed in position in contact with the rail web. The insulating sleeves duly dipped in glue shall I hen be inserted in the joint holes and subsequently bolls lo be inserted for tightening to the required boll tension.

2.3.9 Bolts, washers and nuts shall then be placed in position and lightened with a torque-wrench. The torque shall be increased gradually on all the bolls in stages of 35 kg-m per bolt. Care shall be taken to tight inner bolts first and the outer bolts. Finally, all the bolts shall be tightened with a torque of 105 kg-m.

2.3.10 About 20 minutes after the initial tightening of bolts, the bolts shall be re-tightened with a torque wrench until a torque of 105 kg-m is attained.



3.0 All the facilities for carrying out stipulated tests on the glued joints should be available at the manufacturing site.

3. Lot size;

50 joints or pail thereof shall form the lot for the purpose of testing and inspection of the joints. :

3.2 Dimensional check

3.2.1 Every fabricated/assembled joint shall be checked for vertical and lateral alignment with I m long straight edge. The tolerances permitted shall be as under:

(i) Vertical alignment- Variation at the joint shall be within +1 mm and -0 mm measured at the end of 1 m straight edge placed at the top of rail head.

(ii) Lateral alignment- Variation at the joint shall not be more than + 0.5 mm measured at the centre of 1 m straight edge placed along the gauge face.

3.2.2  All the other tests shall be carried out only if the joints are dimensionally satisfactory.


Each joint shall be subjected to insulation resistance test in dry condition. A meggering voltage of 100 V DC shall be applied across the joint The value of the insulation resistance shall not be less than 25 megaohms.


3.4.1 Only if the joints are found satisfactory in dimensional check (para 3.2) and insulation resistance test in dry condition (para 3.3), the pull-but test shall be conducted.

The pull out test shall be conducted by suitably gripping the two rail pieces of the joint and subjecting the joint to axial tension. One method of conducting the lest is to hold one end of the glued joint with the help of fishplates as fixed end. The other end of the glued joint is held to a moving frame with the help of a wedge inserted in slots cut in the glued joint through the moving frame brackets. The arrangement is shown in figure 2. The other method of conducting the test is to hold the glued joint with the help offish plates at both ends of the testing frame. One end of the testing frame remains fixed and the other is moved with the help of two hydraulic  jacks operated simultaneously the arrangement is shown in figure 3. Manufacturer can adopt any other method also with prior Approval of RDSO

3.7.2 The pull out tested joints shall be dismantled soon after the inspection. Fishplates may be re-used in subsequent fabrications if their condition is satisfactory


Each joint of the rejected lot shall be marked with red paint over at least 30 cm length at both ends.


Records in respect of fabrication of glued joints should be maintained in the performae as given in Annexure G.

4.3.4 As in the case of ordinary insulated joints, the metal burrs/flow at the ends of the rails shall be removed from time to time to avoid short-circuiting. The burrs /flow shall be removed skillfully avoiding damage to the end-post.

4.3.5 It shall be ensured that live cinders which may damage glued joints' are not dropped in the vicinity of such joints.


Normally no relative movement shall occur between fails and Fishplates at the glued joint. In case, failure of the joint occurs by separation of the rail/fishplates surfaces with consequent relative movement, the damaged glued joint may be replaced as early as possible by a new joint.


4.4.1 The damaged glued joint removed from the track shall be stripped off the glue to reclaim fishplates to the extent possible. This work is best done in a Workshop. For this purpose, the glued joint shall be heated by a blow lamp to a temperature of over 200 deg. C. As soon as the glue clinging to the threads of fishbolts becomes thin, , the nuts shall be loosened and fishbolts shall be pushed out. A cheisel shall be inserted between the rail and the fishplate and with the help of gentle and careful blows of a hammer, the fishplates shall be removed.

4.4.2 The fish plates shall be  cleaned of glue dried and kept in stock for reuse if required after ascertaining that there is no physical damage.

4.4.3 Released rails, if worn out, may be disposed off as scrap as per extant practice.

A. 9.2 If the results of testing are not found satisfactory as per specifications, the firm will be required to improve upon the technique of production.

A. 9.3 Drawings and specifications of  the glued joints are priced documents and may be obtained from Director General (Wagon), RDSO, Lucknow either on cash payment at the counter or by VPP on request.

A. 9.4 After approval of test samples, the firm shall be brought on the provisionally approved list of manufacturers of glued joints for the particular drawing and al^N concerned shall be advised.

A. 9.5 For being considered for approval for bulk supply, the firm is required to establish QUALITY ASSURANCE PROGRAMME (QAP) as per the pro forma given in annexure F, and its satisfactory implementation in addition lo manufacture of a minimum number of glued joints as specified by RDSO.

A. 9.6 Based on the satisfactory & consistent quality of the firm's product, proven performance and successful implementation of QAP, the firm will be considered .for inclusion in I lie approved list of manufacturers.

A. 9.7  The approval shall be required to be renewed alter a particular period as per the terms of the letter of approval and it shall be firm's responsibility lo approach RDSO at least six months in advance for renewal of approval otherwise the approval is liable lo lapse.