Fitting Instructions Viking Johnson Unfitted Stepped Couplings

File - VJSteppedCoupling_Unfitted.doc Page 1 of 2 Form 2003A 06/00

These fitting instructions apply to Viking Johnson Unfitted Stepped Couplings; i.e. the coupling components are supplied unassembled.

1 Viking Johnson Unfitted Stepped Couplings come in three configurations (shown in Fig 1) with the selection being a function of the difference in outside diameter of the two pipes.

a) Expanded Sleeve b) Fabricated Sleeve c) Make-Up-Ring Sleeve Also known as No-Bolt Type.

Fig 1. Configurations For Viking Johnson Stepped Couplings.

2 Examine the pipe ends and ensure they are round, smooth, free from bulges, dents and score marks and within the specified tolerances for that material, e.g. for Steel BS534:1990:Section 14. Weld beads must be ground flush, maintaining correct surface profile. Ensure that pipe ends are free from scale, rust, or any loose debris or other surface defect that may affect coupling performance.

3 Check grade of gasket is suitable for conveyed medium.

4 Align pipe to be laid with pipe already in position, taking care that pipe ends are concentric, adjusting support or trench bed as necessary.

5 Identify the larger pipe. Identify the larger end of the coupling sleeve and corresponding gaskets and end ring.

6 To aid installation, mark both pipe ends at a distance equal to or greater than half the overall assembled width of the coupling. Place the end rings over their respective pipe ends with the gasket chamber facing the joint between the two pipes. Lubricate the gaskets thoroughly with Viking Johnson Lubricant and stretch each one onto the respective pipe end with the thicker or vertical end towards the end ring.

7 Slide the centre sleeve fully onto the smaller diameter pipe, with the larger end of the sleeve facing the pipe end. Bring the free pipe towards the pipe already in position and adjust the setting gap between the two pipe ends as necessary, - see table below. If in doubt contact Viking Johnson Technical Support.

Typical Pipe Diameter Range Setting Gap

Expanded & Fabricated Sleeve Make-Up-Ring

Section Min. Max. Min. Max.

sizes 300mm (12) to 900mm (36) LO2 25mm (1) 50mm (2) 25mm (1) 50mm (2)

sizes 900mm (36) to 1800mm (72) YF2 / A2E 38mm (1) 76mm (3) 25mm (1) 50mm (2)

Setting Gap Table

Fitting Instructions Viking Johnson Unfitted Stepped Couplings

File - VJSteppedCoupling_Unfitted.doc Page 2 of 2 Form 2003A 06/00

8 Using marks made at step 6 slide the centre sleeve until it is centrally positioned over the pipe ends.

9 Bring each gasket forward into the gasket chambers of the centre sleeve (the end rings may assist in this operation).

10 Bring the end rings into position, which for the different configurations is as follows :-

1. Expanded or Fabricated Stepped Couplings (Types a and b).

Line up the bolt holes in the two end rings and fit all the bolts in from the same side, ensuring that the D at the neck is correctly located in the end ring holes. Fit the washers and nuts finger tight.

2. Make-up-Ring Sleeve Stepped Couplings (Type c).

Line up the holes in the end ring with the studs on one side of the centre ring, fit the washers and nuts finger tight. Repeat the operation with the end ring on the other side.

11 For expanded and fabricated sleeve stepped couplings tighten diametrically opposed bolts giving the nuts one or two turns at a time to draw up the end rings evenly. The bolts must be thoroughly tightened to the figures given below, working around the coupling as many times as necessary. On completion, radial gap between pipe and coupling should be even all the way round. Rubber may be seen to extrude into the gap.

For Make-up-Ring sleeve stepped couplings the above operation is repeated on both sides of the fitting, tightening the studs to the required bolt torque as given below.

NOTES

A Standard Viking Johnson stepped couplings do not prevent pipe pull out. Adequate external restraint is essential.

B Adequate measures must be taken to anchor the stepped coupling and prevent it from moving under pressure along the smaller diameter pipe. This is due to pressure forces from the reduction in diameter and is especially critical for large diameter changes and/or high pressures.

C When installing Viking Johnson Stepped Couplings on GRP pipe and certain AC pipes a reduced bolt torque is required consult Technical Support for further advice.

Stud / Bolt Torque

Size lbf.ft Nm Viking Johnson 46-48 Wilbury Way Hitchin Hertfordshire SG4 0UD

M12 40 50 55 65 Head Office Technical Support

M16 70 90 95 120 Tele +44(0)1462 443322 +44(0)1462 443322

Stud / Bolt Torque Table. Fax +44(0)1462 443311 +44(0)1462 443311

E-mail info@vikingjohnson.com