FAQs

Ductile Iron Pipe

1. Can I use restraint gaskets in above ground applications?

Restraint gaskets are not recommended for use above ground. Restraint gaskets provide a friction restrained joint and the long-term effect of cyclical movements can be gradual joint separation to the point that the seal on the gasket bulk is compromised.  Sources of cyclical movements include vibration as may be found on bridge crossings.

2. How does the Restrained Joint System compare with thrust blocks?

In most situations the cost of constructing concrete anchor blocks is similar to the cost of restraint gaskets. The saving is in the speed that restrained joint pipelines can be installed and tested. Space savings can also be a big factor.

3. Why do we sleeve DICL pipe?

Polyethylene sleeving provides corrosion protection in aggressive soils by creating a passive uniform environment around the pipe and limiting oxygen exposure.

4. How long are DICL pipes?

Hydrotite pipe has a 5.7 metre effective laying length.

5. What is the lead time for supply of DICL pipe?

Generally pipes can be supplied ex stock, but can be 1-2 months for large projects.

6. Are DICL pipe and fitting ends compatible with PVC?

Yes, if Series 2 uPVC to AS1477.

7. How is DICL pipe joined?

RRJ or flanged or by couplers at cut-ins or terminations.

8. What do I do with a leaking joint?

Check that a gasket has been installed; check joint deflection, correct deflection angle if necessary. If still leaking, drum the joint under pressure to dislodge grit. If still leaking notify Hygrade Products. Claims of faulty product are subject to in situ inspection by Hygrade Products.

9. Does the direction the sockets face in rubber ring joint pipelines matter?

No.