Installation of cured in place liners with dual gland air inversion and steam cure apparatus
View Patent ↗Installation of a flexible cured in place liner by inverting the liner with air and curing the liner with steam introduced through a perforated lay flat hose without deflating the liner between the inversion and cure. The installation is performed with an apparatus having two independently operable glands with at least one fluid inlet port installed on the line downstream of the second gland liner. As the liner reaches the distal end of the conduit to be lined, it enters a sample and porting pipe with an exhaust pipe gland and exhaust pipe and it is pierced by a rigid porting tool. Steam is then introduced into the lay flat hose to cure the resin and is exhausted through an exhaust hose connected to a controllable exhaust pipe. After curing steam is replaced with air to cool the liner, the ends are cut to restore service through the host pipe.
1. A method for inverting a liner into an existing conduit, comprising:
placing a flexible tubular liner into an installation apparatus having a first gland and a second gland downstream and spaced apart from the first gland;
securing an end of the liner to the apparatus upstream of the first gland;
inverting the liner through the apparatus past at least one gland;
positioning a fluid inlet port in the inverted portion of the liner downstream of the at least one gland;
closing one of the glands with the fluid inlet port on the downstream side thereof;
introducing a pressurized inversion fluid into the inverted portion of the liner through the fluid inlet port; and
allowing the liner to invert in response to the fluid introduced through the fluid inlet port,
wherein the fluid inlet port is a first fluid inlet port, the method further including positioning the first fluid inlet port in the inverted liner downstream of the second gland and positioning a second fluid inlet port between the two glands.
2. The method of claim 1 , wherein the inlet port is installed prior to securing the liner to the apparatus.
3. The method of claim 1 , wherein a portion of the liner is inverted prior to being placed into the apparatus.
4. A method as set forth in claim 1 wherein the liner comprises a resin impregnated therein and wherein allowing the liner to invert comprises inverting the liner from a first access point of an existing pipeline to a second access point of the pipeline by introducing the pressurized inversion fluid into the liner through the first fluid inlet port while the second gland is closed, the method further comprising:
closing the first gland;
opening the second gland; and
introducing a curing fluid into the inverted liner through the second fluid inlet port to cure the resin in the liner.
5. The method of claim 4 , further comprising
attaching a hold back strap to an end of the liner opposite the end that is secured to the installation apparatus,
wherein closing the first gland comprises engaging the hold back strap with the first gland.
6. The method of claim 5 , including attaching an end of a lay flat hose to the same end of the liner as the hold back strap.
7. The method of claim 6 , wherein the end of the lay flat hose that is attached to the liner is closed.
8. The method of claim 6 , including attaching the lay flat hose to the second fluid inlet port.
9. The method of claim 8 , wherein attaching the lay flat hose to the second fluid inlet port includes:
cutting the lay flat hose upstream from the second gland;
attaching one end of an elbow to the cut end of the lay flat hose; and
attaching the other end of the elbow to the second fluid inlet port.
10. The method of claim 8 , wherein attaching the lay flat hose to the second fluid inlet port, includes:
cutting the lay flat hose upstream from the second gland;
feeding the cut end of the cut end of the lay flat hose through the second fluid inlet port;
inserting a relatively stiff bendable tubular rigid sleeve with a flared end into the cut end of the lay flay hose to make the cut end of the lay flat hose resistant to kinking;
banding the lay flat hose to the tubular portion of the sleeve; and
inserting the lay flat hose and tubular portion of the sleeve into the second fluid inlet port so the flared end of the sleeve prevents the sleeve from being pulled into the liner through the second fluid inlet port.
11. The method of claim 6 , wherein the lay flat hose is perforated along its length to distribute curing fluid along the length of the interior of the inverted liner.
12. The method of claim 6 , wherein closing the first gland comprises closing the first gland after a connection connecting the lay flat hose and hold back strap to the liner passes therethrough and opening the second gland comprises allowing the connection to pass through the second gland while it is open.
13. The method of claim 1 , including the step of forming an exhaust port in the liner at the downstream end of the inverted liner after the inversion is complete without allowing the inverted liner to deflate.
14. The method of claim 4 , wherein the inversion fluid is air and the curing fluid is steam.
15. A method for inverting a liner into an existing conduit, comprising:
placing a flexible tubular liner into an installation apparatus having a first gland and a second gland downstream and spaced apart from the first gland;
securing an end of the liner to the apparatus upstream of the first gland;
inverting the liner through the apparatus past at least one gland;
positioning a fluid inlet port in the inverted portion of the liner downstream of the at least one gland;
closing one of the glands with the fluid inlet port on the downstream side thereof;
introducing a pressurized inversion fluid into the inverted portion of the liner through the fluid inlet port;
allowing the liner to invert in response to the fluid introduced through the fluid inlet port; and
forming an exhaust port in the liner at the downstream end of the inverted liner after the inversion is complete without allowing the inverted liner to deflate.