Dual gland air inversion and steam cure of cured in place liners
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. An air inversion and steam cure apparatus for installing a resin impregnated cured in place pipe liner, the apparatus comprising:
a frame having an entry opening for securing a free end of the liner thereto;
a first selectively operable gland mounted to the frame at a point spaced apart from the entry opening to allow a flattened inverted liner to pass when open and to engage the liner to form a fluid tight seal about the liner passed therethrough when closed; and
a second selectively operable gland mounted to the frame downstream from the first gland to allow the liner to invert therebetween when open and to rigidly engage the liner to form a fluid tight seal about the liner passed therethrough when closed, the frame between the first and second gland being open to allow access to the liner passed therethrough;
each of the first and second glands having a first and a second rigid gland member with at least one of the gland members selectively displaceable relative to the other gland member to vary a gap between the gland members of the respective gland, the rigid gland members of the first gland having a compressible material mounted on opposing faces of the gland members, the rigid gland members of the second gland having opposed rigid metal contact surfaces adapted to contact the liner while maintaining a selectively adjustable gap defining a space for the liner between the rigid metal contact surfaces; and
a gap adjustment device comprising structure positioned for operative engagement by the gland members of the second gland as the gap between the gland members decreases to maintain at least a minimum amount of separation between the members of the second gland.
2. The apparatus of claim 1 , wherein the gap adjustment device comprises at least one spacer positioned to prevent reduction of the gap width beyond a minimum desired gap width.
3. The apparatus of claim 1 , wherein the gap adjustment device comprises an adjustment bolt.
4. The apparatus of claim 1 , wherein the compressible material mounted on the rigid gland members of the first gland comprises a high temperature resistant compressible material.
5. The apparatus of claim 1 , further comprising motors coupled to the displaceable gland members for adjusting the gap between the gland members.
6. The apparatus of claim 5 , wherein each motor is mounted on the frame and coupled to the displaceable gland members.
7. The apparatus of claim 5 , wherein the motors comprise a pair of motors for each gland mounted on the frame at opposite ends of the respective displaceable gland member.
8. The apparatus of claim 5 , wherein the motors comprise pneumatic cylinders.
9. The apparatus of claim 1 ,further comprising linear guide bearings mounted to the frame, wherein the displaceable gland members are displaced along the linear guide bearings to vary the gap between the gland members.
10. The apparatus of claim 1 , further comprising a plurality of hooks mounted on the frame and adapted to mount the free end of the liner on the frame, the hooks being positioned adjacent the first gland so the first gland is positioned intermediate the hooks and the second gland.
11. The apparatus of claim 1 , wherein the gland members comprise metal bars.
12. The apparatus of claim 1 , wherein the gland members comprise metal tubes.
13. The apparatus of claim 1 , further comprising a plurality of hooks secured to the frame at the entry opening.