Reinforced grommet for cured in place liner
View Patent ↗Method and apparatus for forming a grommet assembly to seal and reinforce holes through a cured in place liner for securing a cable. A first grommet base having a centrally located aperture with wedge shaped grooves is positioned on one side of the hole. A barrel having two opposed sets of wedge shaped projections is inserted into the grommet base and a second grommet base is placed on the barrel and pushed towards the liner until the second base firmly contacts the top surface of the liner and compresses the liner against the first base. The wedge shaped projections on the barrel and the complimentary grooves in the central apertures of the grommet bases prevent the barrel from being pulled out of either grommet base. The end of the barrel which projects out above the second base is cut off flush with the top surface. A hydraulic press to install the grommet assembly is also disclosed.
1. A grommet for reinforcing an opening in a cured in place liner, comprising:
first and second grommet bases each having an outer surface and an opposed inner liner facing surface with a central opening extending between the two surfaces;
each grommet opening having a securement surface; and
a barrel having first and second securement surfaces adapted for engaging the securement surfaces of the grommet bases when the barrel is inserted into the central opening in the grommet bases, the first and second securement surfaces of the barrel being oriented in opposite directions such that engagement of the first securement surface with the securement surface of the first grommet base prevents nonrotational movement of the first grommet base in a first direction and engagement of the second securement surface with the securement surface of the second grommet prevents nonrotational movement of the second grommet base in a second direction which is opposite the first direction.
2. The grommet of claim 1 wherein the barrel has opposite ends and each end is sized and configured for insertion into the central opening of one of the first and second grommet bases.
3. A grommet for reinforcing an opening in a cured in place liner;
two grommet bases each having an outer surface and an opposed inner liner facing surface with a central opening extending between the two surfaces;
the opening having a plurality of circles of wedge shaped grooves, each circle of grooves having in cross-section an edge inclined with respect to the axis of the opening and an edge perpendicular to the axis, the inclined edge starting at the outer surface inclined away from the axis of the opening; and
a barrel having a first series of circular wedge shaped projections for engaging the grooves on one of the grommet bases when inserted into the opening in the grommet base and a second series of wedge shaped projections for engaging the grooves on the other grommet base when inserted into the opening in the grommet base, wherein the first series of circular wedge shaped projections has an opposite orientation with respect to the second series of circular wedge shaped projections so the first and second series of circular wedge shaped projections prevent movement of the grommet base members in opposite directions when the opening of one of the grommet bases is received on the barrel over the first series of circular wedge shaped projections and the opening of the other of the grommet bases is received on the barrel over the second series of circular wedge shaped projections.
4. The grommet of claim 3 , wherein the projections at one end of the barrel extend a distance about the length of the opening in the grommet base.
5. The grommet of claim 3 , wherein the inclined edge of the wedge shaped grooves and projections are inclined with respect to the axis of the opening in the grommet base between 10 to 80 degrees.
6. The grommet of claim 3 , wherein the inclined edge of the wedge shaped grooves and projections are inclined to the axis of the opening in the grommet base between about 40 to 70 degrees.
7. The grommet of claim 3 , where at least the barrel is a substantially rigid polymeric material.
8. The grommet of claim 7 , wherein any excess length of the barrel extending beyond the grommet bases is cut at the outer surface of the grommet bases.
9. The grommet of claim 3 , wherein the inner liner facing surface of at least one of the grommet bases has a circular groove for receiving an O-ring.
10. The grommet of claim 3 , wherein the inner facing surface of at least one of the grommet bases has an integrally formed O-ring.
11. The grommet of claim 3 , including holes formed in the outer surface of the grommet bases for securing a fastener to the liner.
12. The grommet of claim 3 , wherein each grommet base is substantially tubular with the opening at the center thereof.
13. A grommet for reinforcing an opening in a cured in place liner, the grommet comprising:
first and second grommet bases each having an outer surface and an opposed inner liner facing surface with a central opening extending between the two surfaces;
a barrel having opposite first and second ends each sized and configured for insertion into the central opening of a respective one of the first and second grommet bases; and
a securement surface on at least one of the barrel and the central openings of the first and second grommet bases, the securement surface being configured for preventing the first and second grommet bases from moving in opposite directions when the central openings of the first and second grommet bases are received on the barrel.
14. The grommet of claim 13 wherein the securement surface is on the barrel.
15. The grommet of claim 14 wherein the securement surface is on the barrel and the openings of the first and second grommet bases.
16. A grommet for reinforcing an opening in a cured in place liner, the grommet comprising:
two grommet bases each having an outer surface and an opposed inner liner facing surface, the inner liner facing surfaces each having a circular groove for receiving an O-ring;
at least one of the grommet bases including a central opening extending between the outer surface and the inner liner facing surface, the opening having a securement surface;
a barrel having a complimentary securement surface adapted for engaging the securement surface of the grommet base when the barrel is inserted into the opening in the grommet base, the securement surfaces being configured such that when the opening of the grommet base is received on the securement surface of the barrel the securement surface of the barrel permits the grommet base to move in a first direction toward the other grommet base and prevents the grommet base from moving in a second direction away from the grommet base, the second direction being opposite the first direction.
17. The grommet of claim 16 wherein each grommet base includes the central opening having the securement surface.
18. The grommet of claim 16 further comprising first and second O-rings adapted for reception in the circular grooves of the grommet bases.
19. A grommet for reinforcing an opening in a cured in place liner, the grommet comprising:
two grommet bases each having an outer surface and an opposed inner liner facing surface, the inner liner facing surfaces each having an integrally formed O-ring;
at least one of the grommet bases including a central opening extending between the outer surface and the inner liner facing surface, the opening having a securement surface;
a barrel having a complimentary securement surface adapted for engaging the securement surface of the grommet base when the barrel is inserted into the opening in the grommet base, the securement surfaces being configured such that when the opening of the grommet base is received on the securement surface of the barrel the securement surface of the barrel permits the grommet base to move in a first direction toward the other grommet base and prevents the grommet base from moving in a second direction away from the grommet base, the second direction being opposite the first direction.
20. The grommet base of claim 19 wherein each grommet base includes the central opening having the securement surface.