Apparatus for and method of monitoring a drilling installation

1. An assembly comprising:

two tubular elements;

a primary seal and a secondary seal arranged between the two tubular elements;

a seal cavity formed between the two tubular elements, the primary seal and the secondary seal; and

a seal monitoring apparatus comprising a housing and a position sensor,

the housing comprising a chamber wherein is arranged a separator, the separator dividing the chamber into a first sub-chamber and a second sub-chamber, the first sub-chamber being fluidly connected to the seal cavity and being filled with a hydraulic fluid, the separator being movable in a first direction relative to the housing so as to increase a volume of the first sub-chamber and to decrease a volume of the second sub-chamber, and in a second direction relative to the housing so as to decrease the volume of the first sub-chamber and to increase the volume of the second sub-chamber, and

the position sensor being configured to generate an electrical signal which represents a position of the separator relative to the housing.

2. The assembly as recited in claim 1 , wherein the housing and the separator are configured so that the chamber is only divided into the first sub-chamber and the second sub-chamber.

3. The assembly as recited in claim 1 , wherein the separator is a floating piston.

4. The assembly as recited in claim 1 , wherein the second sub-chamber is filled with a compressible fluid.

5. The assembly as recited in claim 1 , wherein the housing further comprises a vent port which connects the second sub-chamber to an atmosphere at an exterior of the housing.

6. The assembly as recited in claim 1 , wherein the position sensor is further configured to transmit the electrical signal which represents the position of the separator relative to the housing to a processor at a location which is remote from the primary seal and the secondary seal.

7. The assembly as recited in claim 1 , further comprising:

a conduit which is arranged through one of the two tubular elements,

wherein,

the first sub-chamber is connected to the seal cavity via the conduit.

8. The assembly as recited in claim 1 , wherein the seal monitoring apparatus further comprises a restrictor device which is configured to be activated to prevent a movement of the separator relative to the housing, and de-activated to allow a movement of the separator relative to the housing.

9. The assembly as recited in claim 1 , wherein the housing further comprises,

a port which is configured to provide a conduit from an exterior of the housing into the first sub-chamber, and

a plug or a valve which is configured to close the port.

10. The assembly as recited in claim 1 , wherein the housing is arranged to be integral with one of the two tubular elements.

11. The assembly as recited in claim 1 , wherein the seal monitoring apparatus further comprises a resilient biasing element which extends between the separator and the housing, the resilient biasing element being configured to exert a biasing force on the separator so as to urge the separator to move in the first direction relative to the housing.

12. The assembly as recited in claim 11 , wherein the resilient biasing element is arranged in either the first sub-chamber or in the second sub-chamber.

13. A drilling installation comprising:

two tubular elements;

a primary seal and a secondary seal arranged between the two tubular elements;

a seal cavity formed between the two tubular elements, the primary seal and the secondary seal; and

the seal monitoring apparatus as recited in claim 1 .

14. A method of monitoring seals in an assembly, the assembly comprising:

two tubular elements;

a primary seal and a secondary seal arranged between the two tubular elements; and

a seal cavity formed between the two tubular elements, the primary seal and the secondary seal,

the method comprising:

securing a seal monitoring apparatus to one of the two tubular elements, the seal monitoring apparatus comprising a housing which comprises a chamber wherein is arranged a separator, the separator dividing the chamber into a first sub-chamber and a second sub-chamber, the first sub-chamber being fluidly connected to the seal cavity and being filled with a hydraulic fluid, the separator being movable in a first direction relative to the housing so as to increase a volume of the first sub-chamber and to decrease a volume of the second sub-chamber, and in a second direction relative to the housing so as to decrease the volume of the first sub-chamber and to increase the volume of the second sub-chamber; and

using a position sensor to monitor a position of the separator in the housing.

15. A method of monitoring a loading of two tubular elements in an assembly, the assembly comprising:

the two tubular elements;

a primary seal and a secondary seal arranged between the two tubular elements; and

a seal cavity formed between the two tubular elements, the primary seal and the secondary seal,

the method comprising:

securing a seal monitoring apparatus to one of the two tubular elements, the seal monitoring apparatus comprising a housing which comprises a chamber wherein is arranged a separator, the separator dividing the chamber into a first sub-chamber and a second sub-chamber, the first sub-chamber being fluidly connected to the seal cavity and being filled with a hydraulic fluid, the separator being movable in a first direction relative to the housing so as to increase a volume of the first sub-chamber and to decrease a volume of the second sub-chamber, and in a second direction relative to the housing so as to decrease the volume of the first sub-chamber and to increase the volume of the second sub-chamber; and

using a position sensor to monitor a position of the separator in the housing.