Mill-right system

1. An apparatus for improving drilling performance of a coiled-tubing system during milling, wherein the coiled-tubing system includes an injector coupled to a pair of hydraulic motors and a drill bit coupled to a length of coiled tubing that is movable coupled to the injector, the apparatus comprising:

at least one closed loop electro-proportional valve coupleable to the pair of hydraulic motors;

at least one solenoid valve; configured to enable the apparatus;

at least five cartridge valves coupled to the solenoid valve;

at least one small pressure filter configured to filter a supply of hydraulic fluid within the apparatus; and

at least three pressure feedback devices;

and a motion controller coupled to the closed loop electro-proportional valve, to the at least three pressure sensors, and to a human-machine interface;

wherein software is configured to receive and transmit data between the closed loop electro-proportional valve, the motion controller, the at least three pressure sensors, and the human-machine interface;

wherein the apparatus performs at least one selected from the group consisting of controlling a weight on a drill bit, controlling a rate of penetration of the drill bit, and controlling a differential pressure.

2. The apparatus of claim 1 wherein the closed loop electro-proportional valve controls the hydraulic motors while milling.

3. The apparatus of claim 1 wherein the at least five cartridge valves isolate the apparatus.

4. The apparatus of claim 1 wherein the at least three pressure feedback devices are transducers mounted remotely from a manifold, and wherein the apparatus is housed within the manifold.

5. The apparatus of claim 1 wherein a manifold is mounted to an injector frame of the injector, wherein the apparatus is housed within the manifold.

6. The apparatus of claim 1 further comprising bulkhead provisions for pressure supply and low pressure return for the control manifold; a pressure filter to protect against contamination; at least one small accumulator; plumbing remote mounted from manifold; a wiring harness from a human-machine interface to a injector junction box; and wiring from the injector junction box to devices.

7. A method of improving drill performance of a coiled-tubing system during milling, wherein the coiled-tubing system includes an injector coupled to a pair of hydraulic motors and a drill bit coupled to a length of coiled tubing that is movable coupled to the injector, using the apparatus of claim 1 , the method comprising:

wherein the rate of penetration of the drill bit is controlled;

wherein the weight on the drill bit is controlled;

wherein the differential pressure across a well head is controlled;

wherein the drill bit is a milling drill bit;

wherein an output to the proportional valve is adjusted to provide control of the pair of hydraulic motors.

8. The method of claim 7 further comprising moving the drill bit to a bottom of a hole.

9. The method of claim 7 further comprising setting maximum values for the weight on the drill bit, the rate of penetration, and the differential pressure.

10. The method of claim 9 wherein the apparatus shuts down if any of the maximum values are exceeded.

11. The method of claim 7 wherein controlling the weight on the drill bit, controlling the rate of penetration of the drill bit, and controlling the differential pressure are performed simultaneously.

12. The method of claim 7 wherein two of the group consisting of controlling the weight on the drill bit, controlling the rate of penetration of the drill bit, and controlling the differential pressure are activated simultaneously.

13. The method of claim 7 wherein the apparatus is installed on the injector.

14. The method of claim 7 wherein an operator selects a milling mode with the human-machine interface.

15. The method of claim 7 wherein the rate of penetration of the drill bit is controlled by adjusting a flow rate by adjusting a swash plate in the hydraulic motors to allow an injector drive chain to speed up.

16. The method of claim 7 wherein a hydraulic pressure is adjusted to control the weight on the bit.