Magnetic vibratory screen clamping

• US 8,312,995 B2
• Filed: 05/24/2010
• Issued: 11/20/2012
• Est. Priority Date: 11/06/2002
• Status: Expired due to Term

• Current Assignee: National Oilwell Varco LP (NOV, Inc.)
• Original Assignee: National Oilwell Varco LP (NOV, Inc.)
• Inventors: Dufilho, Paul, Scott, Eric
• Primary Examiner(s): Matthews, Terrell
• Application Number:
  US12/785,735
• Publication Number:
  US 20100235002A1
• Time in Patent Office: 911 Days
• Field of Search: 209/555, 209/315, 209/311
• US Class Current: 209/315
• CPC Class Codes: B01D 33/0315 arranged for inward flow filtration
• CPC Class Codes: B01D 33/0376 supported
• CPC Class Codes: B01D 33/37 in parallel connection
• CPC Class Codes: B01D 33/722 containing fixed liquid displacement elements or cores
• CPC Class Codes: B01D 33/76 for discharging the filter cake, e.g. chutes
• CPC Class Codes: B07B 1/42 Drive mechanisms, regulating or controlling devices, or balancing devices, specially adapted for screens
• CPC Class Codes: B07B 1/46 Constructional details of screens in general; Cleaning or heating of screens
• CPC Class Codes: B07B 13/16 Feed or discharge arrangements
• CPC Class Codes: B07B 13/18 Control

Abstract

Methods for automatically controlling a vibratory separator for processing drilling fluid are disclosed. The methods include introducing material to a vibratory separator, and sensing with a sensor apparatus a state parameter indicative of operation of the vibratory separator and providing a signal indicative of a value of the state parameter to a control apparatus. Then, with the control apparatus, automatically controlling the vibratory separator based on the level of the state parameter.

Claims

1. A method, comprising:

vibrating a basket assembly of a vibratory separator by accelerating said basket assembly with a vibratory motor apparatus that is operatively coupled to said basket assembly;

sensing acceleration of said basket assembly with a sensory apparatus that is operatively coupled to said basket assembly;

sending a signal representing said sensed acceleration from said sensory apparatus to a control apparatus;

adjusting acceleration of said basket assembly with said control apparatus based on said signal representing said sensed acceleration;

energizing an electro-magnetic clamp apparatus to thereby releasably secure at least one screen to at least one respective screen support in said basket assembly; and

de-energizing said electro-magnetic clamp apparatus to thereby release said at least one screen assembly from said at least one respective screen support.

2. The method of claim 1, wherein energizing or de-energizing said electro-magnetic clamp apparatus comprises sending a temporary electric pulse signal to said electro-magnetic clamp apparatus.

3. The method of claim 1, wherein energizing said electro-magnetic clamp apparatus comprises energizing said electro-magnetic clamp apparatus from an un-magnetic state to a magnetic state so as to thereby clamp said at least one screen to said at least one screen support.

4. The method of claim 1, wherein de-energizing said electro-magnetic clamp apparatus comprises de-energizing said electro-magnetic clamp from a magnetic state to an un-magnetic state so as to thereby release said at least one screen from said at least one screen support.

5. The method of claim 4, wherein, after de-energizing said electro-magnetic clamp apparatus, said electro-magnetic clamp apparatus remains in said un-magnetic state until receiving an temporary electric pulse signal that energizes said electro-magnetic clamp apparatus.

6. The method of claim 1, wherein adjusting acceleration of said basket assembly comprises controlling, with said control apparatus, a drive apparatus that is operatively coupled to said vibratory motor apparatus so as to selectively drive said vibratory motor apparatus at a selected speed and thereby apply a desired acceleration to said basket assembly to facilitate treatment of a material mixture introduced to said at least one screen of said basket assembly.

7. The method of claim 6, wherein controlling said drive apparatus comprises controlling a variable frequency drive.

8. The method of claim 1, wherein sensing acceleration of said basket comprises sensing acceleration of said basket with an accelerometer.

9. The method of claim 1, further comprising driving said vibratory motor apparatus so as to boost acceleration of said basket assembly and controlling said electro-magnetic clamp apparatus by sending at least one temporary electric pulse signal from a controller device to said electro-magnetic clamp apparatus so as to energize said electro-magnetic clamp apparatus.

10. The method of claim 9, further comprising boosting acceleration of said basket assembly to a preselected acceleration value when a flow rate of a material mixture introduced to said basket assembly is increased above a predetermined flow rate.

11. The method of claim 1, further comprising adjusting acceleration of said basket assembly over a continuous range.

12. The method of claim 1, wherein said signal representing said sensed acceleration is indicative of an actual basket assembly acceleration, the method further comprising comparing said actual basket assembly acceleration to a desired basket assembly acceleration value and controlling operation of said vibratory motor apparatus until said actual basket assembly acceleration substantially matches said desired basket assembly acceleration value.

13. The method of claim 1, further comprising adjusting a tilt angle of said basket assembly so as to tilt said basket assembly to a fully uphill basket tilt position and thereafter adjusting acceleration of said basket assembly so that a level of a material mixture in said basket assembly is decreased.

14. The method of claim 1, further comprising controlling said vibratory motor apparatus so that acceleration of said basket assembly remains substantially constant under changing conditions of a flow of a material mixture introduced to said basket assembly.

15. The method of claim 1, further comprising introducing a flow of a material mixture comprising drilling fluid and solids to said basket assembly of said vibratory separator and treating said material mixture with said vibratory separator so as to separate at least a portion of said solids from said material mixture.

16. The method of claim 1, further comprising:

sensing a level of a material mixture in said basket assembly with a level sensing apparatus operatively coupled to said vibratory apparatus;

sending a signal representing said sensed level of said material mixture from said level sensing apparatus to said control apparatus; and

controlling said vibratory motor apparatus with said control apparatus based on said signal representing said sensed level of said material mixture.

17. A method, comprising:

introducing a flow of a material mixture comprising drilling fluid and solids to a basket assembly of a vibratory separator, said basket assembly comprising at least one screen that is supported by at least one respective screen support mounted therein;

vibrating said basket assembly so as to separate at least a portion of said solids from said material mixture, wherein vibrating said basket comprises accelerating said basket with a vibratory motor apparatus that is operatively coupled thereto;

sensing acceleration of said basket assembly with a sensory apparatus that is operatively coupled to said basket assembly and sending a signal representing said sensed acceleration from said sensory apparatus to a control apparatus;

increasing acceleration of said basket assembly when said sensed acceleration is less than a preselected acceleration, wherein increasing acceleration of said basket assembly comprises controlling with, said control apparatus, a force applied to said basket assembly by said vibratory motor apparatus; and

sending an energizing temporary electric pulse signal from a controller device to an electro-magnetic clamp apparatus, wherein said energizing temporary electric pulse signal energizes said electro-magnetic clamp device to a magnetic state so as to releasably secure said at least one screen to said at least one respective screen support.

18. The method of claim 17, further comprising:

decreasing acceleration of said basket assembly when said sensed acceleration exceeds said preselected acceleration by controlling, with said control apparatus, a force applied to said basket assembly by said vibratory motor apparatus; and

sending a de-energizing temporary electric pulse signal to de-energize said electro-magnetic clamp apparatus, wherein said de-energizing temporary electric pulse signal de-energizes said electro-magnetic clamp device from said magnetic state to an un-magnetic state so as to thereby release said at least one screen from said at least one respective screen support.

19. The method of claim 17, wherein increasing acceleration of said basket assembly comprises controlling a drive apparatus that is operatively coupled to said vibratory motor apparatus so as to selectively drive said vibratory motor apparatus at a selected speed, said drive apparatus comprising a variable frequency drive.