壳牌公司井控手册 - Well Control Policy

1、1.WELL CONTROL POLICY STATEMENTSPolicy statements are those global directives that are considered fundamental to the way we conduct our business and operations. Under normal circumstances deviation from well control policy is not permitted without prior approval through Operating Company procedures.

2、 These Policies provide the guidelines for interpretation, selection and application of procedures.All well control operations shall be conducted in such a manner as to give highest priority to safety of personnel.The second order of priority shall be to minimise environmental impact whether this be

3、 atmospheric, terrestrial, marine or subterranean.The third order of priority shall be given to minimise losses be they loss of time, equipment or material.As a minimum, all facets of well control shall be in accordance with the relevant laws of the area of operation.The procedures in this manual ar

4、e set as a minimum standard, which must be bettered or at least equalled. Where operations are to be conducted using other procedures, dispensation must be granted by the OU Drilling Manager and the fact highlighted in the work programmeWhere operations are non-standard or hazardous drilling conditi

5、ons exist, additional safety measures shall be specified in the well programme.API standards and recommended practices shall be followed to the extent that they do not conflict with these policies.Accurate records of all operations shall be maintained, with particular attention paid to any unusual o

6、ccurrences. For pressure tests, recording charts are recommended and should be retained with other well documentation.For the purpose of well control, well specific risks shall be identified and reviewed using a structured evaluation system. Higher risk wells shall be the subject of a higher level o

7、f planning and control where modelling and other tools may be required.Well drilling, workover programmes and operational procedures shall be designed and executed to continuously maintain primary control.Primary well control during intentional underbalanced operations shall be maintained by a combi

8、nation of fluids, well bore casings and specialised pressure equipment. Specialist Well Control equipment shall be in addition to the normal BOP arrangement.1.12.Person in ChargeAll well control operations at the wellsite shall be under the direction of a pre-appointed “Person in Charge” whose respo

9、nsibilities and duties shall be clearly defined. The Person in Charge for the drilling or Well Intervention unit and deputies shall be agreed in writing between the relevant Company and Contractor Management.All well control operations shall be conducted with sufficient personnel to ensure safety an

10、d efficiency.Drills shall be carried out to achieve and maintain an acceptable performance standard. Drills shall continue until the Shell representative is confident that equipment and personnel are operating to the agreed standard. Drills may include but not be limited to Drilling, tripping, strip

11、ping, out of hole, and volumetric.The Mud Logger, Mud Engineer, Derrickman and/or Shaker Hand, and other members of the drilling team shall each keep the Driller fully informed of any indications of a potential well control situation.The decision to take immediate corrective action shall be the resp

12、onsibility of the Driller.At least two muster areas shall be established on each drilling or workover site/facility. Of these two areas, the one upwind at any given time is the safe muster area unless otherwise designated. Note: this may be because of inaccessibility, fire or other reasons.Well cont

13、rol related information shall be disseminated to all relevant personnel and contractors, as required, and well control aspects shall be regularly discussed during handovers, the weekly safety meetings, or toolbox meeting. Safety meetings with Company, rig and contractor personnel shall be conducted

14、before all well control operations. The meetings should review planned operations and contingencies.Reliable 24 hours per day radio and/or telephone communications shall be established between the well site and base supervisory personnel. An independent backup system should also be available.The Com

15、pany Rig Superintendent or equivalent e.g. Senior Well Engineer (Operations etc. at the base shall be advised of any deficiencies in BOP equipment, standards, and operating procedures.1.22.Equipment ProvidedAll operations shall be provided with the equipment as agreed in the contract, which is neces

16、sary to conduct well control operations in a safe and efficient manner.All well control equipment shall be of dimensions and pressure rating appropriate for the application. All well control equipment shall be maintained with manufacturer genuine or approved spares and shall be operated and tested i

17、n accordance with manufacturers recommended procedures.Each newly contracted drilling unit shall undergo a blowout prevention review as part of the commissioning process prior to spud of its first well and shall include:BOP equipment, controls and control unit location;Mud gas separatorKick detectio

18、n systems;BOP operating standards and procedures;BOP inspection, testing, and maintenance programme.This review is recommended to be repeated at suitable milestones during the life of the contract e.g. with a change in operational risk, before an exploration or workover campaign, particularly hazard

19、ous or tricky well etc.Where there is a risk of drilling through formations containing hydrocarbons that have the potential to flow to surface, shear rams should be installed in the BOP stack and be proven capable of shearing the drill pipe in use under no-load conditions and subsequently provide a

20、proper seal. (in use = sequentially added at surface while drilling Where shear rams are not available or not able to cut the selected drill pipe, procedures to make the well safe must be in place and regularly practised for ALL such situations.Whenever there is a risk of uncontrolled flow up the dr

21、ill string, a method of controlling flow shall be specified for each individual well operation.Adequate material, supplies and reserves to effectively deal with well control situations in a timely manner shall be available. The required quantity and quality of materials and supplies shall conform to

22、 Operating Company procedures and normally be documented in the well programme.All well casing and tubing designs shall be in accordance with the Shell Casing and Tubing Design Guide.Any new casing or liner shall undergo an integrity test before further drilling or other category of work is carried

23、out through that casing. The type of integrity test shall be specified in the well programme. In general, the casing or liner shall be pressure tested immediately after cementing (soft cement as specified in the well programme.Periodic checks shall be made to establish the kick tolerance in terms of

24、 magnitude and intensity of an influx that can be safely handled with the mud in use.aThe margin of safety (weight tolerance between the current mud weight and the shoestrength (practical consideration, andbThe risk (volume or weight tolerance and consequence of not being able to containand safely m

25、anage, and thus the choice of procedures to prevent and deal with, a kick. On drilling out each casing string, it is important to establish the formation integrity.1.32.Shallow GasAn optimal site investigation shall be conducted at a drilling location to determine the likelihood of shallow gas being

26、 present. In areas where shallow gas is deemed a possibility, consideration should be given to moving the surface location. In any case, a contingency plan shall be prepared prior to spud.Deviation surveys shall be taken to ensure that the course of the well is within the limits given in the program

27、me and that the bottom hole location is known to a degree that enables intersection by a relief well. .Any open well with exposed formation shall be monitored continuously for flow.A flow check shall normally be made whenever a drilling break is encountered.As a minimum flow checks shall be performe

28、d on all trips out of the hole:On bottomIn the shoe of the last casing stringBefore starting to pull the BHA through the BOP.When tripping, procedures shall be used to minimise swabbing and surging. In circumstances where it is suspected that swabbing may have occurred, and provided there is no flow

29、, the pipe shall be run back to bottom and bottoms-up circulated.The trip tank shall be used for the accurate measurement of mud volume changes when tripping. Trip sheets recording actual vs. theoretical volume changes shall be filled-in for each trip in and out of the hole. The trip tank should also be used for monitoring the well under static conditions i.e. logging etc.The Driller and Mu