Components of Hook-up Systems.

These are some materials that may be used for construction of surface safety valve network or hook-up,viz:
1.kerotest needle valve (1/2''x90degree)
2.pressure regulator (1/2x1/4)
3.water drain valve (1/4x1/2)
4.0-25psi pressure guage
5.Regulator valve
6.Nipple 2''x36''
7.Flowline pipe 6''
8.0-5000psi pressure guage
9.Bracket 2''x4''
10.u-valve
11.kerotest needle valve 45x90 (degree)x1/2
12.sigma valve (1/2''x1/4'').
13.Tee joint.1/4''
14. P-pilot 1/2''x1/4''
15. weldolet. 2''x1/2''
16.Dust protector 1/4''
17.Fuse plug
18.Stainless steel connector,1/2''
19.U-valve indicator
20.Pressure relief valve
21.Instrument line1/4''
22.Elbow1/4''
23.Instrument connector 1/2''
24.Flowline flange 6''x14''x36
25.Sigma valve control 1/4''x1/2''
26.Instrument air.
27.Coupling 1/2''x6''
28.Bull plug1/2''x2''

Field Observation of Well Characteristics

This observation is made based on series of activities that were performed in various fields.It will be  interesting to understand that well calibration could be affected by what is called surges. Surges occurs due to the kinetic velocity or energy level of the fluid.The crude oil reservoir is drilled several dept away from the surface and the velocity of crude or oil/gas seem to be affected by this factor.The surging or turbulence effect in the overal calibration process can also lead to a fault, thereby tripped the contromatic system.Sometimes surging in some of the wells are continous while in others, it may be  intermittent and also has lots of effect in the overal operation. The particles that associates with the fluid have some corrosive effect in the mechanical instrumentation materials and the instrument sensors.It is therefore expected that adequate monitoring or routine maintenance be adopted, because it will enhance and provide the necessary information on the condition of the contromatic and the well upkeep. 

The Safety Gate valves components.

1.Hard hand wheels assy.                   24.Spring

2.Bearing cap                                     25.Pin used only on valves under 10,000 psi wp                                                                               

                                                                         

                                                           26.Body

3.Grease fitting                                   27.Name plate

4.O-Ring                                             28.Seal ring 

5.Bearig race                                       29.Bonnect

6.Thrust bearing.                                 30.Check valves,(10,000 psi wp and above) 

7.O-Ring.                                             31.Grease fitting.

8.Stem adapter                                     32.Gaskets

9,Packing gland                                   33.Body bushing 

10.Stem Ring                                       34.Guide

11.Nut                                                  Note: w.p= working pressure,where pressure= force per unit                                                                                       area(N/mm)

12.Stem packing                                                       

13.Stud

14.Stem

15.Gate

16.Retainer plate

17.Seat ring

18.Seal ring

19.Dog

The safety of offshore/onshore field operation/ calibration of wells.

In active participation on offshore and onshore operations, the following safety processes are essential.
1.Ensure that you know the number of items to take along in each operation.
2.Do not forget your communication radio and each operating field activity or platform frequency.
3.while carrying out well calibration on a surging well,make sure you ascertain the surging differential of low and high pressure lines.

4.All items must/should be arrange at a postion/location where it will be easily accessible for             operation.

5.Do not rush or hasten over your plans on the job,but should carefully handle your tooling.
6.Inform your field Supervisor when you are ready for the operation.
7.Radio the production platform on your arrival at the site and after the day's job.
8.Always record your shut-in time and opening of well for production interval.
9.Always pass through the front side of the helicopter to avoid being injured by the fan on the side.
10. Do not step on the rubber stand of the helicopter, a wooden plank is provided for stepping.
11.While in the helicopter remember to put your life jacket and ear muffle and off your phone
     or handset.
12.Do not arrange your working loads on the helideck.
13.Take suitable rope to hold your head-hat in position if it does not have such an attachment.
14.Do not jump steps either up or down. 

How a well calibration is streamlined.

 In most well calibration there are parameters that is expected to be presented to the oil field manager,to enable him have some insight of the well.
A. The name of the field where the activity was peformed must be mentioned and the well number.
The parameters obtained shall be thus:
1.Upstream pressure u/p =2750psi
    Downstream pressure d/s=390psi
    observation: found flowline valve faulty.
Maintenance:re-connected fault.
Re- calibrated p-pilot
                             H= 500psi
                              Lo=130psi
Shut-in-interval = 08.30 - 11.30Hrs
well no. ok. no.4. etc

2.   u/s=3000(psi)   
       d/s=530(psi)
 observation=malfunctioned p-pilot and instrument guage;
 maintenance=replaced p-pilot.
Recalibrated p-pilot needle
                     H=800(psi)
                      L=350(psi)
Shut-in- interval 14.00 - 15.00Hrs. etc 

MODE OF OPERATION

The safety valves system is designed to accomodate stainless steel tubing connections interwoven to form a closed loop. The instrument air from the regulator to the supply inlet of the sigma valve keeps the u-valve permanently open and maintain a pressure in the pilot.The pilot has a calibrated range of low and high and to obtain each parameter for calibration,the flowline pressure has to be determined. Note that the high pressure range is obtained in the wellhead through the crown valve,whereas the low pressure of the well is obtained through the wing valve of the flowline.These classification as low and high  are sometimes refer as downstream and upstream pressure,depending on the operators.Therefore the pilot is calibrated at 75% of the flowline pressures both for low and high, however any variation arising from flow causes a bleed off pressure from the sigma valve.The u-valve is actuated by this variation which the p-pilot transduced.This automatically close the gate of the u-valve actuator,thereby shutting off the flowline.The plug is also for safety purpose,and its action occurs when there is risk of fire in the well.As the temperature of gas and pressure increases. the lead in the fusible plug will met and creates a vent for pressure escape; and automatically the u-valve will be actuated thereby close or shut-in the flow.

Wellhead protective devices.1

3.Sigma Valve:The sigma valve basic function is to bleed off instrument gas or block it depending on  the prevailing circumstance or situation.The signal is tranduced by the sensor (p-pilot),which has a supply inlet and two way outlet to the sigma valve and the u-valve which consist of gasket,plunger,and spring.
4.Fusing Plug:The fusing plug is a mechanical elbow filled with lead and acts as fire safety device because the melting point of lead is less than the ignition temperature of oil/gas.