|
 Christmas trees for oil and gas wells are intended to seal wellhead, inspect and control their mode of operation as well as for performance of process operations at pressures to 14, 21, 35, 70 and 105 МPа (2,000, 3,000, 5,000, 10,000, 15,000 psi). Manufactured of АF type where tubing is hanged in mandrel hanger, АFК type where tubing is hanged in adapter flange and АFа type having additional tubing head which provides hanging two rows of concentric tubing strings; moreover there may be either with duplicate gate valves on side outlets of Christmas tree and tubing head or not.
See Tables 1 and 2 for Christmas trees main parameters.
Material classes for body parts and gate valves shutoff elements correspond to API Spec 6A.
Working medium temperature to +121оС. Ambient temperature minus 60оС to +40оС. The equipment is manufactured to API Spec 6A. Temperatures ratings L (-46оC to +82оС) to V (+2оС to +121оС).
Table 1. Christmas tree bores in mm
| Christmas tree vertical bore |
For side outlets of Christmas tree |
For side outlets of tubing head |
Nominal pressures,
МPа |
| 50 |
50 |
50 |
21, 35,
70, 105 |
| 65 |
50, 65 |
50, 65 |
| 80 |
50, 65, 80 |
| 100 |
65, 80, 100 |
Table 2. Bores for connecting flanges of Christmas tree tubing head vs Christmas tree vertical bore in mm
| Tubing head upper flange |
Tubing head lower flange |
Christmas tree vertical bores |
Nominal pressures,
MPa |
| 180 |
280 |
50, 65, 80 |
21, 35,
70, 105 |
| 230 |
100 |
Table 3. Maximum axial loads for hanged tubing string vs bores of tubes
Tube bore,
mm |
60 |
73 |
89 |
102 |
114 |
Nominal pressure,
МPа (psi) |
14
(2000) |
21
(3000) |
35
(5000) |
70
(10000) |
105
(15000) |
14
(2000) |
21
(3000) |
35
(5000) |
70
(10000) |
105
(15000) |
14
(2000) |
21
(3000) |
35
(5000) |
70
(10000) |
105
(15000) |
14
(2000) |
21
(3000) |
35
(5000) |
70
(10000) |
105
(15000) |
14
(2000) |
21
(3000) |
35
(5000) |
70
(10000) |
105
(15000) |
Maximum axial load,
Q, t |
15 |
20 |
30 |
45 |
70 |
20 |
30 |
45 |
80 |
100 |
30 |
45 |
65 |
100 |
130 |
30 |
40 |
60 |
100 |
150 |
35 |
50 |
75 |
120 |
150 |
Christmas tree design options
Main design features and advantages
- Valves body parts are forged that provides high strength and reliability.
- Available any standardized program acc. to GOST 13846 of AF type with hanging tubing string in mandrel hanger and of AFK type with hanging tubing string in adapter flange.
- Tubing string may be hanged both in tubing head mandrel hanger having rubber ring or metal-to metal seals and adapter flange having thread 60, 73, 89, 102 ; В-60, В-73, В-89, В-102; НКМ-60, НКМ-73, НКМ-89, НКМ-102 GOST 633-80 or acc/ to API Spec 5B TBG 2 3/8'', 2 7/8'', 3 1/2'', 4''.
- Design of tubing hanger and tubing head permits to install plug with back pressure valve to ensure replacing Christmas tree and side outlet gate valves without well killing under pressure.
- Side outlets of Christmas tree and tubing head have intermediate flanges with thermometer pockets to install thermometers as well as valves to install pressure gauges.
- The assembly is supplied with all necessary spare parts as well as maintenance tools.
|
