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A wellhead has, instead of a conventional Christmas tree, a spool tree (34) in which a tubing hanger (54) is landed at a predetermined angular orientation. As the tubing string can be pulled without disturbing the tree, many advantages follow, including access to the production casing hanger (21) fo

A wellhead has, instead of a conventional Christmas tree, a spool tree (34) in which a tubing hanger (54) is landed at a predetermined angular orientation. As the tubing string can be pulled without disturbing the tree, many advantages follow, including access to the production casing hanger (21) for monitoring production casing annulus pressure, and the introduction of larger tools into the well hole without breaching the integrity of the well.

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[ We claim:] [1.] A wellhead assembly for supporting tubing within a well for selective use with a blowout preventer having a BOP bore comprising:a housing;a spool tree adapted for disposal below the blowout preventer and fixed and sealed to said housing, said spool tree having a wall with a central

[ We claim:] [1.] A wellhead assembly for supporting tubing within a well for selective use with a blowout preventer having a BOP bore comprising:a housing;a spool tree adapted for disposal below the blowout preventer and fixed and sealed to said housing, said spool tree having a wall with a central bore therethrough and a first lateral port connected to a valve, said central bore having an internal surface and adapted to form a common passageway with the BOP bore;a tubing hanger landed and sealed within said spool tree at a predetermined angular position at which a second lateral port in said tubing hanger is in alignment with said first lateral port in said spool tree, said tubing hanger supporting the tubing;at least one vertical bore in said tubing hanger being sealed above said second lateral port by a first closure member, and said internal surface of said central bore through said spool tree being sealed above said tubing hanger by a second closure member, said closure members being retrievable through the BOP bore;a workover port extending through said wall of said spool tree for selective fluid circulation with that portion of said common passageway below the BOP bore and above said tubing hanger; andan annulus port extending through said wall of said spool tree for selective fluid circulation with an annulus around the tubing, said workover and annulus ports being interconnected via a flow passageway having at least one valve. [9.] A method for controlling fluid flow in a well comprising:suspending tubing from a tubing hanger;supporting and sealing the tubing hanger within the bore of a production member for selective disposal below a blowout preventer having a BOP bore;forming a common flow passageway between the BOP bore and a portion of the production member bore above the seals around the tubing hanger;extending a tubular member into the BOP bore, attaching the tubular member to the tubing hanger, and closing the blowout preventer therearound;forming a flowpath through the tubing and the tubular member, forming an annular area between the tubular member and the production member in the common flow passageway and forming an annulus around the tubing below the tubing hanger;forming a production passageway from the flowpath, through a lateral port in the tubing hanger and through the wall of the production member;controlling flow through the production passageway by a production valve;forming an annulus passageway from the annulus and through the wall of the production member;controlling flow through the annulus passageway by an annulus valve;forming a workover passageway from the annular area and through the wall of the production member;controlling flow through the workover passageway;providing fluid communication between the workover passageway and the annulus passageway;forming a crossover fluid passageway between the production passageway and annulus passageway;controlling flow through the crossover fluid passageway; andcirculating fluid downhole using the flowpath, tubing annulus, annulus passageway, workover passageway, and annular area. The method of claim 9 further including flowing fluid downhole through the workover passageway, the crossover passageway, and the production passageway. A method for controlling fluid flow in a well comprising:suspending tubing from a tubing hanger;supporting and sealing the tubing hanger within the bore of a production member for selective disposal below a blowout preventer having a BOP bore;forming a common flow passageway between the BOP bore and a portion of the production member bore above the tubing hanger;extending a tubular member into the BOP bore, attaching and sealing the tubular member to the tubing hanger, and closing the blowout preventer therearound with the tubular member in fluid communication with said tubing flowbore;forming a flowbore through the tubing, an annulus around the tubing below the tubing hanger, and an annular area between the tubular member and production member in the common flow passageway;forming a production passageway from the flowbore, through a lateral port in the tubing hanger and through the wall of theproducfion member;controlling flow through the production passageway by a production valve;forming an annulus passageway from the annulus and through the wall of the production member;controlling flow through the annulus passageway by an annulus valve;forming a workover passageway communicating with the annular area through the wall of the production member;controlling flow through the workover passageway;providing fluid communication between the workover passageway and annulus passageway;forming a crossover fluid passageway between the production passageway and annulus passageway;controlling flow through the crossover fluid passageway;installing a tubing hanger closure member in the tubing hanger above the production passageway;removing the tubular member; andflowing fluid through the production passageway, through the crossover passageway and into the annulus passageway. A method for controlling fluid flow in a well comprising:suspending tubing from a tubing hanger;supporting and sealing the tubing hanger within the bore of a production member for selective disposal below a blowout preventer having a BOP bore;forming a common flow passageway between the BOP bore and a portion of the production member bore above the tubing hanger;forming a flowbore through the tubing and an annulus around the tubing below the tubing hanger;forming a production passageway from the flowbore, through a lateral port in the tubing hanger and through the wall of the production member;controlling flow through the production passageway by a production valve;forming an annulus passageway from the annulus and through the wall of the production member;controlling flow through the annulus passageway by an annulus valve;installing a tubing hanger closure member in the tubing hanger above the production passageway;installing an internal closure member within the portion of the production member bore above the tubing hanger;forming a workover passageway through the wall of the production member from the bore of the production member above the tubing hanger and between the tubing hanger closure member and internal closure member;controlling flow through the workover passageway;forming a crossover fluid passageway between the production passageway and annulus passageway;controlling flow through the crossover fluid passageway;providing fluid communication between the workover passageway and the crossover fluid passageway; andflowing fluid through the production passageway, through the crossover passageway and into the workover passageway between the tubing hanger closure member and the internal closure member. An assembly for producing a well comprising:a wellhead supporting a casing hanger that suspends casing which forms a casing annulus;a pressure monitoring valve disposed within said wellhead on said casing hanger and connected to a passageway extending to the casing annulus for monitoring the pressure in the casing annulus;a spool tree mandrel projecting into said wellhead and disposed on said pressure monitoring valve;a completion tree connected to said wellhead;a drilling blowout preventer connected to said completion tree;said wellhead, completion tree and blowout preventer forming a common bore;said completion tree having a master horizontal bore, an annulus horizontal bore, and a workover bore;a production master valve connected to said master horizontal bore;an annulus master valve connected to said annulus horizontal bore;a workover valve connected to said workover bore;a pressure monitoring port extending through said completion tree and spool tree mandrel and communicating with an annular space above said pressure monitoring valve;an orientation sleeve associated with said spool tree mandrel and having an orienting cam surface;a tubing hanger lowerable through said common bore and having a side master port and a side annulus port, said tubing hanger having an orienting cam member engaging said orienting cam surface to align said side master and annulus ports with said master and annulus horizontal bores in said completion tree;said tubing hanger suspending tubing within said casing and forming a tubing annulus;a tubing hanger plug disposed in said tubing hanger for plugging said tubing hanger above said side master port;an isolation member mounted at least partially within said completion tree above said tubing hanger and having a central bore;an isolation plug disposed within said isolation member for plugging said central bore;a cover disposed on said isolation member and covering said common bore; andsaid workover bore communicating with said common bore between said tubing hanger plug and said isolation plug. A spool tree assembly for use selectively with a blowout preventer for operating a subsea well, comprising:a spool body adapted for disposal below the blowout preventer and having a central bore therethrough, a portion of said central bore being formed by an internal generally vertical wall surface, said internal generally vertical wall surface having an opening therein;a tubing hanger assembly mounted and sealed in a predetermined angular position within said central bore of said spool body and suspending tubing within the well, said tubing hanger assembly and tubing forming a central passageway therethrough and an annulus around the tubing below the tubing hanger;said spool body and said tubing hanger assembly having a production passageway extending from said central passageway of said tubing hanger assembly into said wall of said spool body;said spool body and said tubing hanger assembly having an annulus passageway extending from said annulus around the tubing below the tubing hanger and into said wall of said spool body;said spool body having a workover passageway extending from said opening in said central bore and into said spool body wall, said opening in fluid communication with said central bore above the tubing hanger; andsaid annulus passageway and workover passageway being in fluid communication through a flowpath to selectively circulate downhole from said central bore of said spool body through said workover passageway and annulus passageway with flow through said tubing hanger assembly annulus and central passageway of said tubing hanger assembly. The spool tree assembly of claim 14 further comprising a closure member sealingly disposed within said central bore of said spool body to control flow through said central bore. A spool tree assembly for use selectively with a blowout preventer having a BOP bore for operating a subsea well, comprising:a spool body adapted for disposal below the blowout preventer and having a generally cylindrical wall forming a central bore therethrough, a portion of said central bore being adapted to form a flow passageway with the BOP bore;a tubing hanger assembly mounted and sealed within said central bore of said spool body and suspending tubing within the well said tubing hanger and tubing forming a central passageway in fluid communication with said central bore of said spool body above said tubing hanger assembly and forming an annulus around the tubing below the tubing hanger;said spool body and said tubing hanger assembly having a production passageway extending from said central passageway of said tubing hanger assembly into said wall of said spool body;said spool body and said tubing hanger assembly having an annulus passageway extending from said annulus around the tubing below the tubing hanger and into said wall of said spool body;said spool body having a workover passageway extending from said portion of said central bore of said spool body and into said spool body wall for fluid communication with said portion of said spool body central bore above said tubing hanger;said annulus passageway and workover passageway being in fluid communication through a flowpath outside of said central bore of said spool body;a first closure member mounted within said central passageway of said tubing hanger assembly to control flow through said central passageway and through said central bore of said spool body; anda second closure member sealed and locked internally of said portion of said central bore above said tubing hanger assembly. The spool tree assembly of claim 16 wherein said workover passageway is in fluid communication with said portion of said central bore between said first and second closure members. A wellhead for supporting tubing for use selectively with a blowout preventer having a BOP bore comprising:a wellhead housing;a spool tree adapted for disposal below the blowout preventer and fixed and sealed to said housing, said spool tree having a wall with a central bore therethrough and at least a first lateral production fluid outlet port connected to a valve, a portion of said central bore being adapted to form a common passageway with the BOP bore;a tubing hanger supporting the tubing and landed and sealed within said spool tree at a predetermined angular position at which a second lateral production fluid outlet port in said tubing hanger is in alignment with said first lateral production fluid outlet port in said spool tree;at least one vertical production fluid bore in said tubing hanger being sealed above said second lateral production fluid outlet port by a first removable closure member, and said portion of said central bore through said spool tree being internally sealed above said tubing hanger by a second closure member removable through the BOP bore;a workover port extending at least partially through said wall of said spool tree from an area in said portion of said central bore between said two closure members; anda tubing annulus fluid port extending at least partially through said wall of said spool tree from an annulus formed around the tubing; said workover and tubing annulus ports in said spool tree being interconnected via a passageway having at least one valve. A spool tree system for use selectively with a blowout preventer having a BOP bore for a subsea well, comprising:a spool tree having a bore therethrough, a portion of said bore being adapted to form a flow passageway with the BOP bore upon installing the blowout preventer above said spool tree;a tubing hanger suspending tubing and supported by said spool tree, seals sealing between said tubing hanger and said spool tree, said tubing hanger and tubing having an internal production bore extending downwardly into the well and forming a tubing annulus extending downwardly into the well;said spool tree and tubing hanger forming a lateral production flowpath in fluid communication with said internal production bore and having a production control valve for opening and closing said lateral production flowpath to control flow therethrough;said spool tree forming an annulus flowpath in fluid communication with said tubing annulus and having an annulus control valve controlling flow therethrough;said spool tree having a workover flowpath through the wall of the spool tree communicating with said portion of said spool tree bore above said seals and having a workover valve controlling flow therethrough;a circulation flowpath being formed through said internal production bore of said tubing hanger with said lateral production flowpath closed and through said tubing annulus to selectively circulate fluid downhole using said internal production bore and said tubing annulus; andsaid internal production bore above said lateral production flowpath being adapted for isolation from said spool tree bore portion.