We claim: 1. A hydraulic torque wrench system comprising: a hydraulic cylinder unit having a hydraulic cylinder within a body; a ratchet unit having a ratchet mechanism located within a housing; said housing being generally oval in shape having a partial peripheral wall and opposing planar sidewalls; said ratchet unit including at least one drive plate having an upper lever portion and a lower ratchet portion; said at least one drive plate lever portion having means for rotatable attachment with said hydraulic cylinder unit for reciprocal motion generally parallel with said housing planar sides; said ratchet housing having a male connector cylindrical boss portion extending outward rearward from an upper perimeter portion of said housing and in communication with the interior of said housing in the vicinity of said drive plate lever portion; said ratchet mechanism having a rotatable ratchet wheel having teeth located around its periphery and positioned for rotation within said at least one drive plate within said lower ratchet portion and mounted for rotation between opposing planar sides of said housing; said hydraulic cylinder unit defining a central, longitudinal axis and having a female connector cylindrical boss located at a forward end thereof, a perpendicular cylinder end wall having and axially located busing, and a rear free end portion having an end cap, said body defining an axially located cylinder having a reciprocating piston located therein for reciprocal movement there along between said end wall and said end cap, said piston having a piston rod mounted thereon and extending axially there from and extending forward through said bushing and into said female connector cylindrical boss and ending in an actuating end; said body having hydraulic connectors for introduction of prewired hydraulic fluid into said cylinder for driving said piston and piston rod, means for operatively connecting said piston rod actuating end and said upper lever portion for actuating reciprocal motion of said upper lever portion for driving said ratchet wheel; and means for operatively connecting said male connector cylindrical boss of said ratchet unit within said female connector cylindrical boss of said hydraulic unit at one of a plurality of selected circumferential positions; whereby said ratchet unit is operatively connected at a desired angle to said hydraulic unit to facilitate the use of the torque wrench system in a confined workspace and avoid twisting hydraulic feed lines to said hydraulic connector. 2. The hydraulic torque wrench system of claim 1, wherein said male connector cylindrical boss of said ratchet unit has a plurality of outward opening, racially directed, circumferentially spaced, bores, and said female connector cylindrical boss of said hydraulic unit has a plurality of racially directed, circumferentially spaced through-bores corresponding in location to said bores of said male connector cylindrical boss, and further comprising a plurality of pins, each removable insert able through a through-bore of said female connector cylindrical boss and into a corresponding outward racially opening of said male connector cylindrical boss of said ratchet unit, whereby said male boss is inserted into said female boss, turned to a desired angle, and said plurality of pins inserted within matching male boss outwardly opening bores and female through-bores. 3. The hydraulic torque wrench system of claim 2, wherein each said through-bore of said female connector cylindrical boss is a tapped thread, said outward opening bores of said male connector cylindrical boss are tapered inwardly, and each of said pins is a bolt having a threaded outer portion with an end located drive structure and an inwardly tapered inward portion and sized and configured to fit within an aligned pair of said tapered bore and to screw into said threaded through-bore by means of a driver until a snug fit is achieved. 4. The hydraulic torque wrench system of claim 1, wherein said ratchet wheel includes one of a male drive shaft for receiving a socket tool and a female box drive unit having a coaxial polygonal cylinder unit wall for driving a nut on a fastener. 5. The hydraulic torque wrench system of claim 1, wherein said means for operatively connecting said piston rod actuating end and said drive plate lever portion is a connecting rod having a crank receiving end having a crank bore there through and an actuated end mounted for rotatable transmitting force between said piston rod actuating end and said actuated end. 6. The hydraulic torque wrench system of claim 5, said connecting rod actuated end being a pin end having a fitted pin extending perpendicularly there through and having a spherical end for fitting to said piston rod actuating end, said actuating end having a spherical radius bore therein and a piston rod connector extending from said actuating end having opposing connectors extending from the periphery of said actuating end having “L”-shaped pin receiver slots for receiving opposing ends of said pin fixed within said con- necting rod spherical end, and wherein said pin end con- forms to said spherical radius bore of said piston rod actuating end for transmitting force there between within the rotation of said pin end of said connecting rod. 7. The hydraulic torque wrench system of claim 5, said connecting rod actuated end being a hub screw end having a perpendicular threaded receiving bore there through and having a spherical end for fitting to said piston rod actuating end, said actuating end having a spherical radius bore therein and piston rod opposing connectors extending from the periphery of said actuating end having a bore for rotatable receiving said hub screw, and wherein said threaded bore end conforms to said spherical radius bore for transmitting force there between within the rotation of said hub screw end of said connecting rod by means of said bore extending through said piston rod connectors. 8. The hydraulic torque wrench system of claim 5, wherein there are two driving plates mounted side-by side and having mutually inwardly stepped lever portions having aligned crank bores, and a crank pin of such dimensions as to lit within said aligned bores, said crank receiving end of said connecting rod being mountable on said crank pin between said stepped lever portions. 9. The hydraulic torque wrench system of claim 8, wherein said ratchet mechanism housing is integral and having an upper peripheral access area having a cover plate for covering the upper access area of said housing during use, and a lower peripheral opening for insertion and removal of said ratchet mechanism driving plates. 10. The hydraulic torque wrench system of claim 5, wherein there is one driving plate which has side surfaces, and said upper lever portion declines a slot parallel with said side surfaces of said driving plate and of such width and dimensions as to receive said crank receiving end of said connecting rod, said upper lever portion having a crank bore there through for receiving a crank pin of such dimensions as to rotatable fit within said crank receiving end, said slot allowing rotating movement of said connecting rod when activating said lever portions in a forward or rearward direction during operation of said torque wrench. 11. The hydraulic torque wrench system of claim 10, wherein said driving plate includes a first spring driven drive pawl having teeth corresponding to said teeth on the periphery of said ratchet wheel such as to rotatable drive said ratchet wheel in one direction by engaging said teeth as said driving plate is rotated by the extension of said connecting rod against said lever portion, said spring-driven drive pawl allowing said driving plate to ratchet to its original position without turning of said ratchet wheel in the reverse direction. 12. The hydraulic torque wrench system of claim 11, further comprising a second spring-driven pawl attached to an inner side of a lower peripheral wall of said housing at an upper end for rotation to said lower peripheral housing and having teeth corresponding to said ratchet wheel teeth such as to engage said ratchet wheel and prevent turning of said ratchet wheel in said reverse direction, said second driven pawl having at least one pin rotatable extending through a said housing sidewall having a lever mounted thereon exterior to said side wall, whereby, upon manipulation of said lever, said second driven pawl is engaged or disengaged with said ratchet wheel as desired to prevent or allow reverse turning of said ratchet wheel. 13. The hydraulic torque wrench system of claim 9, wherein said ratchet mechanism housing is split into opposing halves at the center of its periphery and said male connector cylindrical boss, one of said halves having peripherally located threaded bores and the other of said halves having bores corresponding to said threaded bores for receiving cap screws of such configuration as to fasten said halves together upon insertion and tightening of said cap screws into said threaded bores. 14. The hydraulic torque wrench system of claim 1, said hydraulic cylinder unit having a hydraulic lifting boss extending upward from said cylinder end wall, said fitting boss having a rectangular, planar, horizontally disposed Hat having a first bore and a spaced second bore, each being configured to receive corresponding said hydraulic connectors, said first bore being fluidly connected through said body to said cylinder at a point adjacent said end cap, said second bore being fluidly connected through said body to said cylinder at a point adjacent said end wall, whereby fluid introduced under pressure through said first bore drives said piston toward said end wall for driving said ratchet unit, and whereby fluid introduced under pressure through said second bore drives said piston to its original position. 15. The hydraulic torque wrench system of claim 14, each said hydraulic connector having a swivel fitting at said respective first and second bores. 16. The hydraulic torque wrench system of claim 1, said hydraulic cylinder unit having a hydraulic collar encircling said body at said cylinder end wall, said hydraulic collar having three axially spaced O-rings separating said hydraulic cylinder unit and said hydraulic collar forming first and second circumferential hydraulic fluid passages, said hydraulic collar having a mounting fitting there through for receiving a three-way pivot hydraulic fitting, said hydraulic fitting having a single vertical swivel fitting for attachment to said hydraulic: collar and an upper portion having iirst and second opposed mounting lettings for receiving hydraulic swivel fittings for attachment to first and second hydraulic supply hoses, said vertical swivel fitting having first and second hydraulic fluid bores providing fluid communication between said first and second opposed mounting fittings and said first and second circumferential hydraulic fluid passages, respectively, said first circumferential fluid pas- sage being fluidly connected through said body to said cylinder at a point adjacent said end cap, said second circumferential fluid passage being fluidly connected through said body to said cylinder at said end wall, whereby fluid introduced under pressure through said first opposed fitting drives said piston toward said end wall for driving said ratchet unit, and whereby fluid introduced under pres- sure through said second bore drives said piston to its original position. 17. The hydraulic torque wrench system of claim 1, further comprising a retainer cap, said end cap having means for removable mounting said retainer cap at said rear free end, said retainer cap extending over said free end and forward over hydraulic cylinder unit so as to cover a free end portion, and wherein the outer surface of said hydraulic cylinder unit is polygonal in shape between said hydraulic connectors and said retainer cap. 18. The hydraulic torque wrench system of claim 17, wherein said end cap defines an axial, rearward opening,  cylindrical recess forming a threaded end cap accessory receiver having an interior threaded surface and said means for removable mounting said retainer cap is a cylindrically shaped, axially located retainer cap threaded boss located or1 the interior of said retainer cap, said threaded boss being of such size and dimensions as to screw into interior threaded surface of retainer cap receiver. 19. The hydraulic torque wrench system of claim 18, further comprising a reaction bar having an attachment sleeve portion, an angled trunk portion, and a rectangular base portion having a base bearing wall, said attachment sleeve portion having a polygonal interior surface of such size and configuration as to sliding fit over and cover said polygonal body so as to turn therewith, whereby said reaction bar is mountable on said polygonal body by removing said retainer cap, sliding said attachment sleeve portion over said polygonal body at a selected position such that said base bearing wall bears against the perimeter of a flange when said ratchet unit is drivingly connected with a nut of a flange fastener for the torquing thereof, and reinstalling said retainer cap, said retainer cap serving as a reaction bar retainer, thereby holding said reaction bar in a desired position on said body. 20. The hydraulic torque wrench system of claim 18, further comprising a reaction boot having an upper attachment sleeve portion and a rectangular base portion, said attachment sleeve portion having a polygonal interior surface of such size and configuration as to sliding fit over and cover said polygonal body so as to turn therewith, said rectangular base portion having a bearing surface at an end thereof, whereby said reaction boot is mountable on said polygonal body by removing said retainer cap, sliding said attachment sleeve portion over said polygonal body at a selected position such that said rectangular base bearing surface bears against a nut of an adjacent flange fastener upon the torquing of a nut by said hydraulic torque ratchet, and reinstalling said retainer cap, said retainer cap serving as a reaction boot retainer, thereby holding said reaction boot in a desired position on said body. 21. A hydraulic torque wrench having a ratchet mechanism having a housing operatively connected with a hydraulic drive cylinder piston and piston rod by means of a connecting rod and having a generally cylindrical body, the improvement comprising: said ratchet mechanism housing and said hydraulic drive cylinder cylindrical body having means for mutual detachment and reattachment at a selected one of a plurality of relative angles such that said ratchet mechanism may be installed at a selected angle relative to a fixed said cylindrical body; whereby said cylindrical body is be held in a fixed position relative to attached hydraulic fluid lines while operating said ratchet mechanism at a selected angle convenient for torquing nuts or heads of fasteners on-a particular piece of equipment such as a pair of joined pipe flanges. 22. The improved hydraulic torque wrench of claim 21, wherein said means for mutual detachment and reattachment comprise: a male cylindrical boss connected to said housing of said ratchet mechanism and communicating with the interior of said housing such that said connecting rod is reciprocally movable there through when driven by said hydraulic drive piston rod; a female cylindrical boss connected to and extending axially from said cylindrical body at an end wall thereof, and means for securing said male cylindrical boss within said female cylindrical boss at a selected rotational angle of a plurality of angles therewith; whereby said hydraulic drive piston rod is reciprocally extendable axially through said end well. 23. The improved hydraulic torque wrench of claim 22, wherein said male cylindrical boss of said ratchet unit has a plurality of outward opening, racially directed, circumferentially spaced, bores, and said female cylindrical boss of said cylindrical body has a plurality of racially directed, circumferentially spaced through-bores corresponding in location to said bores of said male cylindrical bores, said means for securing said male cylindrical boss within said female cylindrical boss at a selected rotational angle comprising a plurality of pins, each removable insert able through a through-bore of said female cylindrical boss and into a corresponding outward racially opening of said male cylindrical boss of said ratchet unit, whereby said male boss is inserted into said female boss, turned to a desired angle, and said plurality of pins inserted within matching male boss outwardly opening bores and female through-bores. 24. The improved hydraulic torque wrench of claim 23, wherein each said through-bore of said female cylindrical boss is a tapped thread, said outward opening bores of said male cylindrical boss are tapered inwardly, and each of said pins has a threaded outer portion with an end located drive structure and an inwardly tapered inward portion and sized and conjured to fit within an aligned pair of said tapered bore and to screw into said threaded through-bore by means of a driver until a snug lit is achieved.   液压扭矩扳手系统技术英文文献和翻译(2):http://www.youerw.com/fanyi/lunwen_11552.html