Description
The coupling make-up machine, also called as coupling application
machine, is a dedicated equipment that is used to screw or unscrew
couplings on casing/tubing in production of oil casing/ oil tubing.
It possesses following features: 1. Torque essentially depends upon
tube size meeting requirements for various kinds of connecting
threads. 2. Appropriate length of tongs teeth, hence minimizing
damage to coupling. 3. Variation of r.p.m is controlled by
microcomputer so as to meet requirements of special threads for
very low rotation (0.***1 r.p.m.). 4. Back tong is floating, thus
preventing influence on screwing from slight bend of tube. 5.
Clamping of back tong is realized by direct clamping method,
instead of previous rotation clamping, further lightening teeth
marking on tubes. 6. High reliability, resulting from improvements
based on experience of more than **0 sets of the machines. Main
technical parameters are briefed as below: Diameter of applicable
tubes: diameter*8.*6mm***7.8mm (1.9"*7"). Torque: Max. *0 KN.m
(****0 lbf.ft); *5 KN.m (****0 lbf.ft) at higher speed gear
Revolution speed: 0.***2 rpm at lower speed gear; 0.***2 rpm at
higher speed gear Rated flow rate of hydraulic pump: *****5 l/min
(***0 GPM) Rated pressure for hydraulic system: *1 MPa (***0 psi)
Pressure for pneumatic system: 0.**0.6 MPa A. Revolution Speed
Double-pump air-cooled power unit is adopted with stepless-variable
drive. Revolution speed of tong head is designed on two speed
gears. B. Torque 1. Maximum torque at low speed gear is different
from that at high speed gear. 2. Torque of back tong can be read
off torque meter, furthermore the connections of transmitter and
turns are provided. 3. Display and record on microcomputer. Torques
and turns can be read off microcomputer 4. Capacity: *0 pieces of
tubes per hour can be finished under the circumstances of rest
thread turns **5 after coupling is pre-screwed. 5. Operation
method: Manual operation. 6. Teeth markings: Teeth markings are
less than that stipulated in API if the screwing torque is in
conformity to API. C. Constitution A complete set of machine is
composed of main machine, power unit and operating console. The
main machine includes main tong and back tong. Main Tong 1. Close
type tong head is utilized. A coupling is clamped by the main tong
without traveling with threads. 2. Main tong is hydraulically
driven, being able to forward rotation or reverse rotation, and
gear drive is designed at two gears. 3. Clamping method: The
clamping is realized through rollers uphill of three jaw plates.
Three tong teeth for each jaw plate totaling 9 tong teeth are
equally arranged around **0 degree circumference of a coupling. The
variation of clamping force is directly proportional to the
variation of the torque of tong head. The higher the torque is, the
deeper the teeth markings are. Vice versus. The design of clamping
method results in minimum damage to coupling while necessary torque
4. The main tong is fixed with a connection used for counting
numbers of rotation, being able to output a signal every 3 degree
for instantaneous acquisition of turns and rotation speed (r.p.m).
Back Tong 1. The close type tong head is utilized. A tube is
clamped by the tong head, the back tong traveling with threads. 2.
The clamping method of the back tong is the same as the main tong.
The initial clamping force of the back tong is exerted upon by a
pneumatic cylinder. 3. The back tong is installed with a torque
transmitter to correctly measure torque values while screwing or
unscrewing. 4. The traveling of the back tong is driven by a
pneumatic cylinder with a trip to max. 0.8m. D. Control System 1.
The forward rotation or reverse rotation of the main tong is
controlled by a motor-driven hydraulic change-over valve. 2. The
pneumatic cylinder of initial clamping force of the back tong is
controlled by a motor -driven pneumatic valve. 3. The pneumatic
cylinder for traveling of the back tong is controlled by a
motor-driven pneumatic valve. 4. The flow rate is regulated with
the hand wheels of two hydraulic pumps of the power unit. 5. The
system pressure is regulated by pressure regulation of the power
unit. 6. The machine is equipped with a computer, being able to
display, record and print values of torques and turns, as well as
their variation curves. 7. Catching hold can be controlled through
torque (minimum, optimum, maximum), or turn (minimum, optimum,
maximum) respectively, or combination of the both, and displayed
& recorded as well.
