With the development of oil production, the oil reservoir fracturing become long-term yield, high-yield primary technical measures. In recent years, fracturing technology has developed rapidly, the urgent need to meet the high pressure, large displacement, high sand ratio, large sand diameter, large amount of sand and high viscosity fracturing fluid and other working conditions of complete sets of fracturing equipment.
In order to meet the above needs, we have since 1973 carried out a 70 kg / cm Fracturing manifold experimental study, and in March 1975 in my office the first trial drilling machinery repair sleeve sinks. This sleeve exchange, at 1000 kg / cm hydrostatic test and 70 kg / cm dynamic pressure test after passing into field trials in May, has in Jiannan Gas Field Oilfield acidizing and fracturing seven wells, the maximum pump pressure 605 kg / cm, the maximum displacement of 1925 l / min.
First, the structural description
700 kg / cm Fracturing manifold (Figure 1) is mainly composed Check valve 2, Plug valve 4, Vent valve 5 and Hammer Union, Tee, Cross Tee, Pup joint and other components. A total of 81 connectors, which are equipped with Check valve 41 connectors can be connected to 41 sets of Fracturing Truck, Vent valve equipped with two connectors accept venting Line, the other two joints and fracturing wellhead connection.

Figure 1 700 kg / cm Fracturing manifold
1-2 "Hammer Union; 2- Check valve; 3-2 1/2" Hammer Union; 4- Plug valve; 5- Vent valve; 6-3 "Hammer Union
Line two main manifold middle of center distance of 780 mm, can be fixed on or CA- 01 girders CA-03 liberation of the car, constitute Manifold truck. Main Line diameter of 54 mm, Supported Line diameter is 46 mm. Support Line ends equipped with 2 "Hammer Union, can be directly connected with the SYC-700 and YLC-500 Fracturing Truck.
This manifold Check valve used in Figure 2, which is characterized by simple manufacture, easy maintenance. It's Valve assembly with ACF a 7 00 Fracturing Valve assembly structure similar Truck, reliable, less prone to sand trapping, and longer service life.

Figure 2 Check valve
1- gland; 2 - spring; 3- Valve assembly; 4- Valve cup; 5- body
Plug valve structure shown in Figure 3, between the tap and the valve body has a pair of valve, the valve clearance can be adjusted, cocks, between the three through gland body 5, so that both the seal, and the switch than lightweight. Valve chamber shall be filled with high-pressure grease seal to improve sealing and lubricating properties.

Figure 3 Plug valve
1- runner; 2 - cock; 3 - the body; 4- valve; 5- Gland
This Plug valve disassembly convenient, fast switching (turn 90 ° open, reversed 90 ° off), compared with the same type of cone Plug valve (cock a conical surface) and valve switching torque is small, it is suitable for Fracturing manifold of total gate.
Vent valve (Figure 4) structure is simple, reliable, easy processing and switching effort under high pressure, particularly suitable for use as pressure relief valves.

Figure 4 Vent valve
1- gland; 2 - the body; 3- Valve; 4- Valve cup; 5- pressure cap; 6- stem
Second, the test case
1, hydrostatic test
Manifold in Check valve, Plug valve, Vent valve and activities had elbow were hydrostatic test individual components, sealing test pressure of 800 kg / cm, strength test pressure of 1000 kg / cm. After passing the test individual components, assembled according to Figure 1 and the overall test, the test pressure of 1000 kg / cm within 10 minutes no seepage does not leak, did not drop.
2, the dynamic pressure test
Mounted on the manifold Check valve connectors are connected to five SYC a 700 Fracturing Truck, joints of a blocked main Line, a nozzle mounted on the remaining connectors blocked. Be 700 kg / cm hydrodynamic test within 30 minutes no seepage does not leak.
3, field test
This manifold has been carried out in Jiannan Gas Field acidizing a well, and later in Oilfield were six wells fracturing, construction parameters as follows.
700 kg / cm acidification fracturing Fracturing manifold datasheets

Fracturing manifold of the main components are the three valves. Check valve wells after fracturing 4, after examination Valve rubber is still very good. Due to Fracturing Truck Line no relief valve discharge, so when Fracturing Truck parking fracturing process whether seal trials can not see it. But our analysis, as long as the Valve Check valve rubber is not bad, Fracturing Truck in the middle of the park construction, the Fracturing Truck Line relief valve outlet opening, so that both sides Check valve caused by the pressure difference, it should be sealed. Plug valve also conducted a field test four wells. Two Plug valve quality first working well enough (cocks, valves and valve body through hole misalignment), so by sand erosion wear more serious, but still can be sealed. In September we trial of the four Plug valve, are done once assembled, a pressure test. Prepare sink mounted on the second sleeve field trials. Vent valve after acid fracturing test seven wells, sealing reliable, flexible and light switch.
Third, a comprehensive opinion
(A) This Fracturing manifold can basically meet the current acidification fracturing, fracturing acidification at 700 kg / cm pressure. It recommended small batch production, to expand the test.
(B) Under the previous phase manufacture and test cases designed to make the following improvements:
1, Main Line and Tee, Cross Tee with 2 1/2 "threaded hose connection, processing requirements, the use of 700 kg / cm lower (especially after acidified) Seal unreliable and Tee and Cross Tee's installation location is not easy to adjust, not installed. switch T 58 × 5-3 and T70 × 4-3 trapezoidal buckle connection with O-ring seal. Adjust the mounting position of Tee and Cross Tee can be achieved by shims flange connection. Plug valve also switch (T58 × 5-3) trapezoidal threaded connection.
2. Connect Line with 3 "drill, the longest 4 meters, weighing more than 100 kilograms, the weight is too large, easy to install. Great Events elbow weight (over 60 kg) easily installed from the manifold outlet to the wellhead. Change with 2 "drill, lengths of 3 m, 2 m and 1 m, and the activities of elbow amended accordingly, reduce weight, easy to install.
3, according to the new process requirements, the Plug valve consists of two to five, and the addition of two needle valves (adaptation pitching and telemetry requirements). Modified structure shown in FIG. 5.

5 700 kg / cm Fracturing manifold improvement program (not shown on the left part of the same Fig. 1)
1- Check valve; 2- Plug valve; 3- Vent valve; 4- Needle valve