In recent years with the development of two-stage multi-stage casing cementing Cementing head technology has been widely used. Since 1992, Texas has been committed to high-tech Co. continental shelf oil and gas development and research work Cementing head, and the successful development of the DDS series Cementing head, the series Cementing head suitable for Φ139.7mm, Φ177.8mm, Φ244.5mm, Φ339 .7mm casing cementing operation, simple structure, convenient and practical application. In the major oil well cementing operations have been widely used.
1, Cementing head structural features
1. The barrel is the main Cementing head, used to place the stopper and controlled release stopper. Welded indicator above it, stop pin seat, balanced three Φ50.8mm fittings and Hammer Uniom fittings, following two Hammer Uniom connectors are used to connect pipelines for pulp and cementing, the above Hammer Uniom joint to control stopper release. When the confirmation rubber plug into the sleeve, can be removed above the connecting line, install a pressure gauge to monitor the cementing process. Circulating mud, cementing, replacement and other cementing operations, can be conveniently accomplished using Cementing head.
2. Unique quick oil azelaic male connector structure consists of quick, quick female connector Hammer Uniom nut 3 parts. Quick connect male connector with sleeve, quick connection with cylindrical female connector, the male and female connector Hammer Uniom nut by caulking, docking at the male and female connectors increased by a O-ring to ensure the safe and reliable use. Cementing head orientation can be easily adjusted by the structure, it is possible to adjust the direction of Cementing head based on the position and drilling pump cement truck when the field application, so that the connecting manifold more flexible.
3. opened a symmetrical four notches on the top cover, it can be used a crowbar to open or tighten.
4. Replace the rubber plug at both ends of the cylinder design has a balance pipe segment to communicate in case cementing operations, resulting slurry rapidly drops local vacuum stopper at one end, so that enormous pressure stopper formed at both ends poor, resulting in damage to the stop pin. Compared with the old Cementing head, its design takes into account additional safety factors, thus extending the life of Cementing head.
5. Design has leveraged indicator, the wedge block with instructions to dial 90 ° to the handle by a shaft connected to the cylinder body is rotated so the wedge block can dial into the outer cylinder rotating handle instruction indicating whether to enter through Cementing head stopper casing, to facilitate the construction site.
6. top and quick Hammer Uniom at both large trapezoidal thread pitch, ensuring easy operation and quick.
7. The overall design with a modular structure, from the cylinder, spiral retaining pin assembly, quick by independent parts azelaic joint assembly and other components, such as a part of the damage can be individually replaced, with good mutual change, reducing the cost.
2, Cementing head main technical parameters
The main technical parameters DDS series Cementing head of Table 1

3, Cementing head the working process and principle
The following two-stage cementing operation as an example. Working process and the principle of DDS series Cementing head.
(1) mounted on the wellhead Cementing head, took over the sink, the following two Hammer Uniom joints were connected to the pump and drilling cement truck, the top stopper contact pressure manifold. Note that the stop pin screwed into the screw, wedge block extend dial.
(2) remove the cap, into a rubber plug. Open drilling pump cycle, injection isolated liquid cementing.
(3) Open spiral stop pin, pressure stopper. Carefully observe the pointer moves stopper has been confirmed by ledges, open drilling pump replacement, until the level of bumping, back pressure, see anti-backpressure is reliable.
(4) back pressure, reliable, unloading roof, cast shells plug, re cycle spiral ledges, the wedge block dial appropriated extended position, mounted close plug, replace the top cover until the shells sit in a predetermined position, the open Open two-stage pump pressure - hoop, circulating mud.
(5) After a period of WOC, re-circulating mud, spacer fluid injection, for secondary cementing. Note finished cement, open the stop pin, pressure stopper until stopper by stopper pin, pump replacement. After bumping, back pressure, see close is good.
4, Cementing head application and effect
Since DDS series Cementing head from the successful development, it has been applied in QK-4 well Jiangsu Oilfield, Huabei Oilfield text 23-2 #, Tabei of sand 42 wells in oil and gas well cementing operations. Cementing head of the operation, use and pressure and other indicators
We have reached the design requirements. Yanchang Oilfield in 1994 ordered a DDS5 type cementing Cementing head has accumulated over a hundred times, just change a few deputy seals. DDS series proved Cementing head operation simple to use, safe and reliable performance, easy maintenance, has good prospects.
TaiXing Shiji Dongfang Machinery Manufacturing Co.,Ltd. production of patented products: integral cementing head, has become today's most popular Cementing head.