8 1/2" 635 Oil And Gas Tricone Drill Bit 216mm Dia Abrasion Proof

Drilling pressure is a necessary condition for bottom hole rock breaking. The size of the weight-on-bit determines the method and characteristics of rock breaking, which directly affects the drilling speed and the method of bit damage. During drilling, the drill bit is subjected to axial pressure and reversing force. The cutting teeth are worn, dull or damaged during the process of pressing and shearing the rock, which will inevitably affect the drilling speed. With the addition of weight-on-bit, the drilling speed will continue to improve, and the drill bit bearing and cutting teeth and other components will speed up wear and tear, affecting the penetration rate. The relationship between weight-on-bit and penetration rate has changed for three different periods.

During the appearance of crushing: when the weight on bit is less than the hardness of the rock, the cutting tooth can not cut into the rock, but can only crush the rock by friction method and wear on the cutting tooth greatly, though the drilling rate is also proportional to the increase of the bit-pressure Add, fatigue crushing period: When the weight on the drill press close to the rock into the hardness, although not cutting into the rock cutters, but in the rock face attack more cracks, the cutting teeth through the repetitive effect, but also the onset of volume crushing;

During the volume crushing, when the weight on bit is added to more than the rock press-in hardness, the cutting teeth cut into the volume of rock fragmentation, the drilling effect was significant before it is normal drilling. Therefore, it is necessary to be satisfied with the weight-on-bit applied to the roller cone bit that the cutting tooth can press into the rock and cause the volume of the rock to crumble.

After doubled the weight-on-bit test, the experimental roller cone bit was drilled to different grades of rock. The results showed that different rock types did not have the same penetration rate for increasing the weight-on-bit. In the meantime, the rate of drilling in medium-hard rock formations (rock grades 6-7) was relatively high, whereas relatively soft (rock grades 4-5) and hard (rock grades 8-9) . Drilling into the soft rock, easy to attack the water paste, drill bit pressure should be selected smaller. Drilling into the more abrasive formations, the lack of bit-pressure drill bit easy to form early wear-bit weight to be properly increased. Drilling fractured rock formation, prone to jumping, drilling pressure should be properly reduced to prevent collapse, cut cut teeth. The weight-on-bit is an important parameter for drilling. That is to say, it is necessary to give full play to the ability of the cutting teeth to cut into the rock formation and to reduce the wear of the cutting teeth maximally.

Description

CUTTING STRUCURES
1.Tailored insert shapes and grades manufactured using state-of-the-art tungsten carbide technology for different formations having varied drillability and compressive strength,to provide an optimum match beteen inserts wear resistance and toughness.
2.By using computer simulation of the rock bteaking at the bottom of the hole,Shareat’s engineers are able to design the best inserts space to ensure the most balanced load on each insert.
		3.Double rows of gage inserts For better maintaining full gage hole.
ROLLER BEARING
Based on the calculating of the load distribution on the bearing components,all shareate bits incorporate bearings that have optimal geometry and load distribution designed to give maximum bearing life.
1.Non-Sealed Bearings Bearing Type:Roller-Ball-Roller-Thrust Button without seal.
2.Sealed Bearings Bearing Type:O-Ring Seal-Roller-Ball-Roller-Thrust Button. See ·The seal keeps the mud,cuttings,air and water ouside the bearings. ·The bearing works in lubricant and friction conditions,this results in less bearing wear and longer bearing life.
LUGAND SHIRTTAIL ENHANCEMENT
	1.Conventional Shirttail DesignThis shirttail features a”terraced”design,which increases escape area and the bailing velocity and decreases cuttings regrind and wear on shirttail and shirttail lip. Hardmetal and wear resistant carbide were applied to shirttail and shirttail lip.
2.Particular Shirttail Design This shirttail features a”terraced”design,which increases eacape area and the bailing velocity and decreases cuttings regrind and wear on shirttail and shirttail lop. Hardmetal was applied to shirttail lip and lug.Wear resistant catbide on shirttail lip and lug and around the”terrace”lower part of shirttail lug.

  Hunan new diamond Construction Machinery Co., Ltd. is a professional engaged in the research and manufacture of drilling and pneumatic tools of modern high-tech enterprises。
   The main research and manufacture of high air pressure DTH hammer, drill hole, drill pipe and drilling tools, products are widely used in engineering, mining, engineering and construction engineering, water wells, geothermal drilling municipal engineering.

   The company which covers an area of 55,000㎡,currently employs more than 300 people, including 75 senior management technicians, both with rich professional skills and management capabilities.

      The"new diamond "quality and technical level of the leading domestic and international advanced level, has become the domestic and foreign well-known brands, praised by the majority of users, products are exported to Australia, Chile, Canada, South Africa, Ethiopia, Malaysia, South Korea, Brazil, Russia, Taiwan, Hongkong.