Block a canal up
During CFG picket becomes stake, tong block is in charge of at conveying pipeline or drill pipe core wait for place, tong cannot the edge carries passageway movement, call a canal. Blocking a canal up is to grow picket of CFG of the pump pressure inside helix bore canal to mix the problem that often encounters in material craft into picket, almost each building site has this kind of problem happening. It affects engineering construction plan directly, cause material to waste, increase the labor strength of construction personnel. If trouble removal is not complete, make already the CFG picket compound of agitate dehydrates or callous, return the possibility that can raise to block a canal up again, bring greater difficulty to construction. If processing is undeserved, still can cause picket, cause project quality accident. The analysis blocks tubal reason up, have the real sense of heavy Bi to making precautionary measures. According to spot experience, tong blocks common cause of the canal up to basically have the following sides:
1 Tong pump sends quantity and carry get speed to be not coordinated
Should carry auger speed is far when be less than Tong pump to send a volume, cause broach valve to export obstruction to increase, pressure is carried to increase with the Tong on duct road inside drill pipe at this moment, below the action that sends pressure in pump, separation of water of Tong incidental secrete. the arenaceous, clastic rock after breaking an oar to dehydrating, conduit or juncture of canal of drill pipe core, tortuous path and coarse face can make its transmission suffocate suffocate, very fast extruding is close-grained, cause a valve. Because carry,overcome get speed and Tong pump to send a quantity not to coordinate the measure that match and creates a canal, it is idea makes carry get speed and Tong pump to send a quantity to achieve dynamic balance, face of makings of the Tong in realizing broach to be the same as picket aperture namely is balanced relative to positional trends (graph 2) , that is to say expensive to M rice picket system, the Tong of the bulk such as its needs pump to send time to should be equal to drill pipe to promote M rice to need promote time to combine construction mechanism, reach not hard below formulary:
Carry in this craft get speed and pump to send a volume general all adjustable. Above all demarcate a variable, next according to type (1) or type (2) , through simple mathematical operation, can get coordinate another variable that match to it, realized the dynamic control to afore-mentioned balances thereby.
Should master next carry get an opportunity, stop to be gotten into after broach books elevation into be buried layer, begin pump to send Tong, after waiting for duct and canal of drill pipe core to be full of Tong, should carry in time auger, send pressure action to fall to handle bit easily grout fluid to squeeze in pump otherwise, can make broach a powerful person is in generation to do system of rigid Tong a place of strategic importance likewise, make pipeline bets a place of strategic importance.
Place of 2 conduit interface is sealed and lax oar of slack, leakage
What Tong leans in the transportation in conduit is pump sends pressure, and pump sends pressure to rely on among them fluid photograph material to deliver. If conduit juncture place is sealed and lax,meet slack or leakage oar, make Tong dehydrates thereby, break an oar and make carry obstruction to increase, cause a valve. Mix before construction so want in construction process at any time the sealed circumstance of joint of check conduit, discover the problem is solved in time.
3 broach valve is designed unreasonable or type choice is undeserved
The bit that some manufacturer produce its valve is sealed and lax, cut what liquefaction forms to exceed hole water pressure when the spiral ribbon that is versed in in the Ta in saturated sandy soil or powdery earth layer, can make mud arenaceous through valve osculatory aperture enters broach, form the arenaceous a place of strategic importance of certain ply, make Tong cannot fall normally, cause a valve. The length of some broach valve and design of open horn Mo are unreasonable, imperial mandate cannot open normal position into valve, also be one of matters that grand becomes all valves.
Return some broach valve not agile, frictional resistance power is too great, because pressure is little,Tong pump enters drill pipe hind and cannot open, cause a valve. The sealing of broach valve, flexibility and valve length should be checked when buying broach so, the rationality of opening angle.
At present picket of CFG of the pump pressure inside canal of long helix bore mixes material craft place to use bit into picket, by its the setting of valve and open direction cent are two kinds, one kind opens the door for side, another kind opens the door for the bottom. Former two parabola valve is designed in broach both sides, in be gotten into the process two valve are shut, prevent mud arenaceous enter drill pipe inside, cause drill pipe to jam. When pump sends Tong to reach broach floor two valve are opened, enter Tong fill hole from this inside. Latter is broach valve and get a needle to be one whole, when be being entered to run the drilling tool into the well sealed, carry the valve when getting to be down open below Tong extruding. Open the door with side broach photograph is compared, the characteristic that broach opens the door by is valve in broach bottom, the cannot open corrupt practice that prevents broach of side direction extruding to make. It is saturated pink when construction layer + or arenaceous + when, if use bit of side direction valve, right now the side outside valve besides bear outside side direction pressure of earth, bear even the lateral pressure that exceeds hole water, when the concrete lateral pressure of valve inside is less than the lateral pressure outside valve, can bring about valve cannot be opened and block a canal up, the bottom should be chosen to open the door when encountering layer of this cultivate land broach.
4 bend exhaust valve cannot normal open
Available air is filled inside the canal in the process sending with pump before Tong pump sends. To make air eduction, in oriented bend and the joint that lumen is in charge of place installs exhaust valve, carry the air inside the canal in the process with eduction Tong. When exhaust valve damages or be jammed by Tong, cannot work normally because of its and cause a valve.
5 carry pump job parameter to adjust undeserved
Carry pump to be with the Tong of D30 model exemple, general pump pressure is adjustable to 16MPa, tong exports pump to send pressure to be able to amount to 4MPa, if carry pressure of system of pump hydraulic pressure,tone is set too low, can cause a valve, additional, part of reversal valve part wears away component of discharge pressing, hydraulic pressure malfunctions, pressure short of asks, cross a serious offence small metropolis causes a valve.
6 Tong raw material and Tong cooperate to compare a choice undeserved
Choice of 1) Tong raw material is undeserved
The experiment makes clear, diameter of thick aggregate bead blocks a canal up easily greatly too, but bead way is too small, tong intensity is inferior. Combine construction experience, when thick aggregate uses pebble in proposal compound, the biggest diameter is 25mm, when using clastic rock, the biggest diameter is 20mm.
Cement should have the good performance that defend water, in making Tong sends a process in pump water of not easy secrete. Is grade of intensity of CFG picket Tong C15 commonly? C25, common silicate cement or scoria cement can satisfy a requirement. Grade of its cement intensity chooses P commonly. 032. 5, if use Zuo grade cement to make up, can make cement dosage slants little, affect its workability and packing, block a canal up easily.
2) Tong cooperates to compare a choice undeserved
After choosing Tong raw material correctly, of Tong cooperate to compare appropriate appeared crucial, because Tong cooperates,often use undeserved cause a valve. Basically be cement dosage little, arenaceous rate impropriety. The cause that creates this kind of appearance basically is a lab those who give out cooperate scale unreasonable, or raw material is metric forbid to do not have according to cooperate correctly to compare make up Tong. So according to cooperate suitably to compare making up Tong is one of important segment that make sure Tong is carried smoothly.
Control of 3) Tong slump is undeserved
In CFG picket construction Tong landslide is spent small or too cosmopolitan cause Tong pump to send difficulty and block a canal up. The transportation of concrete obstruction is reduced along with slump and increase, slump is too so small, make possibly of compound but pump sex is reduced apparently, namely not easy pump sends. But not be slump jumps over easy pump to send greatly more, because landslide spends congress to cause water of compound happening secrete or separation, inside Tong duct water on the surface arrives above, below pump pressure action, water flows first, aggregate and mortar are detached, thick aggregate is in the condition of mutual contact, friction is increased, cause a valve thereby. According to project practice, is the slump appropriate control of Tong of picket of CFG of the pump pressure inside canal of long helix bore in 160? 200mm.
Change aperture
In saturated pink earth and pink the construction in thin arenaceous layer encounters this kind of situation constantly. Be over when construction after a picket, in the process that in the vicinity of uses dozen of another root stake, as drilling tool get into, discovery already pile picket sinks very suddenly, Hu falls below the top several centimeters, amount to 2m above even. After Tong of new pile perfusion becomes stake, already pile sinks picket top picks up somewhat, also can pick up to carry elevation on the head to original stake sometimes, between this kind of two picket connect the phenomenon calls change hole. It is undeserved and easy to if to change Kong Fa shows to be mixed not in time,take step cause picket to carry elevation on the head under design elevation, picket body places the quality issue such as mud. Discover through observation already pile picket top sinks majority happening is carried in new pile in getting a course, because new pile is being gotten into downward,this may be when, cut vibration the energy in saturant pink earth and sandy soil layer is accumulated, make earthy layer liquefacient, after that pile is carried in getting a course, as a result of promoted attraction, bring about brief vacuum status appears inside aperture, when hour of the some in bore is vacuum, be equivalent to the head difference with tall 10m, make between two picket liquefacient earth layer flows to new pile direction, formed change hole so. The main method that solves change aperture is: Adopt the design plan that large stake spurs, avoid new pile to be opposite already of pile cut disturb; Adjust pile order, adopt lie between picket or lie between a platoon to jump dozen of method, jump dozen of ordinal span that inspect picket decide with earthy layer circumstance; Improve bit, raise drilling rate, decrease get earth of pair of saturated sandy soil, pink to cut disturb to be accumulated with energy, posture of liquefaction of abate land system. Should clear in time to the field of easy change aperture in construction process get into abandon land, the periphery in so that seasonable observation arrives,making new stake process already pile picket top sinks circumstance, carry when new pile get pump to send Tong to when producing layer of change aperture earth, should stop to carry auger, successive pump sends Tong to regain primary level till top of stake of change aperture stake.
Empty core of picket body upside or clip are arenaceous
Compound of picket of CFG of the pump pressure inside canal of long helix bore is protecting picket sometimes into picket craft or picket body air produces under protective picket core or clip are arenaceous, a few shallow centimeters, 1 deep meter many. There is partial stake to appear in construction of building site of business Qiu Mou for example this kind of phenomenon. The main reason that causes picket body empty core may be exhaust valve jams cannot will be in charge of normally inside air eduction, bring about Hu body to live energy of life, form empty core, to avoid picket body empty core, answer in construction often the working status of check exhaust valve, discovery jams clean in time.
Causing center of upside picket body to place arenaceous main reason may be carry when picket upside pump sends auger rate is too rapid, broach was not buried in Tong, the Tong of eduction of two side valve lapped collapse in Kong Li stream arenaceous; Another kind of circumstance is pump sends the layer in the process to the Tong of valve eduction laps float oar and be become however without cave in.
Hold back getting
Hold back is gotten even if point to long helix to be gotten in the drill pipe in be being gotten into the process to be down drilling rate too fast, outside causing the earth on spiral ribbon to have not enough time to take an aperture, and extruding is between drill pipe and hole wall, cause drill pipe to balk rotate, serious when the electric machinery of meeting attaint head. If appear,hold back is gotten, answer to put out circumgyrate power power supply instantly, after mentioning drill pipe with lowermost hoist speed, apply afresh auger can. Get the happening of the accident to prevent hold back, construction personnel should be organized before construction, feature of base area layer makes reasonable the programme of construction. Get into the process in construction in, the change that according to head working electric current is worth rotates to drill pipe speed and drilling rate undertake reasonable adjust, often use intermittent type to be gotten into the method commonly, get spurt to be gotten into for nothing namely, is the sky after getting design deepness gotten 30? 60s, after waiting for electric current to stabilize, stop auger.
Borer fixed position forbids
Picket cloth is set is axes of basis spot fixed position, each picket that gets on design blueprint the bamboo autograph fixed position that uses certain length is in on the spot. Land is abandoned when because grow helix bore,picket of CFG of the pump pressure inside the canal mixes material construction into picket more (graph 3)w, if abandon land cannot seasonable Qing Dynasty carries, as the addition that abandons land, find in construction already decided picket the mark is more difficult. The way that settles so is remote consult fixed position, find outside abandoning land namely with construction picket in same straight on-line two fixed position are nodded, will decide construction picket, contrast seriously picket the place that arranges a graph to decide construction picket to go up in blueprint and number, make good construction record.
The influence of CFG picket construction to circumjacent environment
The to circumjacent environment influence when picket of CFG of the pump pressure inside canal of long helix bore mixes material construction to be in saturated sandy soil and powdery earth layer into picket, cause the attention of people more and more, if this problem cannot get appropriate is solved, can restrict its to apply mediumly in layer of this cultivate land. The to circumjacent environment influence when picket of CFG of the pump pressure inside canal of long helix bore mixes material construction into picket, main show is the ground inside construction site to sedimentation, groundwater carries mud of arenaceous, belt, create circumjacent area or road surface and building metope break. Thinking through be being analysed to multinomial project example basically is layer element and construction element.
The influence of 1 layer
Saturated sandy soil and powdery earth are long helix bore the internal cause that picket of CFG of the pump pressure inside the canal mixes material construction to cause pair of circumjacent environments to affect into picket. The layer that Zhengzhou urban district has feature of earth of this kind of cliff distributings more it is Zhengzhou, below the earth's surface 0? The powdery earth inside 17m limits is easy dehydrate, easy be disturbed, have slight and liquefacient possibility, deepness 14m left and right sides is put in clay of weaker and organic matter. Limits inland leaves field water level is high, cent dives into superstratum and lower levels is tiny bear press water, this kind of earth suffers disturb easy generation liquefaction, generation shedding changes, cause draw near foundation earth to the flow inside aperture, make the ground sinks or earth of surface layer foundation has been out of shape big, rip road surface or all round the metope of the building.
The influence of 2 construction
When the chestnut inside canal of long helix bore presses CFG picket to mix material construction into picket, the course is taken to run the drilling tool into the well in drive drilling tool in, spiral ribbon is had to aperture week earth cut and oscillatory action, make earthy system liquefaction, hole water pressure is elevatory, when promoting drilling tool, pump action forms the brief vacuum status inside aperture, the system of the land inside certain limits is right now medium hole water all round bore carries seep of slimy arenaceous Xiang Kongzhong, thereby aperture week earth gradually to the flow inside aperture, expand to far. This kind of construction is in to the influence mechanism of surroundings construction site also got confirming in process of precipitation of light-duty well point, the water that before inside canal of long helix bore picket of pump pressure CFG mixes material construction to begin into picket, light-duty well point takes out is the clear water that contented precipitation asks, after CFG picket begins construction, the water that light-duty well point takes out is contain arenaceous bigger chaotic water.
Solve the main train of thought of the problem
The influence of construction of picket of 1) bright sheet to picket, the design reference that provides best picket span to design a section thereby is worth, choose right construction order to provide reference for construction unit.
Construction of 2) CFG picket is the same as base hole timbering project unites a consideration, make above all base wall of act of shut-off of water of picket of agitate of hole cement earth, what direct block breaks hole water seepage is convenient passageway, reduce the effect of CFG picket construction to circumjacent environment.
3) discusses the improvement of concerned construction parameter.
Easy generation blocks aperture of canal, change up in construction process, get into abandon land big, cause bore fixed position to forbid, construction is influential to circumjacent environment wait for a problem, put forward effective quality to control measure in the light of these problems, have to the construction of similar project draw lessons from a meaning. Should continue to strengthen the research of these pair of problems at the same time, raise the applied level of this craft thereby.
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