pile driving hammer energy calculation

GRLWEAP14s user-friendly interface includes more than 1000 preprogrammed hammers, extensive help, and numerous automatic features. Advantages of Single Acting (Open End) Diesel Hammers, Disadvantages of Single Acting (Open End) Diesel Hammers. Superior combustion chamber design and fuel delivery system provides industry leading energy transfer as well as easy starting on soft piles and in cold weather conditions. Oil Flow: 605 l/min 160 gpm These hammers have external power sources such as the crane, steam boilers, air compressors, and/or hydraulic power packs. A. PPENDIX . The way that the piles and the surrounding soils interact adds a level of complexity to the process, with the introduction of piles into the soil typically altering the character of the soil. The development of the steam hammer, use of concrete piles, and the creation of the first dynamic pile driving formula permitted even more efficient installation of piles. The challenging aspect of dealing with soil presents a variety of problems that can be anticipated. When Wave Equation Analysis is used instead of Dynamic Formulae, several codes and standards of practice allow a leaner foundation design translating to lower factor of safety or higher resistance factor. Increasing strokes in hard driving provide increasing energies. Pile-driving leads are used to align concentrically the pile head and hammer, provide lateral support for the pile, and maintain proper pile alignment and position during driving. These hammers increase the blow rate with a shorter stroke. Pile Type Hammer Energy Rating (ft-lbs) Number of Piles Strikes per Pile. The majority of diesel hammers manufactured today are the tubular, air-cooled type. Various clamp types to suit all pile types. The hammer cushion, which protects both the hammer and the pile from excessive stress. A restrike test is needed to determine changes in the soil strength. %%EOF If the blow count is different in the field, theres likely a problem. 0000013966 00000 n In a class by itself is the resonant pile driver, first introduced in the early 1960s. The Pile Driving Analyzer (PDA) system is the most widely employed system for Dynamic Load Testing and Pile Driving Monitoring in the world. I'm just perplexed that anyone would call for a driving criteria of 10 blows per foot and that the project engineer would agree. 2435 0 obj <> endobj A structural engineer will determine if changes in the driving system or pile depth are required. hi\J}p WeCX-e\=772MQCqN-27Ri|1R(UXUh8~HACz83u=R,*&+kQ!VyHQL*v+)+}Zqf^P[#?mvox'_=y{>;7O}vy_Wj?op}FoO>}}Oo?7WF>C 7_>}o|n_Ck?W//xFN~?W_7i/^2{T}? Metal 3D printing has rapidly emerged as a key technology in modern design and manufacturing, so its critical educational institutions include it in their curricula to avoid leaving students at a disadvantage as they enter the workforce. 0000005743 00000 n As well, soil particularly in a large area can vary greatly. It could also remove the plug from the pile while driving. Max Amplitude: 32.7 mm A hydraulic hammer incorporates the use of an external energy source to lift the hammer to the top of its stroke. A = concrete pile, 75 mm packing under helmet, B = concrete or steel pile, helmet with dolly or head of timber pile. High blow rate compared to open-end diesels. The comparison of these two results demonstrated that impact-vibration driving is substantially more efficient in terms of maximum driving depth and pile installation speed. 0000008195 00000 n It is important that the helmets striking surface is smooth and contacts the pile top evenly. Selection of a hammer should consider the anticipated driving resistance, ultimate capacity, pile stresses expected during driving, and soil set-up. High eccentric moment and vibration amplitude. 0000005436 00000 n Applying the modified ENR formula brings to Applying the factor of safety gives C) Before applying the Danish formula, we compute the term so that Steam (and later compressed air) was used in these hammers to accelerate the ram downward with more force than gravity alone would provide. If you must get guidance from a true expert,contact Dr. Dave Rempe in Champagne, IL (he's the guy I use on pile jobs). Hammer coefficient is given in Table 1. Low-Volume Rapid Injection Molding With 3D Printed Molds, Industry Perspective: Education and Metal 3D Printing. Through the 1950s and after, the Soviets developed a variety of vibratory pile-driving hammers and soil drilling equipment. These hammers burn the fuel that powers them inside of the hammer itself. The Romans accomplished planners of infrastructure also used driven piles to support military and civil works. They are categorized by how they attach to the pile driver - hanging, fixed, or swinging. Uncertain energy when combustion prevents ram-anvil impact. Estimating Driven Pile Capacities During Construction. However, if your calculations indicate low stress, there are several potential causes. Centre Width: 0.330 m 0000002992 00000 n From the dawn of human history, driven piles were used to raise a shelter above the water or land. There are of two basic types. 11916 Missouri Bottom Rd. Pile driving is a critical part of the construction process. This system will use emerging connected and automated vehicle applications like predictive approach and departure at traffic signals, efficient adaptive cruise, and optimized stopping and . Length: 126 (319 cm) Preparation and contingency planning are the key to keeping a pile driving project on track and on budget. Leads keep the piling and hammer aligned. As a result, fewer piles and smaller footings could be used for the same load when using concrete piles (as compared to timber piles). Notify me of follow-up comments by email. Driving system problems can be related to low hammer efficiency or cushion that is too soft. GRLWEAP14 is the pile driving simulation software of choice worldwide for pile driving professionals: Simulates the pile response to pile driving equipment. It is guided by columns or inside guiding enclosure. Energy output is very sensitive to proper valve timing, and to pressure and volume of the motive fluid. First ensure that the driving system is matched to the pile type. Use them with banding near the top of the pile to prevent splitting. This formula also considers factors such as tension stresses in concrete piles, the effect of ram weight, and the impact of hammer cushion stiffness and drive cap weight. Instead of attempting to broadly characterize pile behavior, it makes more sense to work to understand the factors that influence the successful design of pile foundations. A pile driver is a heavy-duty tool used to drive piles into soil to build piers, bridges, cofferdams, and other "pole" supported structures, and patterns of pilings as part of permanent deep foundations for buildings or other structures. observing the soil resistance to piles during the driving process. First, steam replaced human power to turn the winches which drove the piles. Since 1984, Pile Buck has provided the deep foundations and marine construction industries with news, tips, stories, and supplier information. The recommendation was drive to 25bpf, which was within the range of the WEAP analysis. There are several problems that can arise in the field. Steam hammers came into use in the United states after 1875. The soil could have greater strength, higher damping ration, or larger soil quakes than initial testing anticipated. Hammer mass: 5500 kg, Claydon Business Park, Gipping Road, Great Blakenham, Ipswich, Suffolk, IP6 0NL. Hn6s)zn ]^t]Y2(EAYE.|w?. %%EOF Lower soil resistance or better hammer performance. While this model allows for superior cooling capability, they are inconvenient to use. Trip assembly includes safety mechanism to prevent unintended engagement during operation. using a variety of specialized clamp attachments. Be aware of reductions in actual hammer energy. The "Delmag" name has become synonymous with high performance and ruggedly reliable equipment. The vertical advance of a pile under a given hammer blow is used as a measure of the piles bearing capacity. Attach drawings to your e-mail: H-piles were used as a way to address problems that occurred with the use of I-piles. When the angle is horizontal, GRLWEAP may be used to simulate the installation of culverts. 64 0 obj <> endobj Impact Block approx. Steel These piles had steel wings that linked the piles together and pile caps were used between the pile and the hammer which possibly increased the number of total strikes per pile. The leader mast serves as a guide for the attachments, and is available with stroke up to 82 feet. hb```f````a`` @1V xl)U/NfTQQn Ramcw#2t'r)>, 0 Pa` Higher rate of blows per minute than drop hammers. The mandrel is necessary because the pile wall is too thin to withstand the stresses of driving. Deep obstructions can reduce calculated bearing capacity. Height w/o Clamp: 81 (207 cm) Cleveland, OH 44139 USA Recommended in projects requiring a high driving or extracting force. PEinc This is a very interesting question. Pile-driving is an important construction technique that is used throughout the world. of energy as well as many other popular models for more typical piling projects. In 1845, Scottish inventor James Naysmith developed a steam hammer that was used to drive piles at the Royal dockyards in Devonport, England. The HPSI Model 500 is adaptable to any type of pile (pipe pile, steel sheet pile, h-pile, king pile, concrete piles, etc.) Delmag Rh 28 Drill RigLearn more about the Delmag Rh 28 Drill. A properly functioning hammer strikes the pile in quick succession. Our range of vibrodriver H/HD with standard frequency and fixed eccentric moment. The hammer ratings vary from 5 to not more than 80-kip-ft, with ram sizes between 1 and 10 kips. Or increased driving system performance. The first impact-vibration hammer was built in the Soviet Union in 1949. The lead, also called the set of leads, sometimes including a brace that allows for the adjustment of the lead angle. Combined with the soil parameters selected in the actual project, the pile end resistance, sand dynamic side friction resistance, and clay static friction resistance of each layer of soil in the pile driving process of steel pipe piles are calculated using ()-().From the calculation results in Table 2, it can be seen that the pile end resistance received by the pile body in the sand layer is . In the twentieth century, greater driving force was achieved by using air- or steam-powered machines to accelerate the rams downward action. This rate is comparable to most other hammer types that lack downward assist. Since 1984, Pile Buck has provided the deep foundations and marine construction industries with news, tips, stories, and supplier information. Reduced fuel should only limit how "hard" the hammer hits at practical refusal. Example 1: Calculation Of Minimum Hammer Energy E-13 Example 2: Calculations For Establishing A Blow Count Chart E-14 Example 3: . Even with reduced fuel, this hammer can probably deliver 19,000 ft-lb (5.5 ft stroke) that the pile is "calling for", and it will do so. The study led to the development of a series of charts, which could then be used to estimate pile stresses and resistance for concrete piles. After World War II, mechanical engineer E.A.L. As a construction method, pile driving has existed since before humankind was literate. Smith of the Raymond Concrete Pile Company developed a numerical method to model stress waves in piles and pile behavior. In 1969, the Americans introduced their first hydraulic vibratory hammer, the MKT V-10. The stroke of a pile- driving hammer is usually between three and ten feet (900 to 3000 mm). 100 0 obj <>stream All components of the driving system have some effect on the performance of a hammer and/or how the hammer transfers its energy to a pile. The heart of this system is a slewable all-direction telescopic or fixed leader mast mounted to a special carrier. The Journal of the . This is a com-mon practice allowed by OSHA. Pile Clamp Force: 200 tons To successfully translate the pile design into construction, the engineers must rate the requirements of the static analysis methods, the dynamic methods of field installation and construction control. Weight: 6,200 lb. Calculate pile length, capacity and performance. 0000009574 00000 n GRLWEAPcontinues to be the software of choice for industry-leading piling professionals around the world. It is typically made of several layers of plywood. For a given hammer, varying the drop height can vary the energy per blow. A closed end diesel hammer consists of a long slender piston (the ram), which moves inside a cylinder. Height: 75 in (1905 mm) Hoisting allows air to flood into the cylinder, or pile, below. The primary advantage of these machines is their lowered transmission of ground excitation to neighboring structures. Close this window and log in. It transfers a large portion of the kinetic energy of the ram into the pile. Vertical columns made of various materials (wood, concrete, steel, or a combination) are driven into un-excavated soil. 867 0 obj <> endobj The ability to drive the pile without structural damage or reducing soil capacity. The piles were installed by driving (hammering and vibration) and boring techniques. Max Frequency: 25 Hz / 1500 rpm In the final stage of the pile's embedment,On the bases of rate of settlement, it is able to calculate the design capacity of the pile. Sounds like we all pretty much agree. 0000124205 00000 n One example is a when the field stroke of a diesel hammer is less than 90% of the calculated stroke. You will need to do restrike testing in the case of lower soil resistance. Shortly thereafter, American A.A. Raymond used concrete piles for the first time in the United States while constructing a building foundation in Chicago. Optional ABI Customer Portal, 11916 Missouri Bottom Rd Hazelwood MO 63042. GRLWEAP Offshore Wave Version includes exclusive features designed for challenging situations (free riding hammers, nonuniform and battered piles) and special analysis options such as fatigue output tables. endstream endobj 68 0 obj <>stream E-D. RIVEN . The applied hammer energy output is sensitive to soil resistance. 83 0 obj <>/Filter/FlateDecode/ID[]/Index[64 37]/Info 63 0 R/Length 97/Prev 183421/Root 65 0 R/Size 101/Type/XRef/W[1 3 1]>>stream Pipes were used as piles in two different ways. They are categorized by how they attach to the pile driver hanging, fixed, or swinging. For the protection of the pile top against a compressive damage, thinner cushions are usually sufficient. Thanks. While the method of driving piles has evolved considerably, the same basic technique is still used to achieve the goal of installing a pile into the ground. The relation suggested by Janbu for ultimate capacity of the pile is: E = Modulus of elasticity of pile material. Wooden piles would continue to be used until the end of the nineteenth century. Shipping Width: 85 in (2159 mm) This pile simulation and analysis allows the user to investigate which hammer is likely to be sufficient and economic for a certain pile and soil condition prior to mobilizing the hammer to the job. & 1I`w@h>Ql3*ca:z+^K_eoL*[6[k`Rf~)T_D->2[LhsW{=n8h# ~/-sI+&N_{5[yM2ev$lkQdg;Eh17|5NzuxM;vO9:d,Fxt7L%o]wXwoe{}c~n'{bvJ='bQj'x0. A detailed investigation into the validity of pile driving formula suggests that there is little to choose between the Hiley and Janbu formula. However, the failure of soil in an adjacent slope could be the cause. In fact, driven piles are the oldest type of deep foundation. Quick and safe set up from transport mode to working mode and back can be accomplished with ease utilizing the ABI docking system. 0000009843 00000 n %%EOF Forget it. The hammer ratings vary from 5 to more than 300 kip-ft with ram sizes between 1 and 35 kips. Perhaps the overall concern is with pile extraction re - It will keep going until it runs out of fuel or is manually stopped. Please let us know here why this post is inappropriate. I'm not saying you are wrong, just that you are in the minority so far. Weight of piston approx. 0000106027 00000 n The impact block separates from the ram within a very short time and the pressure of the combusting air-fuel mixture will cause further separation as the ram is forced upward. If it is taking a lot more blows to drive the pile than planned, there is an issue with the soil and / or the driving system. By joining you are opting in to receive e-mail. Traditional Pile Drivers. In the late 1800s, a French engineer introduced concrete piles in Europe. 0000004140 00000 n Already a member? Driving Force: 53 tons (472kN) Today, OMS is among the companies leading this sector with the in-demand products. When it comes to pile driving, a hammer isnt just a hammer. We do not see a significant exposure with this as the weights of the hammer, leads and piles can be easily determined by calculation, name plates, manufacturer's literature, weighing and other factors. In addition, it models the pile as one rigid mass. A stone block would be lifted by ropes, which were stretched taught by humans and arranged in a star pattern around the pile head. Max Line Pull: 133 tons (1,183 kN) Of note is the Uraga hammer, which involved the placement of an electric motor inside of each eccentric. If previously installed piles move laterally when new piles are driven, soil displacement is the likely culprit. Driving piles allows a structure to be placed in an area that would otherwise be unsuitable given the subsurface conditions. Sign up here. Amplitude: 1 in (25.4 mm) Pile Master Air Hammers originally built for the dock building industry are designed for driving timber, h-pile, pipe, and prestressed concrete piles. Full support for installation, maintenance and repair needs. These piles are driven, pushed or otherwise installed into the ground. 0000002370 00000 n Another possible cause is a combined tension and bending that is too high. Developed for deep underwater pile driving up to a depth of 2000m, they can be used for all offshore piling jobs, including driving pipeline initiation pile, piles for jackets, conductors and mooring systems. DIMENSIONS: Removing the obstruction will shift the soil and may reveal other soil issues beneath. Typical drop heights are approximately 4 (1.2 m). Width: 388 mm, 1058 Roland Avenue Green Cove Springs, FL 32043. These are hammers with a vibratory frequency of 10 to 30 Hz, used for piling such as sheet piles and small pipe piles. Damage to the pile due to overdriving must be avoided, both when penetrating an overlying hard layer and when driving into the bearing stratum to develop the full healing capacity. The wave equation or stress-wave theory addressed many of these issues. Determining the right design is difficult. If you dont have it, will be happy to email it. This is only needed on concrete piles. There are two key reasons for a lower-than-anticipated blow count. Smaller models also allow for easy transport and compact jo sites. Inspection of pile installation ensures that the load bearing capacity anticipated during the design phase of the project is achieved. As per the Engineering News formula the allowable load of driven pile is given by: Where, Q a = Allowable load in kg W = Weight of hammer h = Height of fall in cms s = Final settlement per blow known as set c = Empirical constant (c = 2.5 cm for drop hammer and 0.25 cm for single acting and double acting hammer) Select driven pile type based on the use of formulas and in consideration of the structural capacity of a pile, the geotechnical capacities of the pile type for the soil conditions at the site, the capability of available contractors, and cost. This facilitates driving and extracting. Hose Bundle Length: 100 ft (30 m) 2482 0 obj <>stream Find out which version of GRLWEAP is right for you. C. ALTRANS F. OUNDATION . : 14,065 lbs The dynamic formula fails to take into account the driving system and the soil as it interacts with the pile. A hydraulic hammer incorporates the use of an external energy source to lift the hammer to the top of its stroke. endstream endobj 2436 0 obj <>/Metadata 99 0 R/OutputIntents 2432 0 R/Pages 2427 0 R/StructTreeRoot 139 0 R/Type/Catalog/ViewerPreferences<>>> endobj 2437 0 obj <>/ExtGState<>/Font<>/ProcSet[/PDF/Text/ImageC/ImageI]/XObject<>>>/Rotate 0/StructParents 0/Tabs/S/Type/Page>> endobj 2438 0 obj <>stream This includes an understanding of how the pile will interact with the soils (geotechnical engineering), the dynamics of moving bodies (engineer mechanics) and the stresses during driving and after installation (structural engineering). In a class by itself is the resonant pile driver, first introduced in the early 1960's. The central principle of the resonant driver is to induce resonant response in the pile. Hydraulic Power: 304 kW / 413 HP Temporary compression of the pile is used as a proxy of hammer energy and dynamic soil response in the Hiley formula. Width: 590 mm 23 in First, they could operate without an external power source. There are two prominent manufacturers of closed end diesel hammers distributing their products in North America: Bermingham and MKT Geotechnical systems. Overall length: 4300 mm = 0.4 for difficult or bad driving conditions. Total Weight W/O Clamp: 6150 kg 13559 lbs This hammer and ones that followed became the most popular types of steam hammers in the United States. If they are matched, make sure the driving system operation conforms to the equipment manufacturers guidelines. The hammer is raised to the desired stroke. If you encounter shallow obstructions within three feet of working grade, you can likely just remove it without significant impact to the surrounding soil. Eccentric Moment: 5,000 in. We have received your request and will respond promptly. At a high level, a pile driving system has four main parts: lead, hammer cushion, helmet, and pile cushion. The direction, location, and severity of the cracks provide clues to the cause. Appealing to the ENR formula, we have Applying the factor of safety gives B) The weight of the pile + cap ensemble is = 9 + 2.4 = 11.4 kip. Diesel hammers were first introduced in the United States after the Second World War. Common problems with concrete piles and solutions include: Where easy pile driving causes partial horizontal cracks in a concrete pile, check the hammer-pile alignment. Hammer selection is the most important aspect of pile installation. Over time, Americans have developed a unique type of vibratory hammer with slim throat hammers for sheet pile driving, hydraulic drive, and high power engines, pumps and motors. Beyond the dynamic formula, field monitoring techniques can also be used to understand pile dynamics. It should have a similar energy rating and ram weight. The VPM-170 could drive pile pipes of 1600 millimeters in diameter into any type of soil other than rocky soils. 326 0 obj <>/Filter/FlateDecode/ID[<2A84DAB0928AC74EB2312F9B49A745B4><96E3DD0E2FEE8D4D9EA5AB2195EC0CE5>]/Index[312 25]/Info 311 0 R/Length 76/Prev 69020/Root 313 0 R/Size 337/Type/XRef/W[1 2 1]>>stream Since the ram falls only under gravity, the OED is also called single acting. If too low, quakes are likely higher than expected. Evaluate information and select foundation system: use the information gathered above to make a determination about the proper foundation system. There were two types of these kinds of hammers. the hammer mechanism may greatly reduce the actual energy delivered to the pile during driving. When using a wave analysis software program to predict pile behavior, you may run into data issues. BSC111, looks like you are the first to agree with the 10 blows per foot. 0000001276 00000 n Care should be taken to avoid excessive driving, which can lead to pile damage and/or foundation cost overruns. (Something that should be done before the work is started.) In this situation, pre-drilling of pile locations can be employed. The resulting formula could then be applied to the work at hand. In fact, one of the oldest bridges in Rome was named the Pons Sublicius, which means the bridge of piles. The ability to obtain penetration rates within the desired band. Pile Buck is published every two months and is distributed internationally. The ram is usually a short, stocky block of steel that is connected at its top to a piston. 0000003742 00000 n PILE BUCKS TOP RECOMMENDED IMPACT HAMMERS AND VIBRATORY DRIVERS. Others use a purely hydraulic system to control the valve and thus the cycling of the ram. This includes interaction between engineers during the design state, consulting with experts, and talking directly to drill crews and laboratory personnel. 0000064415 00000 n ADOT must implement pile driving soft-starts whereby hammer energy is gradually ramped-up ADOT must employ at least three PSOs to monitor the harassment zones; ADOT must submit a draft report detailing all monitoring within ninety calendar days of the completion of marine mammal monitoring or sixty days prior to the issuance of any subsequent . Drop hammers are typically used on very small projects and for small piling. 0000002455 00000 n Centrifugal Force (Max. Alternatively, the measured peak velocity of the pile can provide an indication of energy imparted. Over the years, technology has advanced toward the development of larger and faster hammers. hXmo(+| "[n]OMcGW6J'f`f`P"cb(I C!I$Q3(ar@&UDT"cU)I a11c`TUJ`c{Ya`VqV-M& seCh0 u]SN`p8 qn}&? \G]5$3i7!C=jl!VZ\Hh!!7<>N0K3;y}(+tUDcUo__FnUU/4"mfE>? Single acting or drop-hammer or diesel-hammer, Helmet with composite plastic or Greenheart dolly and packing on top of pile, Helmet with timber dolly (not Greenheart) and packing on top of pile, Driving cap with composite plastic or Greenheart dolly, Driving cap with timber (not Greenheart dolly). It seems to me that 10 bpf are too few to know how well the pile capacity is developing - so are your 25 bpf. Thanks for your reply, Riggly. Delmag has long been the world-leading manufacturer of diesel pile hammers and continues to develop new products and features. Throat Width: 22 (56 cm) It could also operate in two different frequencies. Many attempts have been made in the past to determine the relationship between the dynamic resistance of a pile during driving and static load carrying capacity of the pile. The helmet distributes the blow from the hammer more uniformly to the head of the pile to minimize pile damage. Title 24 Calcs is a service provider of the California Title 24 energy compliance, we provide Title 24 compliance services for residential and commercial buildings-Submit your Project 657-234-0134 projects@title24calcs.com Once mobile crane rigs came into existence, the use of skid rigs stopped. Janbu formula gives e slightly better correlation between tested and calculated bearing capacity. 915 0 obj <>stream Throughout construction, knowledgable engineers should supervise and inspect the installation of the piles. Relatively low ram weight compared to energy (high strokes.). Using these hammers, piles were driven into medium-firm sandstone to construction an anti-filtration wall under the dam. The ram must have a mass and impact velocity that is sufficiently large to move the pile. Throat Width: 13 in (330 mm) Single acting air/steam units from Vulcan and Menck are commonly used to drive piles offshore. %PDF-1.4 % The need to use pile penetration rate as the means to end driving. xref This requires establishing the setup factor and driving to a lower capacity. I downloaded this document in .pdf format some time ago, but it no longer seems to be available. The VU-1.6 could drive the same size of pipe to depths up to 30 meters. Established in 1987, OMS has mastered the design and manufacture of vibratory pile driving/extracting machines, hydraulic power packs, hydraulic clamps, and soil improvement equipment. St. Louis, MO 63042, Web Design by Captiva Marketing | Privacy Policy | Site Map, Cookies are used to enhance your viewing experience. During construction, all parties should continue to communicate so that they can resolve any construction issues as they occur. As the manufacture of concrete became more advanced, the use of concrete piles became more prevalent. In addition, pile drivability should be considered during design, as large costs may be generated if the piles that have been selected and planned for cannot be driven. The initial impact-vibration hammer was welded to the top of a metallic tube, and the hammer then drove the rube into a variety of soils. Axuiliary Winch: 11,240 lb f. Helmet Advantages of Single Acting Air/Steam Hammers, Disadvantages of Single Acting Air/Steam Hammers. 0000050413 00000 n These are vibratory hammers with a vibratory frequency of 5 to 10 Hz, used primarily with piles which have high mass and toe resistance such as concrete and large steel pipe piles. Amplitude: 1.12 in Design satisfactory: review all aspects of the design and make changes as necessary, Prepare plans and specifications, set field capacity determination procedure. If they are similar, use lower combustion pressure to align the hammer stroke. The impact-vibration hammer was first used in the construction of the Stalingrad (now Volgograd) power plant.

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