KNOW THE DIFFERENCE BETWEEN MECHANICAL AND HYDRAULIC VALVE LIFTERS

I personally have a love-hate relationship with valve lash adjustment. I love adjusting anything mechanical, getting my hands on it and fine-tuning it to perfection.

The part that I hate is how awkward, burdensome, and complex it often is to get to the lash adjustment. It seems that half of the engine and its accessories need to be removed to perform a 10-minute valve lash.

For this reason, I like engines with hydraulic valve lifters that, for the most part, require no adjustment. If the valve cover never has to come off an engine, that is a good day for me.

There are times when the hydraulic valve lifter needs to be adjusted. But instead of setting lash (as you would with a solid or mechanical valve lifter), a hydraulic system needs to have the preload set since there is no lash. This is usually only required if the cylinder head has been removed and is now being reinstalled.

THE NEED FOR SETTING LASH
The camshaft in an engine is responsible for the timing, lift, and the duration the valves stay open and closed. To accomplish this, it works through the intermediate components of the valve lifter (or tappet), pushrod, and rocker arm (in a cam-in-block engine).

With an overhead cam design, the intermediate components are different using some style of follower in lieu of a pushrod and possibly a tappet. This guide will be focused on a hydraulic tappet employed in an engine that has the camshaft in the block.

Read more: KNOW THE DIFFERENCE BETWEEN MECHANICAL AND HYDRAULIC VALVE LIFTERS

Matching Seals to Dynamic Sealing Applications

Successful sealing of fluid power cylinders requires a delicate balance of interrelated factors that affect the sealing process in a dynamic system. These factors include lubrication and mating surfaces; design factors, such as shape, material, and process; and environmental factors, such as pressure, temperature, time, dynamics, and assembly.

Understanding the role of lubrication is the first key to successful sealing in dynamic systems. A fully lubricated system will experience some leakage, usually in the form of a fluid film, but friction will decrease, leading to a corresponding decrease in seal wear. Not surprisingly, the opposite is true: In a sparsely lubricated system, the fluid film decreases, but friction—and thus, wear—increase.

Moreover, sealing tends to improve as fluid pressures increase. Because system pressure on the seal surface compresses the seal axially, the seal is forced more tightly into the gland, improving conformability of the seal with the metal surfaces around it. If the seal is correctly designed, as system pressure increases, sealing force and effectiveness also increase.

A seal’s ability to resist extrusion is a third key factor. Seals in dynamic systems must resist shear forces resulting from the differential between the pressurized and unpressurized sides of the seal. Shear forces tend to push the seal into the gap between adjacent metal surfaces (known as the clearance gap), and the seal material and profile must be sufficiently strong and stiff to resist being damaged or destroyed.

Rod Sealing
Leak-free performance and high service life cannot be ensured by a single sealing element in heavy-duty applications. Because the cylinder’s piston rod is directly exposed to the environment, it’s paramount that the seals keep the fluid in the system. External leakage is easily noticed. Not surprisingly, then, it has become a common criticism of hydraulic power transmission.

Read more: Matching Seals to Dynamic Sealing Applications

GOMACO to Unveil GT-3600 Curb, Gutter Machine at World of Concrete

GOMACO’s new Xtreme GT-3600 curb and gutter machine will be displayed for the first time ever in GOMACO’s booth in the Central Hall at World of Concrete 2019. The GT-3600 was the first three-track machine to slipform a 24-in. radius, and now, with the Xtreme package on board, tight-radius paving is easier and more efficient than ever before. The Xtreme package adds G+ radius software with slew drives, smart-sensored hydraulics and intelligence to the GOMACO GT-3600.

Xtreme steering and ultimate intelligence have been added to each of the GT-3600’s three tracks and include rotary-sensored slew drives, sensored All-Track Steering and All-Track Positioning, and smart hydraulic cylinders. The Xtreme GT-3600’s tracks can now rotate farther than ever before. The smart cylinders allow the G+ control system to know the exact position of all three tracks so it can make steering adjustments as needed. It’s the ultimate in finite and accurate machine control.

The first three-track slipform curb and gutter machine to slipform a 24 in. radius now features GOMACO’s Xtreme Radius program for tight radii on stringline. The G+ radius software allows the operator to program the size of the radius into the controller.

G+ calibrates and manages all the aspects of traveling around the radius, including track angles and individual variable track speeds. As the Xtreme GT-3600 approaches the radius, with the values already dialed in, the operator activates the radius program, and the machine slipforms around the radius. It’s that easy for any operator to pour a curb and gutter radius. The individual track speed control provides smooth machine travel around the radius. The G+ control system also easily interfaces with any of the major 3D guidance systems for the same smooth control.

A smart hydraulic cylinder also is utilized for intelligent offset when telescoping and sideshifting the mold mounting system. The smart cylinders provide G+ the ability of repeatable mold offset. The trimmerhead and mold also have independent vertical adjustments for raising and lowering to work around job-site challenges.

The Xtreme GT-3600 is equipped with the latest in Tier IV technology. Along with Tier IV is a new optimized cooling package with a hydraulic fan controlled by G+. G+ adapts the cooling needs to individual jobsite conditions for a quiet and efficient operation. Fuel efficiency also has been optimized and combined with an increased fuel capacity for an uninterrupted day of paving. The Xtreme GT-3600 also is available with GOMACO Remote Diagnostics (GRD) for machine troubleshooting, diagnostic reviews, software updates, and more.

Read more: GOMACO to Unveil GT-3600 Curb, Gutter Machine at World of Concrete

Kalmar Forklifts Delivered to ENTP

The marine industry equipment manufacturer Kalmar has delivered a total of 18 forklift trucks to Algeria’s leading drilling contractor Entreprise Nationale des Travaux aux Puits (ENTP).

According to a press release from Kalmar, part of Cargotec, the company  will also support ENTP with parts supply and provide operator training to their staff. The machines, ordered in the first quarter of 2018, were delivered during the third quarter.

Established in 1981, ENTP is the leading drilling contractor in Algeria with a market share of close to 45 percent. The company performs drilling and maintenance operations on both deep-water and hydrocarbon wells across Algeria.

ENTP is a subsidiary of Sonatrach, which is Algeria’s largest company in terms of both turnover and number of employees. The Kalmar forklifts are deployed at the company’s site in Hassi Messaoud, Ouargla in eastern Algeria and have a lifting capacity of 14 tons.

Kalmar G-Generation forklifts are designed to offer customers the best possible return on investment over the lifespan of the machine. They are ideal for demanding applications such as handling heavy, bulky loads such as a section of pipe or pieces of drilling equipment, and combine low fuel consumption and superior lifting performance with easy maintenance and excellent reliability.

A variable hydraulic fan keeps the engine and hydraulics cool even in the most extreme operating conditions, which was was a key factor in ENTP’s decision to choose Kalmar machines. Also important was Kalmar’s ability to adapt the machines according to the customer’s unique requirements, which included fitting the machines with a spark arrestor system to prevent any sparks from the machine’s engine from accidentally igniting flammable materials in the immediate vicinity.

Read more: Kalmar Forklifts Delivered to ENTP

The Four Pillars of Hydraulic Machine Efficiency

Most readers of this column are well aware that the viscosity of a hydrocarbon-based hydraulic fluid is inversely proportional to temperature. As temperature increases, fluid viscosity decreases and vice versa. This is not an ideal situation for several reasons. In fact, the ideal hydraulic fluid would have a viscosity index (the change in a fluid’s viscosity relative to temperature) represented by a horizontal line intercepting the Y axis at 25 centiStokes.

This temperature-viscosity shows that an ideal hydraulic fluid would exhibit no change in viscosity regardless of temperature.

Unfortunately, no such fluid exists for hydraulic machine efficiency and longevity. And it’s unlikely such a fluid will be developed in my lifetime. But if such a fluid was developed and patented, its creator would hold the key to a gold mine. For now, we have multi-grade hydraulic oil. These fluids have a high viscosity index, so their viscosity is less sensitive to changes in temperature than a monograde oil.

Unintended Consequences
Fluid viscosity is one of the factors that determines whether full-film lubrication is achieved and maintained. If load and surface speed remain constant, but elevated operating temperature causes viscosity to fall below that required to maintain a hydrodynamic film, boundary lubrication occurs; this creates creating the possibility of friction and adhesive wear.

On the other hand, there is a viscosity range where fluid friction, mechanical friction, and volumetric losses are optimal for hydraulic system performance. This is the viscosity range where the hydraulic system will operate most efficiently: the highest ratio of output power to input power.

 

Read more: The Four Pillars of Hydraulic Machine Efficiency

Product roundup: John Deere upgrades compact wheel loader line

John Deere recently announced the redesign of its K-Series compact wheel loader models with the introduction of the 244L and 324L compact wheel loaders.

The company says these models are ideal for landscape/snow removal, ag material handling and construction tasks.

“Our next generation of compact wheel loaders was designed to meet the needs of industry professionals who are demanding higher performance from their machines,” says Drew Miller, product marketing manager, compact wheel loaders, John Deere Construction & Forestry. “Tailor-made for tight spaces, the 244L and 324L use our proprietary articulation plus system to provide greater stability and yield more lifting power while turning tighter.”

Read more: Product roundup: John Deere upgrades compact wheel loader line

Heavy hydraulics

In the second of two articles, Stuart Anderson, president of Chortsey Barr, assesses current demand for heavy duty crawler cranes, and looks at the important innovations made by Japanese manufacturers.

Over the course of time, demand for heavy duty crawler cranes can fluctuate quite dramatically according to the demands of large construction projects. However, in recent years we’d estimate average annual demand in the range of 300–350 units worldwide. Of this we’d estimate that the established European and Japanese manufacturers contribute approximately 200 units and the Chinese and Russian manufacturers around 100–150.

The typical Japanese and particularly European cranes are of significantly higher capacity than other competitors and therefore generate substantially higher average revenues. In contrast the Chinese cranes are normally quite small, lower-capacity units with relatively-low sales prices. Consequently, the European and Japanese cranes probably constitute some 80% or more of total revenues.

In the early days the first fullyhydraulic crawler cranes were quite small machines. Sennebogen’s first fully-hydraulic crawler excavator/ crane introduced in 1969 was the 15t capacity SK 15. Powered by a 105hp diesel it was available with dragline or grabs of 600–800l capacity. The previous year PPM, then a division of the leading hydraulic excavator manufacturer Poclain, had introduced the its first fully-hydraulic crawler excavator/cranes in the shape of the 12t capacity model 12.02 available with dragline buckets of up to 700t capacity. PPM went on to sell over 400 hydraulic crawler excavator/cranes.

However, in terms of product development, throughout the 1970s, it was really Hitachi and Sumitomo that made the running. By the end of the decade these Japanese manufacturers offered fully-hydraulic crawler excavator/cranes of up to 150t capacity. Their machines, especially in the small-to-mid size classes, became immensely popular both at home in Japan but also throughout Asia, Australia and Europe. While most of these were not ‘heavy duty’ crawler cranes, all were capable of performing as draglines, grab cranes and pile drivers as well as straight lift cranes. Arguably Hitachi was the mostcommitted to fully-hydraulic cranes while Kobelco, Sumitomo, IHI and Nissha continued for some years to rely on the heavy-duty versions of their big mechanical crawler cranes for duty cycle and foundation work.

Read more: Heavy hydraulics

New Enerpac hydraulic gantries

The new products offer lifting capacities and accurate load positioning from 100t (110USt) to 200t on a narrow 610mm track gauge.

They feature two stage lift cylinders, with the SL100 having a maximum lifting height up to 4.75m (15ft) and the SL200 6.7m. Typical industrial moves applications include: transportation and installation of presses, machine tools, electrical transformers and injection-moulding machines.

“Designed for safe lifting in confined or limited-access spaces, the new SL gantries are easy to mobilise and demobilise and include self-contained hydraulics allowing quicker and safer deployment,” said Enerpac.

Each gantry leg features self-propelled wheels for travel along the narrow-gauge track together with an Intellilift synchronised control system, providing wireless control, unrestricted operator position, and automatic synchronisation for lifting/lowering and traveling.

“With significant growth in a number of industrial sectors, the SL100 and SL200 models were designed to meet the need for greater lifting capacities and new applications,” said Peter Crisci, product line director for Enerpac’s Heavy Lifting Technology product line. “We continue to evolve our lifting systems to enable new solutions for our customers facing ever more diverse and challenging applications.”

Additional components and accessories are available such as header beams, lifting anchors, side shifts and skid tracks. There are also tarpaulin covers, transport frames for side shift units, slings and shackles.

All of Enerpac’s gantries are CE & ASME B30.1 compliant and tested at maximum capacity at maximum extension and under witness of Lloyd’s Register.

Read more: New Enerpac hydraulic gantries

 

The evolving compact excavator: New ways to use this lower-cost, multipurpose tool

Though still used for just excavating, compact excavators are being deployed on a variety of tasks, as owners seek greater value from these versatile machines.

Some compact excavator owners are getting inventive and OEMs are getting inventive, too.

Volvo offers a Steelwrist tiltrotator, with plus-and-minus 45 degrees of tilt and 360 degrees of rotation, on excavators of 3.5 tons and over.

John Comrie, Volvo Construction Equipment product manager, says many Volvo customers find “they can do a lot more with a combination of a skid steer or mini track loader paired with a mini excavator, than with one mid-sized backhoe.”

The ability to rotate 360 degrees gives compact excavators greater versatility than backhoe loaders while offering comparable digging and lifting performance and the ability to use a full range of tools and attachments, he says. Backhoes have enjoyed the advantage of higher travel speed, but Comrie points out the Volvo EW60E wheeled compact excavator can now reach 19 mph.

“In the smaller size class, it’s rare to see just a machine and a bucket,” says Todd Dohnal, dealer development manager for Kobelco USA. “Typically, the unit will have an array of attachments.”

“Excavators do not just dig holes these days,” he adds. “They have become one of the most versatile pieces of equipment on the jobsite.”

Read more: The evolving compact excavator: New ways to use this lower-cost, multipurpose tool

Booms and Busts in Hydraulic Aircraft Seat Actuation System Sales Market

This market research report by Marketresearchpro Inc., has vast information about the Hydraulic Aircraft Seat Actuation System Sales market and its potential. The report is useful to everyone right from an expert, analyst, manager to an employee as it contains a variety of analytical and statistical data enabling the reader to have a complete overview and an in and out knowledge, which can be applied in the decision-making process concerning the core and crucial business areas.

How is this Report On Hydraulic Aircraft Seat Actuation System Sales Market Useful?

In order to comprehend the knowledge and insights received from this report, some illustration and presentation are also included alongside the data. These are in the form of charts, graphs, tables etc. Rather than reading the raw data, reading through tools is easier and more inferences can be drawn looking at these illustrative diagrams.

This report also helps the readers to get their hands on ready-to-access analytical data provided by the industry professionals. They can understand various vital trends, drivers, and challenges in the Hydraulic Aircraft Seat Actuation System Sales industry. This report will provide a detailed assessment of majorly the following:

Read more: Booms and Busts in Hydraulic Aircraft Seat Actuation System Sales Market

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