At a recent conference, a colleague from Chicago-based machine shop Bley LLC showed me pictures of the huge parts his team manufacturers. A gearbox front housing with torque arms, for instance, appeares over 6-ft in diameter. Main shafts are some 6-ft long and 2-ft in diameter with 5-ft diameter flanges on one end. Company manager Mike Milbratz says wind energy may be the only industry that needs parts at automotive cost and aerospace quality– inexpensive and high precision. His remark on quality also means wind turbine parts must be made or repaired by trained and skilled machinists. So how do you find such people?

“It’s a challenge,” he sighed. “If you know any send them over,” he added only half kidding. He explained that the most difficult positions to fill are for machine set-up tasks because of the years of experience needed. Milbratz says his shop keeps an almost permanent “help wanted” sign out. The situation is likely to worsen as older skilled labor begin to retire.

Deborah Picchione, HR manager for the Ohio region of machining firm Heroux Devtek echoes Milbratz comments, pointing out that the shortage for skilled metal machinists and manufacturing engineers is widespread. “Right now we have positions for manufacturing engineers, quality engineers, and lean manufacturing experts,” she says. All four of Picchione’s facilities carry on with unfilled skilled machining positions. In response, she keeps job ads on Career Builder, Monster.com, Linkedin, and other sites, and maintains contacts at nearby colleges and vocational schools.

Milbratz says his shop has a small training program to move people up the ranks, but a 60-person company cannot afford to train people in the basics. He relies on local community colleges for recruits, and hunts for talent at job fairs. Picchione says her company started an internship with computer-based training in CNC machining and print reading for new hires before they graduate to the shop floor and OJT. Starting salaries for people right out of a community college is about $15/hr, about $30,000/yr, and top out at least $27/hr. and above. Picchione points out that overtime, bonuses, tuition reimbursement, and benefits make a six-figure income possible.

So why in an era of over 9% unemployment (and probably more) does a career with decent pay, almost guaranteed employment, and respect, go begging for workers? There are several theories. One is that the skilled trades are not promoted in schools anymore. In the ‘60s and ‘70s, high schools had machine and metal shops along with drafting classes. These are mostly gone. The emphasis is on college. Those who do graduate from vocational schools snatched up quickly or do not stay with the trade. Maybe kids don’t want to get their hands dirty? Maybe they don’t realize the machine tool is a computer peripheral, and although the job can get dirty, it’s a lot cleaner than it once was?

The obvious solution to the shortage is to once again promote the trades in high school because not everyone is meant for college. Most students don’t know such a career exists. And tell girls, too. One HR manager says her most productive machinist is a woman.

Dean Kamen, a prolific inventor, observed that we get what we celebrate. This nation celebrates sports and entertainment figures, so there is great interest those careers. The irony is that none of them would be possible if someone had not first manufactured the equipment and TVs that bring sporting events and entertainment into our homes. Manufacturing creates wealth and it is part of the bedrock of the economy. If it goes away, kiss the “recovery” goodbye.

Paul Dvorak
pdvorak@wtwhmedia.com

It’s no secret that wind-turbine capacity, particularly for offshore turbines, continues to grow each year with 6 to 10 MW on the horizon. Even with efficiency improvements, key power generation subsystems —including generators, power-conversion electronics and transformers—are challenged to manage ever increasing heat within limited nacelle space. In addition, even if incurred power losses are as little as 3 to 5%, thermal management systems would have to dissipate 200 to 300 kW and more of heat.

While traditional air and water-cooled systems have provided low-entry costs, water cooling is becoming more challenging to implement. Installation and maintenance costs required to safely distribute enough water to adequately cool ever larger power systems are a major concern. Rising capacity and corresponding power losses are driving thermal-solution designers to consider more advanced thermal management to minimize the overall growth of the nacelle and wind-turbine infrastructure.

Limitations to air and water
Air-cooling has served small-scale wind turbines well over the years, but it’s not practical for removing the heat produced in a megawatt-scale unit. Its thermal capacity is so low that it’s difficult to blow enough air across a motor or through the converter to maintain reliable operating temperatures. That’s why water cooling is selected more often over air for larger wind turbines.

However, water systems are relatively large, and their thermal-efficiency limitations force the size and weight of power generation sub-systems to essentially track their power throughput. That is, the power density is almost constant due to the thermal performance limitations of water, making power-generation components of a 10-MW wind turbine nearly twice the size and weight of a 5-MW model. This is largely because water cooling cannot adequately remove additional heat loads without spreading them out.

Water cooling provides some reduction in size but 2-phase cooling allows a greater additional reduction.

In addition, water’s inherent electrical-conductivity potential poses the risk of a short circuit in the event of a leak, which can be catastrophic around high-power equipment. Also, because wind turbines are often in areas where temperatures routinely drop below freezing, additives such as glycol are mixed in to lower the freezing point. However, this tends to decrease the thermal performance of the coolant. Lastly, system designers must carefully select similar metals that will contact the water. Even with a deionizer or careful monitoring of inhibitor concentrations, water is corrosive. To avoid galvanic corrosion, expensive stainless steel is often selected for all plumbing and manifolds throughout the water loop to reduce the need for long-term maintenance, especially in offshore installations where remoteness and access issues require “maintenance free” operation.

Evaporative cooling
To address the challenges of cooling high-power systems in wind turbines, a few companies have developed alternatives. One in particular, uses a noncorrosive, nonconductive coolant (refrigerant) that evaporates on contact with hot electronics, in a small, light-weight, and highly efficient closed loop.

The loop has the same basic components as a water-cooling system: pump, reservoir, cold plate or cooling coils, and condenser. The big difference however is that water doesn’t change phase as it passes over the device being cooled–it simply heats up– whereas the refrigerant liquid turns to a vapor.

By taking advantage of the more efficient evaporation, two to four times the amount of heat can be removed for the same temperature difference (°C/W) than by single-phase water cooling. This directly increases power throughput, a limitation dictated by the amount of heat that can be removed from the system at the maximum reliable operating temperature.

The two-phase evaporative approach also eliminates safety and maintenance issues associated with water cooling, while allowing greater power densities. The process’ isothermal nature also reduces thermal cycling, which increases the lifespan of the turbine’s electrical components.

Sub-systems such as generators, transformers, and power-conversion electronics can be reliably driven to support up to 40% more power for the same size or weight, simply because additional thermal loads are removed without raising the subsystem temperature.For example, a 1MW power inverter is reduced in size by a factor of 3:2 when converted from air to water cooling, and then 2:1 when converted from water to evaporative-refrigerant cooling. Given the same power throughput, fewer power modules, and supporting mechanical and electrical infrastructure are required, resulting in reductions of size and weight (up to 50%), as well as overall system cost.

Size, efficiency, and benefits
The table, Cold plate performance compares a standard module cooled by air, water, and evaporative-refrigerant methods. With ambient conditions being equal and power modules limited to the same maximum surface temperature (120°C), the total measured thermal losses reached were limited to 600W for air cooling, 1,070W for the best water cooled cold plate, and 1,461W for evaporative cooling. In addition, temperature uniformity, known to impact the reliability of electronic assemblies, was much better with the evaporative-cooling system (6°C variation) than the water cooling system (19°C variation).

The evaporative system’s footprint, smaller and lighter than that of alternative thermal management equipment, coupled with its ability to reduce the size and weight of power systems, frees up valuable space in the nacelle. And, with only one-fifth the fluid flow-rate of traditional water systems, evaporative cooling presents significant performance benefits. This is because the refrigerant’s two-phase thermal-cooling capacity is significantly greater than that of single-phase water, so less fluid and space is needed. Also, two-phase precision cooling uses smaller and lighter pumps that draw less power, as well as simpler and smaller diameter hoses and manifolds that hold less coolant.

Although the comparison of cooling methods focused on power-conversion electronics that would be used in a typical wind-turbine converter, the same thermal benefits are available when comparing evaporative cooling for liquid-cooled generators and transformers. Most generator stator and transformer windings use copper-coiled water jackets to remove their heat.

Due to water systems’ lower thermal efficiency, engineers have to continually increase the size of higher-capacity generators and transformers to effectively spread out the heat. Using a pumped evaporative refrigerant unit with the same copper coils already embedded in the generator or transformer, the power throughput capacity can increase by as much as 30 to 40%, usually without a system redesign.

For small, compact equipment, Parker Hannafin’s Precision Cooling Systems developed the system in a rack-ready modular design to cool high-density power converters and inverters at capacities starting at 1.5 MW.

Almost maintenance free
Wind-turbine operators will appreciate that evaporative precision-cooling equipment requires no regular service. This is of particular importance with offshore wind farms, where accessibility for routine servicing is a major challenge and often results in costly downtime. In harsh winter conditions, entire wind farms may be inaccessible for days.

Two-phase precision cooling equipment is almost maintenance-free because:
• Pumps are more than twice as reliable as comparable water pumps.
• It is leak-proof. Should someone inadvert-ently damage the system causing a leak, the nonconductive coolant will flash to gas and not damage electronic components.
• The coolant neither freezes by nature nor requires additives or deionizers.
• The noncorrosive coolant does not react with metals.
• The only filter included in the system is a “dryer” to remove residual water or humidity from the system upon initial charge, which eliminates corrosion potential.
• It can be equipped with dry-break con-nectors for ease of module replacement, minimizing downtime during component failure replacement.

Building it in
The ease of integrating a new cooling system cannot be overemphasized. The rack-ready thermal system can be designed directly into custom cabinets or racks in nacelles, or provided in a drop-in configuration to retrofit legacy water or air cooling systems. The drop-in replacement consists of a stand-alone cooling unit, coupled with configurable plug-and-play cold-plate kits to build into various subsystems—an ideal design where a central cooling loop can support the generator, power conversion electronics, and reactor.

Rack-ready modules show how it’s possible to design high-density power converters and inverters at capacities starting at 1.5 MW. Modular inverter sections can be paralleled for high power installations. The system features electrical connectors to power bus and no-leak refrigerant connectors for an easy plug-in replacement. In addition, it scales up to 100 kW of heat rejection.

WPE

A view inside the hub, before a blade goes on, shows three pitch motors on gearboxes. Ultracapacitors are inside the three smaller enclosures. The large enclosure (center) holds controls.

On modern wind turbines, each blade is adjusted by an independent electro-mechanical pitch-control unit. The electronic controller checks the turbine’s power output several times each second. Should the power output become too high, the controller signals the blade-pitch mechanisms to turn the rotor blades slightly out of the wind. Conversely, when wind velocity decreases, the blades turn or pitch to capture more wind. Such adjustments optimize energy-generation efficiency and avoid stress or damage to the drivetrain, thereby reducing maintenance and extending turbine life.

Future designs for multi-megawatt turbines may include a cyclical pitch control, one in which the pitch adjusts during rotation to compensate for stronger winds above the hub height. For added safety, pitch controls incorporate aerodynamic braking. The rotor attains the full braking effect with a 90° “off” position for all three blades. Even if one blade-pitch unit fails, the other two rotor blades safely complete the braking process. Each autonomous pitch system is equipped with an independent backup power supply to ensure fail-safe operation of the pitchs control and braking functions in the event of a total power failure, or for maintenance.

Energy storage
Electric pitch controls use batteries or ultracapacitors for backup power. Batteries must be sized to satisfy peak-power demands and adjust the rotor blades or activate braking, even when demands occur only for a few seconds. Other battery characteristics pose design challenges for pitch-system engineers. Poor performance at extreme temperatures and a relatively short operational life can lead to periodic replacement throughout turbine life. In contrast, ultracapacitors perform reliably over a wide temperature range (-40 to +65°C), and their long operating life reduces or eliminates need for replacement over the typical life of a wind turbine.

Integrated ultracapacitor power packs
A growing number of wind-turbine manufacturers and leading integrators of pitch-control systems have designed ultracapacitors into pitch drives to take advantage of their all-temperature reliability and long operational life. Pitch controls and drives are located in the rotating rotor hub of the wind turbine or in the blade itself. The power supply and control signals for pitch drives are transferred by a slip ring from the non-rotating part of the nacelle. The slip ring is connected to a unit that includes clamps for distributing power and control signals for the three individual blade-drive units. Each unit consists of a switched-mode power supply, field bus, motor converter, emergency system, and ultracapacitor bank. Switching on the power supply charges the ultracapacitor module to its nominal voltage. Typical charging time is about one minute. The capacitor module has sufficient energy to run the system for more than 30 seconds at nominal power. The ultracapacitor module directly connects to the dc link of the motor inverter, which then drives a 3-phase, 4-pole asynchronous motor mounted directly to the gearbox of the blade drive. The motor delivers its maximum torque at low rpm. Each blade has sensors that control the blade position.

The product line of ultracapacitors from Maxwell Technologies consists of several purpose built modules.

Manufacturers continue designing larger wind turbines. Megawatt-class versions dominate much of the world market, pushing the average installed capacity per turbine near the 2-MW mark. The largest turbines produce up to 7 MW with rotor diameters up to 126 m. Ten-MW units are on the drawing boards. Larger emergency power packs are required to ensure proper blade-pitch functions for such large installations. Ultracapacitor modules rated for 75V are well suited to fulfill the requirements of megawatt-class turbines. To obtain the standard nominal voltage of 300 Vdc used for such wind turbines, four of the sub-modules are connected in series.

This is one way a bank of ultracapcitors could be wired into a DC Link.

Working offshore
Ultracapacitors’ high reliability in extreme temperatures, long operating lifetime and minimal maintenance requirements make them particularly attractive for offshore and remote wind-power applications, with difficult and costly maintenance visits. Unlike batteries, which require ongoing evaluation of their state of health (SOH) and state of charge (SOC), ultracapacitors do not need costly test runs and expensive management systems. Hence, inspection cycles can extend to several months. What’s more, specialized heating systems for cold-climate versions are not required.

Although wind energy contributes about 2% of the total world electricity supply, it is estimated that by 2020 wind’s contribution will grow to over 4%. So within a decade, another 230 GW of new capacity could be installed, which represents a market potentially worth $250 billion. Ultracapacitors have already been installed in nearly 20,000 wind turbines and will play a major role in this expansion. Current trends suggest that ultracapacitors will be instrumental in supporting industry growth by providing a simple, cost-effective, long-life solution for reliable, low-maintenance functioning of pitch control and braking systems.

The 16-V small-cell module powers wind turbine pitch controls.

Looking ahead
A bank of ultracapacitors can also provide static VAR compensation, dc-link backup, and startup power, or any combination thereof for wind turbines and wind farms. For example:

Static VAR Compensators (STATCOM) in wind-energy systems synchronize the current and voltage (i.e. unit power factor) from a generator by supplying reactive power to the system. With excellent cycling and power capability, ultracapacitors are ideal for energy storage that improves the power-quality output of individual turbines or full wind farms. As wind conditions vary, the power output and resulting voltage levels can vary by up to 10% of average output power. Ultracapacitors absorb energy to keep voltage spikes down and release energy to prevent dropouts and so smooths power delivery to the grid. As most events range from milliseconds up to a minute, ultracapacitors provide a cost-effective, maintenance-free solution for power quality issues. STATCOMs have traditionally used other types of capacitors, but the longer life and high capacitance of ultracapacitors provide a better solution.

DC-link backups provide voltage stabilization for wind turbine outputs (power quality) and ensure the wind turbine stays electrically connected to the grid. Grid disconnection can occur from disturbances on the grid side, but more commonly interruptions are on the turbine side due to low winds or from power used by the turbine dragging down the voltage (e.g. pitch motors activating). An ultracapacitor system can provide “low-voltage ridethrough” by maintaining the constant voltage required by the inverter to bring uninterrupted power to the grid. As an added benefit, the same ultracapacitor system can also provide general backup power for the dc-dc link.

Startup Power, a new concept, makes a wind turbine rated for a higher wind conditions usable in lower winds. For example, a Class 3 wind turbine could be usable in Class 4 winds by using a small motor and bank of ultracapacitors to start a lower-wind rated turbine and begin producing in lower winds. This would overcome the main issue of the power required to get the wind turbine started.

WPE

To boost energy yield, rotor blades are becoming larger and heavier. The longest production blades can span about 61-m and weigh 15 metric tons. Future designs call for lengths of 80 to 100 m and beyond. They are primarily polymer composite structures (e.g. glass-reinforced plastic) expected to last at least 20 years in a challenging service environment. When rotor blade tips slice through the air at speeds up to 300 km per hour, it’s not hard to imagine the extreme stresses they must withstand.

The trend toward larger, stronger, heavier blades is expected to continue because such designs will deliver more energy. In addition, the area available to capture wind is greater, making the turbine more efficient at lower wind speeds.

But as blade length increases, stresses on the blade are magnified. Larger blades experience more deflection across the length of the blade, increasing the dynamic load and stress on the adhesive bond line. Adhesives that offer superior long-term dynamic fatigue strength will provide better performance over the blade’s life and lower the risk of damage that requires repair or replacement.

Along with the need to improve performance, wind-turbine manufacturers must also lower their total production cost. Wind-equipment manufacturers work diligently to shorten production cycles and lower overall time and turbine production costs. Also, manufacturers are evaluating options to make reductions in lengthy production cycle times. Shorter cycle times translate into capital, labor, utility, and overhead savings, while also allowing greater flexibility in meeting unplanned demands.

Henkel Macroplast UK 1340, represented in blue, bonds the spar in place and the leading and trailing edges of the blade assembly.

Traditional blade assembly
There are two fundamentally different approaches to rotor-blade construction. Non-self supporting structures involve a box spar with an aerodynamic profile. Self-supporting structures consist of two blade halves with bonded spars that transmit all forces. The structural bonding of self-supporting blades requires adhesives with exceptional mechanical properties.

Regardless of size or construction, the quality of a rotor blade depends upon the reliability of its adhesive bonds. Glass-reinforced plastic rotor blades are fabricated in a simple sandwich design. Two blade halves are created in a composite mold. After demolding, the two halves are mated and bonded together to form the rotor blade.

The bonded blade construction is exposed to long-term direct loading. If the bond fails under stress, the blade may be damaged or even ruptured. For this reason, Germanischer Lloyd (GL) approval for blade bonding adhesives is only awarded after an adhesive passes numerous physical parameter checks.

A technician applies Macroplast UK 1340, a polyurethane adhesive that speeds rotor blade production and reduces costs by 15 to 30%. Offering breakthrough Tg better than typical polyurethanes, it is the only adhesive in its class to satisfy GL’s requirements.

Until recently, self-supporting structures such as rotor blades have been typically bonded with GL-certified two-component reactive epoxy resins. Widely accepted in the aerospace industry for structural bonding applications, epoxies offer excellent adhesion, tensile strength, and chemical and heat resistance. Limitations include extended cure times, high exotherm, and higher process costs.

Two-part epoxy adhesives are thermoset materials that cure using heat, or heat with pressure. Used for high-load assemblies and in severe service conditions, cured thermoset adhesives may soften when heated, but do not melt or flow.

Epoxies begin curing once the two parts are mixed, but require substantial time to cure completely. The total cure involves several heat-cure cycles and can last in excess of 24 hours. Longer cycle times limit a manufacturer’s throughput and result in elevated work-in-progress inventories, decreased mold use, and increased energy costs associated with cure ovens.

Epoxies also generate extreme heat, greater than 120 to 150ºC, when curing. This naturally-occurring heat can cause the bond line to swell during cure, and then shrink as it cools, which leads to stress building in the blade assembly. This stress can translate into a concentration that causes cracks under dynamic loading. Furthermore, epoxies can be inherently brittle, which limits the blades’ resistance to crack propagation. Also, epoxies can become more brittle over time, so the likelihood of cracking, especially under dynamic loads, may increase.

These limitations increase the risk for warranty claims, loss of production, and finally increased maintenance cost and blade failure. With the new manufacturing requirements for larger blades, epoxyies are reaching their limits for bonding blades.

An advanced polyurethane
A recent polyurethane (PUR) adhesive satisfies specific mechanical requirements for use in the wind industry while improving the long-term reliability of rotor blades and making rotor-blade production faster and less expensive. The material, Macroplast UK 1340 from Henkel Corp., contributes to the assembly of highly efficient wind turbines.

Because of a large spectrum of possible polymer architectures, polyurethane adhesives have been employed as a bonding agent in many different industrial sectors for more than 30 years. Construction, automotive, transportation, and shipping vessels have all benefited from the use of polyurethanes.

The recent polyurethane adhesive provides superior dynamic fatigue strength and increased resistance to crack propagation, while making the production of rotor blades more efficient than with epoxy technology. For instance, the PUR adhesive requires fewer curing steps than epoxies, resulting in reduced production costs and production cycles that are 15 to 30% shorter.

In addition to blade bonding, the two-component polyurethane adhesive is also used in other structural bonding applications on turbines including bonding components to the rotor blade, performing field repairs of blades, and securing various components inside the tower assembly.

GL’s requirements for the adhesive primarily relate to its tensile shear strength, long-term durability, creep behavior, and glass transition. The adhesive’s physical properties are temperature-dependent. Within a temperature range known as glass transition (Tg), the change in the adhesive’s mechanical properties is considerable. The glass-transition temperature separates the lower, brittle, or glass range from the upper, flexible, or rubbery-elastic range.

Extensive tests demonstrate a tensile shear strength for Macroplast UK 1340 exceeding 20 MPa in the -40 to +80°C temperature range and a Tg of 65°C and higher.

For turbine rotor blades, a Tg of at least 65°C is required to prevent bond creep or relative movement of the substrates, and achieve a certain degree of rigidity at higher ambient temperatures. However, for typical polyurethane adhesives this is usually within the range of only -30 to 45°C, depending on the required elasticity.

Tests have demonstrated a tensile shear strength exceeding 20 MPa in the -40 to +80°C temperature range for the material and a Tg of 65°C and higher. This improved tensile fatigue strength lets wind blades handle the deflection across the length of the blade and the dynamic load and stress on the adhesive bond line better than epoxies, thereby reducing the risk of damage that may require repair or replacement.The two-component polyurethane adhesive consists of a resin and a hardener. After mixing, pot life ranges from 60 to 80 minutes at the optimal ambient temperature of 20°C. The reaction speed of polyurethane-based adhesives can be altered, for considerably decreased time spent to produce rotor blades.

The adhesive’s pot life can adapt as required for a specific manufacturer’s production without the disadvantage of partially overheating the adhesive joint. Manufacturers can maximize throughput without the risk of elevated stress in the part or the potential cracking associated with high exotherm.

The recent PUR adhesive cures at a much lower reaction temperature of up to 75°C maximum when compared to epoxies that cure at 120 to150ºC. Reducing the exothermic reaction benefits the process in two ways. First, when bonding composite materials, stress cracking caused by excessive thermal loading may weaken the rotor blade. This risk is significantly reduced when the reaction temperature is lower.

Second, polymerization that takes place at high temperatures is always accompanied by changes in volume. Low-heat emission and lower thermal loading during chemical crosslinking reduces heat-related shrinkage of the adhesive. Shrinkage in the bond line can increase internal stresses, hence, a controlled shrinkage results in a more durable bond over time. The heat generated from an exothermic reaction will vary depending on the quantity of adhesive undergoing cure. In areas where larger amounts of adhesive are applied, temperatures get much hotter than in areas with less adhesive volume.

On a single rotor blade, there are considerable differences in the quantity of adhesive applied and, therefore, considerable differences in stress. At interfaces between such stress fields, mechanical flaws will occur unless the stress is relieved through elaborate tempering. This is where polyurethane systems with low-temperature exothermic reactions have big advantages, particularly when applied in thick films.

Adhesives that address the higher dynamic load and stress associated with larger blades will provide better performance over the life of the blade and lower the risk of damage that may require repair or replacement.

Adhesives that cure at room temperature and those which cure rapidly at elevated temperatures can shorten production cycles, and reduce the overall time and cost of turbine production. Room temperature curing adhesives eliminate the need for ovens, while faster curing adhesives improve throughput during the blade bonding assembly process.

Compared to conventional epoxy resin systems, the latest polyurethane delivers a number of improvements for wind-turbine manufacturers. The adhesive’s shorter cycle times boost productivity while reducing energy costs. It provides superior tensile and fatigue strength, and resists crack propagation, meeting high standards of reliability and quality.

WPE

OEMs, such as Suzlon, have a contracts department to handle their many details. “You want to form relationships with carriers,” says the company’s Logistics Director Gary Kowaleski. One route to a good relationship is with a contract that leaves little to no interpretation. He suggests at least these items for a shipping contract:

• Description and quantity of components.
• Dimensions and weights for each component.
• Define the driver’s free time.
• Scheduling: What will be delivered, to where, and when.
• Detention rate by component. Detention applies when meeting on-time criteria and when it takes excess time (longer than x hours) to load or unload a trailer. For instance, a nacelle trailer will command a higher rate of detention because it costs more to operate than, say, a blade trailer.
• Billing: How do you bill? On a weekly or monthly basis, or batch billing?
• Payment and payment terms
• Lien waiver form. It states that if payment is made, the carrier can not apply a lien against the goods. Basically, the carrier holds title to the cargo until it is released.
• Cargo value
• Cargo security
• Arbitration. When two specialized companies have a dispute, they do not want a judge unfamiliar with the industry to provide a ruling. Also, a costly civil and statutory proceeding takes time. Therefore, an independent arbitrator is hired to hear both sides and make a ruling.
• Road surveys: Identify the route, low bridges, high-voltage wires, and other hazards
• Provide a full time on site coordinator and define their role in detail.
• Damage claims: Equipment is occasionally damaged in transport so discuss the process ahead of time so the transport company knows what it will be held accountable for.