Why is Hose Fittings for Mining Machinery Better?

Modern mining equipment, whether surface or underground, presents challenges to hose manufacturers to provide products that meet or exceed equipment&#;s criteria. New equipment designs require higher working pressures, larger inside diameters and compounds to handle multiple fluids. Systems that operate at higher pressures provide quicker performance, which can enhance production output at the mine site while demanding more out of hoses. 

HT-HYDRAULICS supply professional and honest service.

Hose offerings today are designed to serve multiple areas of operations with higher pressure ratings, better bend radiuses and abrasion-resistant covers to accomplish the most severe requirements. Mine owners are challenged daily with keeping equipment in good working order at all times; downtime is not an option. The process requires many contiguous operations going on at the same time; when one area is down, it may greatly affect other areas of the operation. 

Hose is an integral part of most equipment in mines, and by design, the weak link in the system. This makes it imperative to have the best quality hose and accessories that are available on a moment&#;s notice to keep mines up and running. This article discusses two types of mining, surface and underground, and compares the two for hose needs.

Surface mining

Surface mining equipment requires much larger hose and fittings coverage than in underground mines. Diverse types of equipment &#; including scrappers, dozers, haul trucks, water trucks, hydraulic shovels and drill rigs &#; all have similar hydraulic needs. Typically seen are ¼-inch to 2-inch hydraulic hoses in braided and spiral constructions that cover low, medium, high and ultra-high pressure ranges. 

It is important to train machine operators on the differences between each of the hoses to avoid premature failure. For example, if an operator replaced a spiral hose with a braided product it could have catastrophic results. The maintenance team must be educated on the differences between the two constructions. All too often, this incorrect substitution will occur and the next maintenance person will replace it with the same hose that failed.

The low-pressure side of the machines typically use ¾-inch to 4-inch hydraulic suction return lines and are less vulnerable to failure. Engine fleet type hoses are common for brakes, fuels, oils and high-temperature transmission lines and use reusable couplings for ends attachment, which are convenient for field replacement. These types of hoses are generally built more to an automotive standard; therefore, hose suppliers must be well-versed in finding replacements for the mine owner. Some manufacturers produce engine hoses with standard inside diameters to eliminate the need for reusable couplings; therefore, existing crimp-type couplings can be used to cover many hose styles and reduce inventories. 

Hose coupling thread ends will require American standards including SAE, JIC, NPT, Boss O-Ring, Flat Face, Code 61 and Code 62 flanges. Metric ends including DIN, BST, BSPP, Komatsu and JIS may also be required. Many mine sites do hydraulic hose crimping on-site using in-house inventories and crimpers to eliminate any hose-related downtime. Many mine sites also utilize premade hoses that hang on the wall for many high-pressure or specialized lines for a specific piece of equipment. Theses hoses may require 5,000 or 6,000 psi, and liability is passed to the equipment manufacturer on assembly fabrication. In other cases, premade hoses can also be tied to warranty issues for new equipment.

Hydraulic hoses have been developed around total system pressures and constant hose product lines are common today. Using a constant hose system pressure product line either in braided or spiral construction eliminates large inventory needs, reduces purchases, reduces mix-and-match hoses and provides complete coverage to simplify hose selections. This again makes it imperative to have a well-trained customer to avoid improper hose selection. 

Another important issue to consider is hose abrasion. It is noted that 95 percent of hose failures occur from outside of the hose through abrasion by rubbing on the equipment or other hoses. Different methods using various hose cover protections are used including steel spring guarding, flat spring guarding, flat spiral plastic guarding and abrasion sleeves. These all have a common purpose: hose abrasion protection. Most manufacturers today have special blended hose covers that have medium-to-high abrasion built into the covers without affecting the bend radius. Each mine site&#;s culture dictates what is used, e.g. abrasion sleeves on the hose or extra-tough covers.

Most hoses used at a surface operation are hydraulic in nature. But many industrial hoses are also used in shops and at the mining sites for air, water, nitrogen charging, drilling air, petroleum and water. Most mines utilize large water pumps to remove surface water from the mining site; these hoses can range in size from 3  to 12 inches in diameter and are capable of transferring water several miles. Most coupling connections are common industrial standards. 

Underground mining

Slightly more than 50 percent of mining is conducted underground. Over the last several years, underground mining has become an efficient, sophisticated operation utilizing the latest technology. New processes use less manpower since the machines now do most of the work. The hose needs are slightly different in this operation and are split into several different areas of operation. The equipment used in these processes is all hydraulically operated and requires dependable hose.

• Continuous miners: This process readies the mine for the equipment used to mine and makes "rooms" for the longwall mining process. Typically, hoses rated to between 3,000 to 5,000 psi are used in this process.
• Bolters and drills: Equipment used to predrill holes for blasting and to secure roof bolts; 3,000 to 5,000 psi.
• Longwall system: Roof support shields, shear and monorail for ore production. This is the science behind economical and safe mining. It is operated with a series of hydraulic cylinders pushing on shields to hold up the roof of the mine. This requires several hoses ranging from 5,000 to 6,000 psi.
• Monorail: System to provide water, hydraulic pressure, return hoses and electrical and cabling to the long wall; 500 to 5,000 psi.

Hydraulic hose

It is important that Mine Safety and Health Association (MSHA)-approved hoses are used in the mining process. Hydraulic hoses and couplings meet or exceed MSHA requirements. Because mining can be a very abrasive process, an additional abrasion sleeve may be required on vulnerable parts of the hose assemblies that come in to contact with equipment structure or other hose assemblies. Manufacturers have developed hose cover compounds that can withstand severe abrasion to eliminate the cost of the sleeves.

The coupling ends that are utilized are JIC, NPT, O-Ring Boss and Flat Face and are commonly available. DIN, BST and BSPP metric ends are used on some systems. Also, a common coupling used in the process is a Staple-Lok or Stecko fitting to securely attach hose to machinery and other hoses. The fitting construction utilizes pins or staples into a locking collar to prevent disconnecting while in use. Typically, ¼-inch to 1-inch hoses use the single-staple system, while  1 ¼-inch to 2-inch hoses use a double-staple system for securing the coupling. Both styles are rated to 5,000 to 6,000 psi and are critical for quick changeout of damaged hose runs. Some mines like to have on-site capabilities to make assemblies along with off-the-shelf, premade assemblies for critical spares. Again, it is imperative to properly train anyone that assembles hose assemblies on-site.

Industrial hose

Several types of industrial hose are used in the mining process at every stage. Some of the most common are:

• Yellow mine spray hose: Used for firefighting and dust control; supplied in ½-inch to 3-inch sizes with working pressures to 1,000 psi.
• Rubber and PVC rock dust hose: Used for dusting of walls for illumination process.
• Split PVC cable guarding: Used as a cable protector; supplied in 1 ½ inches to 3 inches.
• Mine conduit-rubber tubing: Also used as a cable protector; supplied in 3/8-inch to 3 inches.

Several other types of hose are used as well from general service air and water hose to pressure-washing hose to ducting hose for dust and ventilation. An array of industrial hose couplings are used in this process from cam-and-groove to hammer locks to firehose connections ranging in sizes from ¼-inch to 12 inches in diameter.

Conclusion

Hose has been part of the mining process for more than 100 years and has evolved to keep up with the demands of this rigorous industry with products that continue to provide safety for mine workers while getting the job done. Hose continues to play a huge part in mining of raw materials around the world today.  

Are you interested in learning more about Hose Fittings for Mining Machinery? Contact us today to secure an expert consultation!

The mining industry, known for its harsh and unforgiving environments, demands reliable, high-quality equipment to ensure safety and efficiency. Longwall mining, which accounts for around 50% of total underground production, has had the largest continual impact upon underground coal operations in the U.S. over the last two decades.

Longwall mining is an underground mining operation in which a large panel or block of coal spanning up to 1,500 ft across distances of two to three miles is extracted. Longwall mines are characterized by low ceilings and tight spaces in which workers must operate heavy machinery. Hydraulic-powered roof supports, also called shields, protect the working area of the mine by extending as a shearer cuts back and forth along the coal face. Once it is cut by the shearer, coal falls onto a large chain conveyor for transport to the mine. The movable hydraulic shields in longwall mines advance with the shearer throughout the mining process, enabling increased productivity as well as improved safety for miners.

Safety is imperative in the mining industry, particularly when it comes to the dangers of roof falls and lack of clean air in underground coal mines. It is vital for the equipment used in mining to be thoroughly tested to meet internationally approved MSHA standards and provide consistently reliable performance to ensure safety of operations and individuals in extreme environments.

High Performance for Mining

Because of the rigid safety and performance requirements for mining equipment, Parker Hannifin and other major hose manufacturers offer products designed specifically for mining applications. Parker&#;s GlobalCore 187 hose is a 1,000 psi (7 MPa) constant-working-pressure hose specifically engineered for the mining industry. ISO requires impulse testing at 133% maximum working pressure and 100°C for 200,000 cycles for standard and compact type hoses. GlobalCore 187 hose exceeds these requirements and can be used as a high-pressure return line or where other hoses may be overkill or requires a lower bending force.

Parker&#;s GlobalCore 187 hose meets or exceeds ISO requirements and is the only 1,000-psi constant-working-pressure hydraulic hose offered in sizes &#;8 through &#;48 (½- through 3-in. ID).

Constant-working-pressure hoses contradict traditional hydraulic hoses, in which pressure rating decreases as the inside diameter increases. For instance, if the maximum pressure requirement 1,000 psi, you could specify one hose family operating with a constant working pressure of 1,000 psi across all diameters for your hydraulic system. Converting from various product lines to a singular hose family that provides constant working pressure across sizes means a simplified selection process as well as reduced inventories, maintenance costs, and downtime. 

The unified GlobalCore series of ISO hoses as the first family of 1,000 psi-rated constant-working-pressure hydraulic hose sizes from &#;8 through &#;48 (½- though 3-in. ID), and with half the minimum bend radius specified by SAE and ISO . This feature reduces overall hose assembly length, promotes easier routing in the restrictive areas of underground mines, and decreases the number of bent tube fittings necessary. The tighter bend radius capability also means longer hose life in applications where machinery movement causes sharp bending of hoses.

Wide Selection for Safety

Although today&#;s hydraulic hose performs better than ever, a lack of maintenance, equipment abuse, or unforeseen circumstances can lead to failure of any hydraulic hose. The risk of serious injury resulting from the uncontrolled release of high pressure hydraulic fluids is an ongoing concern. Hydraulic fluid injection injuries are caused by a release of pressurized hydraulic fluid penetrating the skin. A pinhole-sized leak can travel at the same velocity as a bullet&#;600 ft/sec. According to research, more than 10% of mine safety incidents in the United States involve fluid power systems, with 1% of those resulting in serious injury or death.

When connections have been properly prepared and crimped, a hose should not come loose from its end fitting. Additional safety can be provided by specifying a hose whip restraint, which limits movement if a hose should be pulled away from its end fitting.

In addition to the 187 hose, Parker has an entire range of MSHA approved hoses, fittings, and equipment to service the needs of the mining industry. With a thicker, more durable outer cover to prevent impact damage from debris, Coalmaster hoses are intended for tough underground conditions. Paired with the SteckO fitting system, Parker&#;s Coalmaster products provide increased performance and reliability in highly abrasive environments.

Boosting Profit by Reducing Downtime

Longwall mining has shown a significant increase in production and today accounts for the largest amount of tonnage mined among underground methods. Because of this shift, improved crimping equipment that can withstand the harsh environment and keep up with increased production is essential. However, it must be cost-efficient.

Several manufacturers offer hydraulic hose crimping equipment that makes factory-quality hose assemblies quickly, easily, and cost-effectively. Parker's Parkrimp family of crimping machines crimp fittings to the proper diameter every time. These crimpers are simple to operate and built to provide years of dependable service. Parker&#;s family of Parkrimp models can crimp straight or bent-stem fittings from ¼- to 2-in. diameter and cover needs ranging from high-volume productivity to portable, on-site assembly. 

In order for crews to efficiently operate in the cramped conditions of underground mines, equipment must be easy to use, install, and change out. Adding a global asset tagging and identification system to your mining operations would provide a fast, accurate and convenient hose assembly replacement regardless of where or when the original assembly was made. Adding an asset tag, such as Parker&#;s PTS label, can save users at least 15 minutes of downtime (simply stated as the time spent waiting in a store, or as the additional time spent in first removing an assembly before proceeding with the repair).

If the average cost of labor and machine downtime is calculated at the low end of $60 per hour, PTS can save the user $15 in direct productivity losses. For users with multiple, untimely failures per month, this can add up to considerable savings. Many users have documented downtime of two to three hours or more due to hydraulic hose failure, and at labor and loss productivity rates of up to $500 per hour or more. In such circumstances, asset tags can be invaluable in helping to ensure maximum machine or vehicle uptime.

Kyri McDonough is marketing services manager at Parker Hannifin&#;s Hose Products Div., Wickliffe, Ohio. For more information, click here www.parker.com/hpd. This article is based on material appearing in Parker&#;s Motion & Technology Blogs.

The company is the world’s best Hydraulic Hose Fitting for Metallurgical and Petroleum Equipment supplier. We are your one-stop shop for all needs. Our staff are highly-specialized and will help you find the product you need.