Welcome back for another round of HCWHB! We hope you had a great Thanksgiving Holiday!
November’s focus will be on the advantages of using twin wire arc spray.
I am going to touch on the technical, economical, and operational advantages in using a twin arc spray system. Enjoy my tips below:
To view previous articles, click here.
To view Polymet’s thermal spray product catalog, click here.
Welcome back for another round of Hard Coatings with Hard Bob! In this article we are focusing on the effect of atomizing air pressure on arc spray coatings.
When arc spraying, there are a number of technical parameters that will affect the coating. One of the most important parameters for arc spraying is atomizing air pressure. Changing the air pressure has a major effect on the following: density, hardness, oxide content, surface roughness, machinability, and bond strength.
If you increase the air pressure, the particle velocity increases and the particles become smaller because they are atomized more finely. I recommend that the desired coating properties first be determined before selecting an atomizing air pressure. Check out the rest of this month’s tips in the article below:
To view previous articles, click here.
To view Polymet’s thermal spray product catalog, click here.
Last week at FABTECH Las Vegas, Bob Unger, Sales Manager at Polymet, gave a presentation on “New Developments in Cored Wires for Thermal Spraying.” The presentation focused on the use of unique alloys in thermal spraying that are not available in solid wire form. These unique alloys include amorphous, nano, and self-fluxing alloys. Bob also discussed successful applications for these cored wire alloys.
Bob’s presentation was a part of FABTECH’s Conferences and Professional Events segment of the show, which included various presentations, seminars, and networking opportunities. His particular talk was held in the thermal spray conference room. Other thermal spray industry presentations included “Corrosion and Protection Offered by a Dispersed Oxide Coating System” and “Thermal Spray Methods & Equipment – 1800’s through the 1930’s.”
Thanks for valuable insight on cored wires Bob!
Polymet Corporation, a leading manufacturer of hardfacing wire, welding, and thermal spray wire, will exhibit at the 19th International Oil & Gas Industry Exhibition & Conference in Singapore, November 27-30, 2012. OSEA is Asia’s most important business technology event for the Oil and Gas industry. The event gathers key companies from around the globe in an extensive showcase of products, solutions, and technologies in this industry.
Polymet is excited to attend OSEA-2012 in order to expand its global reach and promote its full line of industrial hardfacing alloys, welding, and thermal spray materials in this rapidly growing area of the world. For this particular show, Polymet will highlight their POLYSTEL products for valve hardfacing. Polymet is eager to display the extreme benefits of hardfacing with this solid, small diameter, Stellite® equivalent wire. These cobalt-based POLYSTEL wires are comparable to Stellite® 6, Stellite® 12, and Stellite® 21. They are produced in a proprietary hot extrusion process that allows Polymet to spool wire as small as .020” diameter, suitable for automatic TIG operations.
Bob Unger and Danny Newman, Sales Managers of Polymet Corporation, will be exhibiting at OSEA in Singapore, as well as visiting existing customers in the region. Bob Unger states “We look forward to OSEA 2012 as a perfect opportunity to meet with our distributors in the area as well as to develop new relationships with prospects. This area of the world is growing so quickly and the demand for our products in the welding and thermal spray industries is truly exciting.”
Stellite® is a registered trademark of Kennametal Stellite
Polymet Corporation, a wire manufacturer for hardfacing, welding, and thermal spraying, announced that it will increase its capacity for their cored wire process. The company plans on upgrading current machinery as well as purchasing an additional mill to drive production.
Cored wire, also known as flux cored wire and metal cored wire, has become a staple at Polymet alongside hot extruded solid wire products. Cored wire consists of an outer metallic sheath housing an internal powder core, suitable for both thermal spraying and MIG welding operations. Business for these cored wire products have grown tremendously for Polymet over the last several years and increasing capacity will enable production to meet the growing demand.
A major capital investment for this project will include the additional of a new mill. This will allow for significantly larger output, shorter lead times for customers, and the ability for research and development engineers to experiment more frequently. Improvements to existing machinery will also take place. The project is expected to be completed over the next 8 to 10 months.
“Our cored wire products have really taken off over the years, especially for the thermal spray industry,” says Bob Unger, Sales Manager at Polymet. “It is critical for us to deliver the attention necessary to increase our output for these products. I am very excited to be involved in the development and growth of this area at Polymet.”
Once a month Polymet’s “Hard Bob” will publish 5 helpful tips for thermal spraying in “Hard Coatings with Hard Bob.”
This is an opportunity for customers and operators to gain valuable insight and recommendations from a true industry expert, Bob Unger. Bob is the Sales Manager at Polymet and has been working in the thermal spray industry for over 30 years. With his extensive knowledge, expertise, and passion for the industry, Hard Bob’s tips will serve as your one-stop shop for all thermal spray guidance.
Each Spray Talk article will focus on a specific topic. The September issue will concentrate on Cored Wire for Arc Spraying.
Dive into our first article below!
To view previous articles, click here.
To view Polymet’s thermal spray product catalog, click here.
Polymet Corporation, a leading manufacturer of high performance hardfacing wire, welding wire and thermal spray wire, is pleased to announce that it has successfully completed ISO Certification audits. This has resulted in an upgrading of Polymet’s quality management system to the new internationally recognized benchmark of ISO 9001:2008 with AS 9100:2009 Revision C.
The ISO 9001:2008 aims at guaranteeing effectiveness within an organization. The revision’s principles focus on quality management to promote continual improvement. This is the basis for establishing efficiencies throughout an organization.
Some of the benefits of these revised standards are that they are simple to use, clear in language, readily translatable, and compatible with other management systems.
Bill Mosier, President of Polymet Corporation, commented “We believe the upgrade to ISO 9001:2008 / AS 9100:2009 Rev C is significant for future national and international business opportunities and demonstrates Polymet’s dedication to quality and service.”
A look at the characteristics and advantages that can result in overall cost savings.
Quick highlights – Metal Cored Wire:
- High deposition efficiency
- High deposition rates
- Increased duty cycles
In today’s industrial world, metal fabricators have an array of choices to select from when deciding which welding process and consumable to use for a specific application. As always, product cost, efficiency, and quality will play a key role in these decisions. It is a continuing struggle to find consumables that can reduce costs without sacrificing the integrity of the work. Many fabricators, however, are finding that metal cored wire is quite a beneficial change. While this type of consumable is not new to the welding industry, the classification and the advantages of using metal cored wire are not always recognized.
The American Welding Society classifies metal cored wires under the same specification as solid MIG wires. Metal cored wires have a very similar construction to flux cored wires but the performance and functionality parallel solid MIG wires. The basic composition of metal cored wire is a tubular electrode comprised of an outer metal sheath and a core of powdered materials. Both the outer sheath and internal powder composition can be formulated to meet specific requirements.
The outer metallic sheath can be cobalt, nickel, iron or stainless steel-based. This sheath conducts the electrical current during the welding process and the current carrying density is greater in metal cored wires, therefore increasing the deposition rate as compared to solid MIG wires. Also, improved penetration and sidewall fusion capabilities are made possible due to these increased deposition rates.
Metal cored wire internal composition consists of both elemental and alloyed powders such as nickel, cobalt, chromium, tungsten, molybdenum, and manganese to name a few. This internal composition of metallic powders is far less conductive than the outer sheath carrying the electrical current, resulting in a more controlled weld pool.
Making the change to metal cored wire can be extremely advantageous. There are a number of factors that contribute to the success of metal cored wires, including:
The deposition efficiency of a consumable is the amount of material that converts to weld metal. During the welding process, a portion of the consumable is lost to slag, spatter, and fumes. The lower this percentage of lost consumable is, the higher the deposition efficiency will be. Depending on the transfer used, metal cored wire can exhibit a deposition efficiency range of 92-98%. This high efficiency is due to a decreased volume of slag and spatter that require removal from the weld and parent material. Reduced fume levels are also reflected in the deposition and create a healthier work environment for the welder.
Higher deposition rates are also seen in the implementation of metal cored wire. The deposition rate is the amount of weld metal deposited during a given time. The deposition rate of metal cored wire is about 57% higher per hour than solid MIG wire. This ultimately results in higher achievable welding speeds.
Travel speeds rely on duty cycles. During the welding process, a duty cycle refers to the amount of continuous arc time. Factors such as travel time, equipment, slag removal, and replenishing consumables affect the duty cycle. Shielded metal arc welding using stick electrodes can only produce about 12 minutes of welding every hour, whereas metal cored wire yields a duty cycle of about 30 minutes an hour. While solid MIG and flux cored wire can achieve these high duty cycles as well, only metal cored wire can take the process to a whole new level with faster travel speeds. Metal cored wire can account for increased travel speeds of 35-40%. Fabricators can practice automatic application with high duty cycles and travel speeds without jeopardizing weld integrity and appearance.
As stated earlier, the main objectives for fabricators are to achieve productivity and efficiency at a lower cost. While metal cored wire has a higher cost per pound than other consumables, the true economic payback is seen during the process itself, not in the initial cost of materials. Labor costs are generally a substantial portion of total cost and therefore welding efficiency and productivity must be weighed heavily. When assessing the change to metal cored wire, keep in mind these key points that result in overall cost savings: high deposition efficiencies, high deposition rates, increased duty cycles and faster travel speeds.
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