Oilfield Encoders Eliminate Barriers

Gurnee, IL – Dynapar announces the introduction of the EN series of oilfield encoder suitable for use in Zone 1 hazardous locations. What makes the new incremental encoders unique is their ability to operate in hazardous areas without the need for intrinsic safety (I.S.) barriers. Removal of the I.S. barrier reduces system cost, simplifies wiring, and provides for a more permanent installation. Also, faster data acquisition rates are possible since losses through the I.S. barrier are eliminated. The new encoders feature Ex ia mb e IIC T4 ATEX certification, along with an industry-leading -50 to +100C operating temperature range.

Field-Friendly Concept

The new harsh duty incremental encoders are designed with “Field-Friendly” characteristics in mind-compact, easy to mount, easy to wire, and reliable in harsh conditions. These traits are routinely designed into NorthStar brand heavy-duty encoders, but become much more challenging when Zone 1 certification is required. The new encoders incorporate an increased safety interface to eliminate the need for external I.S. barriers, and use encapsulated electronics to prevent unwanted component contact with flammable gases. As a result, the encoder circuit isn’t limited in electrical energy the way standard I.S. encoders are, therefore allowing for longer cable runs and improved signal-to-noise ratio. The EN series also features a field wire-able terminal block inside a conduit box with common ¾” NPT entry. Optional ATEX-rated glands for armored or non-armored cable use are also available.

Rugged Design for Oilfield Motor Use

Starting with Dynapar’s proven phased-array ASIC sensing technology, the encoders feature a rugged design with wide sensing gap, mechanically captured bearings, and non-glass code discs. The result is a robust incremental encoder that can handle excessive shock and vibration that would destroy more fragile industrial encoders. In addition, the housing receives hard anodizing to resist corrosion in less-than-perfect operating conditions. The EN42 variant is configured with a stainless steel hollow shaft and dual-split clamping collar for motor mounting. The standard anti-rotation arm is a heavy duty 5/16″ threaded tether rod with swivel ball ends for reliable installation. The EN44 model mounts directly to an IEC motor flange and incorporates an innovative isolated flex coupling. This special coupling not only isolates the encoder electrically, it compensates for motor shaft run-out and end-play.

Safety Coupling Catalog

Zero-Max has published a 12-page Zero-Max catalog of Torq Tender overload safety couplings. These overload safety couplings disengage motor drives for overload protection. They protect motor and drive systems from jam ups and excessive loading.

System designers will find this new catalog helpful when examining overload protection options for a particular system design. Available in models that will disengage torques from 2 to 3,000 in. lbs., mechanically operated Torque Tenders often are the best design option because they are tamper proof and do not require costly and potentially risky calibration procedures. The torque value is controlled by the Torq Tender part number ordered and preset at the factory.

Torq Tender operation in most mechanical power transmission systems is simple. When the load exceeds the Torq Tender rating preset with precision tempered torque springs, the unit’s drive key pivots out of a slot, disengaging the Torq-Tender coupling. Once the overload is removed and the speed reduced, the Torq Tender resets itself automatically. This automatic resetting action engages the system’s drive shaft and puts the entire drive system back into motion at its original position.

Torq Tenders are available in many standard sizes. The smallest is the TT1X with a 2 to 60 in. lbs. torque rating. The largest is the TT4X with a 750 to 3000 in. lbs torque rating. Special Torque Tender designs are also detailed in the new catalog for handling various mountings, bore sizes and housings.

Inside the new brochure is complete selection and ordering information. Also, you can now size, select and see the right Torque Tender solution with Zero-Max Partstream, the configurable 3D CAD downloads.

Centa’s Quality Assurance Excels

CENTA is the first company worldwide to which Germanischer Lloyd (GL) has conferred the responsibility for alternative product certification of type-approved couplings. In the future, CENTA will have the authority to carry out acceptance testing and final stamping of those couplings that have previously been classified as approved types. These tests must be performed in accordance with the “Alternative Product Certification,” a modular certification system developed by Germanischer Lloyd (GL). The approval becomes valid by their joint signatures on the appropriate product certificate.

CENTA is one of the leading manufacturers of flexible drive components worldwide and has been supplying couplings for marine applications for more than 20 years. In 1990, the company’s quality management system was first approved by DIN ISO 9001. All subsequent audits were passed successfully, and recently the classification society Det Norske Veritas (DNV) attested that the coupling manufacturer supports a higher-than-average quality management system.

Several international classification societies, such as the Det Norske Veritas (DNV), Nippon Kaiji Kyokai (NKK), and the Maritime Register of Shipping (MRS), have granted CENTA the authority to use their approval stamp on its series couplings. CENTA has a stock of approximately 65 approved types. In 2007, roughly 2,000 certifications by several classification societies were carried out on CENTA’s premises. In the future, CENTA will be the first manufacturer worldwide to be granted approval by Germanischer Lloyd (GL) to perform acceptance tests on its own flexible couplings up to 100 Nm.

Germanischer Lloyd (GL), one of 10 internationally recognized classification societies, has developed technology and quality standards for more than 140 years–standards that ensure the safety of more than 6,500 ships all over the world. “We have maintained close cooperation with several classification societies for more than 20 years”, says Gerhard Kirschey, founder of CENTA Antriebe Kirschey GmbH. “We continually strive to improve the quality of our products and processes. Approval by Germanischer Lloyd for carrying out acceptance testing of our couplings on our own, in-house, indicates that our quality management system is on the right track”, Kirschey explains. “We are very proud of this sign of confidence and confirmation of our efforts, which are supported by our employees’ high commitment level.”