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IntroductionSpringsele® and Teesele® are two seal ranges developed by James Walker to solve problems commonly experienced by manufacturers and users of oilfield equipment.
Supply commitments
Our standard ranges of both these seals fit housings to SAE AS568A and BS ISO 3601-1 Class A. Non-standard sizes are manufactured to order. We therefore make the following commitments to our customers. We will:
Both Springsele® and Teesele® are double-acting and will effectively seal applications that are subjected to:
Springsele® is recommended for static duties, whereas Teesele® is capable of operating in a dynamic mode. Both seals can operate at high pressures with large extrusion gaps.
Preferred design
Springsele® is the preferred design for the majority of oil and gas applications (except where the duty is dynamic and Teesele® should be used). This is due to the ease of assembly of Springsele® and its ability to work efficiently with large clearances.
Close-up view of Springsele®.
In addition, Springsele® is rapidly gaining acceptance as the standard for sealing casing seal receptacles in surface wellheads, where it is often used in conjunction with the James Walker FS Casing & Tubing Seal. 
Close-up view of Teesele®.
Please note that the use of Springsele® in applications where relative motion is experienced can result in wear or damage due to metal-to-metal contact between the spring and housing.
Typical applications
These two seals are used for many oil and gas duties, including:
Both Springsele® and Teesele® can be:
Materials
The standard elastomers used for both Springsele® and Teesele® are:
In addition, Elast-O-Lion® 985 and FR25/90 are used for low-temperature duties, but tooling charges usually apply. Other custom materials are available.
Elast-O-Lion® 101 - Hydrogenated nitrile HNBR. This elastomer provides high mechanical strength and wear-resistant properties. It has good resistance to many oilfield chemicals including H2S and amine corrosion inhibitors. This grade is quailified to the stringent Norsok M-710 standard that covers both rapid gas decompression (RGD) resistance and sour gas (H2S) ageing tests. It is also approved to many other RGD specifications.
FR58/90 - Fluoroelastomer FKM, based on Viton® B from DuPont Performance Elastomers. This elastomer has excellent chemical and thermal properties, and is quailified to the stringent Norsok M-710 standard that covers both rapid gas decompression (RGD) resistance and sour gas (H2S) ageing tests. It is approved and specified by many oil producers and equipment manufacturers.
Elast-O-Lion® 985 - Hydrogenated nitrile HNBR/HSN. This grade offers improved low-temperature capability although with reduced mechanical properties and RGD resistance compared to Elast-O-Lion® 101.
FR25/90 - Fluoroelastomer FKM. This material combines an improved low temperature capability with excellent thermal and chemical properties. It is quailified to the stringent Norsok M-710 standard that covers both rapid gas decompression (RGD) resistance and sour gas (H2S) ageing tests.
Springsele® anti-extrusion springs - Toroidal-wound springs of corrosion resistant material. Options are stainless steel to BS EN 10270-3-1.4401 (formerly Grade 316 S42) or nickel-based Alloy 600 - UNS N06600.
Teesele® anti-extrusion elements: Precision machined in virgin polyether-etherketone (PEEK® 450G from Victrex plc). This rigid thermoplastic engineering polymer is highly resistant to chemical attack and wear at high temperatures. Other materials are also available including various filled grades of PTFE.
Operation
Elastomeric materials have a very high bulk modulus and are virtually incompressible. Therefore, when a Springsele® or Teesele® is installed, the elastomeric element is deformed slightly in its housing to give a predetermined level of radial seal compression.
The resulting force provides positive fluid sealing at zero system pressure. When system pressure is applied, the elastomeric component deforms further but, because of the initial squeeze, the sealing force always exceeds the force exerted on the seal by the fluid.
This deformation moves the Springsele® anti-extrusion spring into the clearance gap of the housing's low pressure side. With Teesele®, the anti-extrusion ring is activated by system pressure. These actions effectively prevent extrusion, even at high system pressure.
Operating capabilities
The materials of construction of Springsele® and Teesele® dictate the seals' temperature capability in air, as follows:
Elast-O-Lion® 101
Minimum operating temperature: -29°C (-20°F).
Maximum operating temperature: +160°C (+320°F) with short excursions to +180°C (+356°F).
FR58/90
Minimum operating temperature: -27°C (-17°F).
Maximum operating temperature: +210°C (+410°F).
Elast-O-Lion® 985
Minimum operating temperature: -55°C (-67°F).
Maximum operating temperature: +160°C (+320°F).
FR25/90
Minimum operating temperature: -41°C (-42°F).
Maximum operating temperature: +200°C (+392°F).
Product validation
Both Springsele® and Teesele® have been validated statically in high temperature oil at: 155MPa (22,500psi) and +140°C (+285°F).
Springseles of Elast-O-Lion® 101 have also been validated by customers under under full API6A PR2 procedures. The most extreme validation was at: 69MPa (10,000psi) from -29°C (-20°F) to +177°C (+350°F).
Groove fill
Both seals are designed to operate with higher levels of groove fill than conventional 'O' rings and 'O'ring/back-up systems. It has been proven that high groove fill can enhance RGD resistance.
Seal stretch
Springsele® is designed to be stretch-fitted into a groove for external applications, and compression-fitted into a groove for internal applications. In certain circumstances, seals can be retrofitted into non-standard housings, but advice should be sought from our Technical Support Team.
Teesele® uses rigid plastic back-up rings, and a standard seal cannot be retrofitted into a non-standard housing.
Non-standard seals in both formats can be made to order.
Seal squeeze (radial compression)
Both products are designed with a higher level of squeeze than conventional 'O' rings. This helps to improve the low temperature sealing performance and RGD resistance, and caters for housing offset in duties with large extrusion clearances.
Installation
Both seal types are easy to install, even in a blind recess. The use of integral anti-extrusion springs in Springsele® eliminates the risk of these elements becoming dislodged or damaged during assembly. The anti-extrusion elements of Teesele® are bi-directional to prevent incorrect installation.
With both seals, particularly when subjected to stab-in, the metal components require a 15 to 30 degree lead-in chamfers.
Seal sizes and configurations
Springsele® and Teesele® are available in many sizes and configurations. Our standard ranges fit housings to SAE AS568A and BS ISO 3601-1 Class A.
Within the charts of our Sealing Products & Materials for the Oil & Gas Industry guide (see below for pdf download) are a number of seal configurations according to the axial dimensions of the housing and the mode of operation:
How supplied
There are thousands of potential variants within a single standard such as SAE AS568A or BS ISO 3601-1 Class A. To simplify stockholding and meet the vast majority of customers' applications, we have invested significantly in fast manufacturing techniques to offer customers compressed lead times for these vital ranges of products.
Preferred configuration:
External Springsele® for long housings in Elast-O-Lion® 101, with stainless steel anti-extrusion springs.
We will:
Click here to download the Elastomeric seals & components for the Oil & Gas industry guide pdf
Click here to view James Walker products in a wellhead
