The RS Clare Range

Introduction

The R.S. Clare range of advanced Valve Lubricants for the Oil & gas Industry has been developed in conjunction with Original Equipment Manufacturers and Production, Drilling and Service operators.

R.S. Clare's valve lubricants have been well proven in the field providing the user with 'failsafe' and 'cost effective' valve lubrication.

In the exploration and production of crude oil & natural gas, severe problems can be encountered due to the presence of H2S, CO2, condensate, hydrocarbon solvents, acids and other chemicals present in the well production system.

Such chemicals and compounds can breakdown conventional lubricants, resulting in the lubricants being 'leached out' of the valve cavity. This can render the internal valve components dry, exposed to wear and damage from increased friction and corrosion and will permit the build up of contaminants in the valve cavity.

This process can cause severe valve operational probelms. Such problems include damage to the component sealing surfaces resulting in compromised sealing, an increase the required actuation torque or ultimately in seizure of the valve.

Gate Valve Lubrication

 The function of the valve lubricant is to:

Displace harmful chemicals and fluids from the valve cavity.
Provide corrosion protection to the ‘exposed’ internal valve components.
Provide a ‘secondary seal’, thus reducing the build up of contaminants in the valve cavity, such as sand, that may be deposited from the flow line.
Provide an integral lubricating film between the gate & seat, thus controlling friction and minimising component wear.
Provide lubrication to the stem thread, on a manually actuated valve.
The torque required to operate an un-lubricated valve at a specific pressure can be as high as twice the torque figure for an effectively lubricated valve.
The lubricant must have high adhesion to the internal surfaces of the valve cavity and components to withstand the high contact stresses and cavity pressures.
 
Gate Valve Lubricant products

Gate & Seat components
 The Standard Service lubricant, GP Valve Grease, is a mineral oil based lubricant with a concentration of solid lubricant. GP Valve Grease exhibits good metal adhesion and water resistance. However, field experience has demonstrated that the performance of Standard Service lubricants is limited by the aggressive production and process chemicals and also the hydrocarbon fractions within the crude itself.

In order to ensure optimum valve performance, a non-petroleum based, premium Clare gate valve lubricant should be selected.

Valve Lubricant 601 is a fully synthetic lubricant, ensuring long term lubricating and sealing qualities within a temperature range of -20°F to 450°F. 601 is specially formulated to provide optimum resistance to aggressive produced fluids and gases and process chemicals.

The adhesive texture of 601 ensures maximum retention in the valve cavity during cycling. The use of 601 permits extended re-lubrication intervals when compared with Standard Service valve lubricants.

Valve Lubricant 601 is currently used to lubricate gate valves that are installed in a large range of oilfield production and drilling equipment. This unique ‘wide application’ capability of 601 allows the operator to standardise on one gate valve lubricant whilst ensuring maximum operational protection.

Valve Lubricant 601 has been field proven as a high performance sealant as well as a
lubricant. 601 may be injected into a leaking valve, providing long term sealing properties without actually hardening within the valve.

Valve Lubricant 501, an ‘Extended Temperature Range’ valve lubricant has been developed to provide comparable performance to 601 within a temperature range of -75°F to 350°F.

Where Oil & Gas is produced in cold climate regions low temperature pumpability is important, similarly valve shutdown temperatures can be extremely low. 501 permits lubricant mobility within the valve cavity at such temperatures, ensuring the valve can be opened or cycled within the rated torque range. For production conditions, 501 remains stable at operating temperatures up to 350°F.

A specially formulated, non hazardous synthetic cleaning fluid, 601 Cleaner, is available to remove both 601 and 501 during valve repair and refurbishment or to flush the valve during on-line operation.

Resistance of valve lubricants to hydrocarbon fluid

 The test involves a small sample of lubricant applied to a glass plate which is then placed within a container of hydrocarbon fluid. The results shown in the photo demonstrates the complete resistance to the fluid by Valve Lubricant 601. The effect of the hydrocarbon fluid on the Standard Service valve lubricant, GP Valve Grease, is to breakdown the base of the grease leaving only the solid lubricant in the base of the container. In the field, high frequency re-lubrication is required to maintain a cavity fill of Standard Service lubricant.

Plug Valve Lubrication

Plug Valve cross-section
 As detailed in the application photograph, Plug Valves are used as compact, shut-off valves in a range of production equipment downstream of the production tree. Plug valves are designed to operate with a sealant type lubricant.

When the lubricant is applied to the valve, it is distributed between the seating faces of the valve body and plug. The lubricant provides an integral sealing and corrosion preventative film. As the plug is covered by the lubricant over all surfaces, a smooth, controlled actuation is achieved over extended maintenance periods.

Valve Lubricant 601 is used for the lubrication and sealing of Plug Valves. 601 has been field proven to remain cohesive within the plug valve whilst providing the necessary sealing. This is unlike other sealants which may harden, resulting in leakage and exceptionally high actuation torques that can damage the valve stem.

The use of 601 in plug valves has allowed operators to standardise on one lubricant product on all wellhead and downstream equipment for the lubrication of gate and plug valves.

For operation temperatures to -75°F, Valve Lubricant 501 should be used.

Ball Valve Lubrication

Ball Valve cross-section

Seat & Seal arrangement cross-section
 The lubrication of a ball valve requires a different practice to the lubrication of either a gate valve or plug valve.

Field experience has shown that greases and sealants can cause severe problems with the seat / seal arrangement. If a non-leaking ball valve is lubricated with an adhesive grease / sealant, the floating spring loaded seats can become stuck within their seat pockets. When the ball floats due to a pressure differential across the valve, the seat / seal can no longer track the ball and leaking can occur.

A fluid type lubricant such as B70 or B70S, should be used to routinely flush and lubricate the valve. The fluid does not disrupt the operation of the seat / seal arrangement.

B70 is a standard service ball valve lubricant.
B70S is a synthetic ball valve lubricant designed to provide enhanced resistance to hydrocarbon fluids and gases, sour service, CO2, acids and completion fluids.

For leaking ball valves, 601 should be injected, which acts as a sealing compound without hardening in the seal arrangement.

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