Inflatable Rubber Bladders

[rishmael]

In need of a high temperature (300 degree farenheit)inflatable bladder. Initial bladder dimensions are 2 3/4" OD, 2 1/8" ID and 15" length. Bladder needs to inflate to 5 1/2". Pressure rated for 1500 to 2000 psi. This bladder will be run inside a steel tubing in a downhole oilfield application. This is a prototype tool and other larger sizes for bladders will be needed.

 

[tomaspin]

Hi,

Rather than looking for bladders, I think you should be talking to manufacturers of hydraulic/pnematic accumulators, who should be able to supply a packaged unit, with the correct bladder material to withstand the operating conditions.
I hope this helps

Tom

 

[ElastomerXpert]

If you really need long-term heat resistance to 300 deg F, you will find only a limited number of elastomers will serve. If the rubber only sees the heat and pressure (from air or inert gas) and you don't need oil resistance, EPDM might do the job OK. If the bladder is going to inflate/deflate a lot, which means a lot of flexing, then you need flex resistance as well. Silicone will take the heat, but maybe not the flexing. An engineer in the rubber business will want to know a lot more details about the function. And by the way, if this is not going to lead to orders for a serious number of bladders, it'll be hard to get anyone interested in the requisite development work. Good luck.

R J Del Vecchio
Technical Consulting Services
(consultant in Applied Rubber Technology)

 

[johnchrc]

An accumulater comapny won't have any idea how to help as your application is unique to the oilfield packers.

The bladder has a 2:1 expansion ratio which is not a difficult probelm for the elastomers used for these products.

Your problem is the pressure at 300F and preventing extrusion. The bladder by itself will not do that. You need a means of reinforcing the bladder to prevent the bladder from squeezing out under pressure. See Baker, TAM and Weatherford for examples. They use slats and wire weave. For 300F only a slat design will work.

There is no such thing as long-term inflatable packer. for long term the packrs are cement inflated, in which case the bladder is no longer an issue. This comes with it's own set of problems.

 

[johnchrc]

As far as a material, HNBR is your best bet. It has good elongation properties, temperature capability, resistance to normal oila nd gas well fluids and can handle some H2S.