Seal failure in Waxy 65 Hydrocarbon.

[shyamshins]

Dear Sir,

I am facing seal failure is WAXY 65 hydrocarbon.

Seal is John Crane Type 2609 with flushing Plan 52 & 21 with 3mm orifice

First seal was leaking from Inboard & level of barrier fluid was observed rising. So syphon pot was drained & barrier fluid was bought to normal level & pump was put in operation. Again seal was found leaking from I/B side with rise in barrier fluid level.Also Outboard seal started leaking & drops were observed between gland & sleeve. Leakage rate was 5 drops per minute from O/B. At the same time syphon pot level was also found rising but it was very very less i.e. 1mm rise observed in sight glass of syphon pot. Previous leakage observed was 35mm in 24Hrs.

Now the leakage rate is reduced from both O/B and I/B of seal, but what can be seal failure reasons?

Below is the Process Data :

Process fluid : Waxy 65
Suction Press : 2.16 Kg/cm2
Disch. Press : 10.16 Kg/cm2
Process Temp. : 172 Deg Celcius.
Pump operation is continuos.

Temp observed in Plan 21 line from cooler to seal inlet is 105 Deg celcius.

Kindly suggest what can be seal failure reasons.

 

[gyaneshwarp]

In Plan 52 , liquid between the Inboard seal faces are process liquid. In the beginning till proper bedding in of the faces take place there is a chance of seal leakage. After sometime normally it reduces.

I suggest instead of Plan 52 if you go for Plan 53 A, you may not face similar problem.

 

[shyamshins]

How could Plan 53A help in arresting leakage of seal instead of existing plan 52.
Plan52 is used as barrier fluid will not mix with process fluid WAXY 65, as waxy 65 is a flammable hydrocarbon & process requirement is barrier fluid should not entre process fluid.

It's been 25 days seal is leaking but leakage rate has decreased.

Can I know what is waxy 65?

Pls explain how 53A pressurized plan would help.

 

[gyaneshwarp]

In Plan 53 A compatible barrier fluid is used. the barrier fluid is to be selected by user.

the reason why Plan 53 A will help is - the inboard seal will get lubrication from barrier fluid, instead of process fluid.