For total isolation of storage vessels, valves are not totally reliable. Removing a section of piping or use of ine blinds is the only absolutely positive way to assure absolute issolation. The CONFINED SPACE should be isolate by blinding, by disconnecting and blanking all lines connected to the space.
 
In today’s world there are regulations and rules of the game of vessel isolation that must be lived with. Temperatures, Pressures, health & safety standards, release of chemicals to atmosphere, pollution control norms,safety of workers and above all employees themselves are monitoring their working atmosphere and rightly refusing to work in dangerous and unsafe conditions. Properly designed, installed and maintained line blinds can make life a little easier when faced with all these regulations.
 
Positive pipeline close-off is vital in many piping systems to assre safety of personnel working on downstream equipment. Particularly when flammble or toxic liquid or gases could seep past closure. When visible and positive proof of shutoff is necessary a lineblind defeats the visual inspection need to be certain that the line is blocked.

Risansi Online Blind is an unique system and an improvement over conventional paddle blind/figure eight/hammer blind/spectacle blind. It eliminates the need to spread the body flanges. The fixed ‘O’ ring is mounted on the seal carrier. A single activator screw perpendicular to the axis of the pipe, when rotated, slides a moveable inclined plane against a fixed inclined plane, allowing the seal carrier to move axially towards the spectacle plate thus tightening is completely, or away from the spectacle plate allowing the blind to be thrown / or the spectacle plate to be rotated on the slot. The open or closed position of the line is simultaneously indicated and is clearly visible.

Online Blind Open
In this picture the green coloured spectacle plate is tight. The solid part is seen visually indicating that the pipeline is open and full flow through the line is available.

Online Blind in Change position
Once the pipeline has been de-pressurized and drained the hand wheel is rotated giving clearence for the green coloured spectacle plate to be rotated. As shown in the picture the spectacle plate in between the open and close position.

Online blind Closed
In this picture the green coloured spectacle plate is tight. The part seen visually is hollow indicating that the pipe-line is closed and flow through the line is blocked totally.

Blinding Plates or spectacle plates (sometimes called Paddle Blinds or Figure Eight) have been in existence for many years and for good reason they are simple leak proof shutoff. A blinding plate or figure eight inserted between two gasketed companion flanges will provide an absolute dead shutoff. But they have maintenance problems. Refer Table-1.
 
Hammer Blinds have seals mounted on spectacle plate thus exposing them to the sun, and accidental mechanical damage. Due to change in temperature, expansion or contraction result in piping misalignment effecting alignment of spectacle plate and the seal. To spread the body flanges, bolts have to be turned one by one and the operator has to continuously jump over the line; which could be very cumbersome if the line size is very large. While tightening the bolts ‘gall’ or ‘freeze’ frequently occurs.

Once the pipeline has been de-pressurized and drained the hand wheel is rotated giving clearence for the green coloured spectacle plate to be rotated. As shown in the picture the spectacle plate in between the open and close position.

In this picture the green coloured spectacle plate is tight. The part seen visually is hollow indicating that the pipe-line is closed and flow through the line is blocked totally.

1) Open & Closed position readily visilble.
2) RISANSI ONLINE BLIND once mounted need not to be removed.
3) Spreading of pipe is not required.
4) Seal protected from accidental mechanical damage.
5) Seal protected from exposure to sun.
6) Seal ubaffected by piping misalignment
7) Seal can be changed ONLINE
8) Simple one man operation.
9) Fast & Easy Operation
10) Positive shutoff of liquids, slurries and gases.
11) All standard materials are readily available.
RISANSI ONLINE BLINDS are available in flanged/buttwelded connections.

Petroleum application -
Production and Refining Pipeline, Gas gathering (including sour gas service), CO2/well injection.
 
Processing applications -
Chemical, Synthetic, Rubber, Food & Beverage,Pulp & Paper
 
Slurry Aplications -
Cements Plants, Mining
 
Marine Applications -
Abroad ships and tankers, Terminals and storage
 
Installed in conjuction with an upstram valve it can be used in the most critical Application:
aboard oil tankers, ships, loading docks and barge services where cross contamination of cargo or accidental overbroad discharge assumes the proportions of a disaster; in the chemical and petrochemical plants, refineries and tank storage farms. Power houses install them upstream of equipment which requires frequent repairs, Steel mills, Cement industry, Sugar mill, Pulp & Paper industry all use blinds.

1) Blinding Plates or spectacle plates (sometimes called Paddle Blinds or Figure Eight) have been in existence for many years and for good reason they are simple leakproof shutoff. A binding plate or figure eight instead between two gasketed companion flanges will provide an absolute dead shutoff. But they have maintenance problems. Refer Table-1.
 
2) Hammer Blinds have seals mounted on spectacle plate thus exposing them to sun, and accidental mechanical damage. Due to change in temperature, expansion or contraction result in piping misalignment effecting alignment of spectacle plate and the seal. to spread the body flanges, bolts have to be turned one by one and the operator has to continously jump over the line; which could be very cumbersome if the line size is very large. While tightening the bolts ‘gall’ or ‘freeze’ frequently occurs.
 
3) RISANSI ONLINE BLIND is mounted on the pipe, the body flanges need not be spread plus the bolts are of increased diameter and tackwelded, hence the seal is unaffected by piping misalignment. The seals are mounted inrenally (protecting the from sun and accidental damage) yet they can be replaced ONLINE. the open or closed position of the line is simultaneosly indicated and is clearly visible because of which chances of accidents are totally eliminated AN IMPORTANT SAFETY FEATURE.