FREQUENTLY ASKED QUESTIONS

Q WHAT HAS BEEN THE PRACTIE ALL OVER THE WORLD?

A CONDENSER & HEAT EXCHANGERS ARE DESIGNED WITH ALLOWANCE OF PLUGGING 10% TUBES. ONCE 10% PLUGGED THEN RE-TUBE 100% IGNORING THE FACT THAT 90% TUBES ARE STILL OPERATIONAL – OLD PRACTICE.

Q WHAT IS THE BENEFIT OF CTI SHIELD / SEAL?

A TUBE FAILURE COMMON IN NATURE AND NORMALLY IT IS LOCATED WITH IN FEW INCHES AT THE TUBE INLET END. CTI SHIELD CAN BE USED TO PROTECT THE DAMAGING LENGTH OF TUBE TO PROTECT IS FROM DAMAGE OR RESTORE THE DAMAGED TUBE AT LESS COST AND WITH IN LESS TIME.

Q HOW LONG IT TAKES TO INSTALL CTI SHIELD / SEAL?

A NORMALLY IT TAKES 10 TO 12 HOURS TO INSTALL 700 TO 1000 SHIELDS.

Q ARE THOSE SHIELDS READILY AVAILABLE?

A THEY ARE CUSTOMIZED. THEREFORE IN MOST CASES THEY NEED TO BE MANUFACTURED WHICH REQUIRE 7 TO 8 WEEKS.

Q HOW LONG SHIELD IS GONNA LAST?

A CTI SHIELD IS ALWAYS MADE FROM MORE NOBEL METAL YET MAINTAIN GALVANIC COMPATABILITY. ASSUMING 1ST TUBE LEAK APPEARED FIVE YEARS AFTER IN OPERATION AND IF YOU RE-TUBE WITH SAME TUBE MATERIAL, IT WILL AGAIN FAIL IN SIMILAR TIME FRAME. CTI SHIELD WILL AT LEAST LAST FOR THAT TIME FRAME. PRACTICALLY, IT STAYS AT LEAST TWICE THE TUBE FAILURE TIME. BECAUSE A STRONGER MATERIAL SHOULD WITH STAND ON THOSE OPERATING PARAMETER ALMOST FOR EVER IF FAILURE MECHANISM IS IDENTIFED CORRECTLY.

Q CAN WE CALL THIS IT A PERMANENT SOLUTION?

A IT IS RELIABLE LONG TERM REPAIR / RESTORATION TECHNIQUE TO PROTECT THE FAST WEARING LENGTH OF TUBE. NO DOUBT, YOU GOT TO RE-TUBE ONE DAY. IT IS JUST LIFE EXTENSION

PROGRAM. IF YOU WERE TO RE-TUBE IN TEN YEARS TIME, YOU MAY USE THE SAME TUBES FOR ANOTHER TEN YEARS OR MORE.

Q TUBES ARE NOT LEAKING BUT TUBE TO TUBE-SHEET JOINT. WHY AND CAN THIS ALSO BE REPAIRED?

A NORMALLY, LEAKS APPREAR FROM TUBE TO TUBE-SHEET JOINTS SINCE EROSION CAUSE JOINT LOOSENING. CTI SHIELD IS INSTALLED TO RESTORE THE TUBE TO TUBE-SHEET JOINT AND ALSO PROTECT THE DAMAGING LENGTH OF TUBE SINCE EACH END OF SHIELD IS EXPANDED.

Q HOW CAN YOU ENSURE SEAL IN THE TUBE SINCE THERE IS NO TUBE-SHEET BUT ONLY TUBE WHICH IS DAMAGING ALREADY?

A ANY ONE CAN EXPAND AT TUBE SHEET. IT IS ENSURED BASED ON VAST EXPERIENCE AND KNOWLEDGE OF CTI SHIELD SEALING ABILITY AND THE SKILL BASED ON CALCULATED EXPANSION TO GAIN SEAL AT DEEP END WITHOUT DEFORMING THE TUBE. MORE OVER, LENGTH OF SHIELD IS BASED ON DAMAGING LENGTH TO PASS THE DAMAGING LENGTH AND EXPAND AT RELATIVLY HEALTHEIR TUBE AREA.

Q CAN SHIELD BE INSTALLED IN U-TUBES?

A SHIELD CAN BE INSTALLED IN STRAIGHT PORTION OF TUBE. IF U-BUNDLE IS FAILING AT STRAIGHT END WHICH IS MOST LIKELY. BUT THE U-BEND IT SELF CANNOT BE REINFORCED BY CTI SHIELD.

Q WHAT IS THE COST COMPARISON?

A CTI SHIELD /SEAL CAN SAVE YOU MONEY AND TIME. NORMALLY SHIELD CAN SAVE UPTO 50% OF THE COST OF RE-TUBING.

Q WHAT IS THE MATERIAL OF CTI SHIELD / SEAL?

A SHIELDS ARE ALWAYS MADE FROM DIFFERENT ALLOYS DEPENDING UPON THE EXISTING TUBE MATERIAL AND SWEARITY OF DAMAGE.

Q WHAT IS THE LENGTH OF CTI SHIELD / SEAL?

A SHIELDS CAN BE PROVIDED IN ANY LENGTH DEPENDING UPON THE LENGTH ON DAMAGE. SO FAR, WE HAVE INSTALLED EIGHT

(08) FEET LONG SLEEVES.

Q WHAT IS THE AMOUNT OF IMPACT DUE TO FLOW AREA REDUCTION?

A SINCE IT IS HEAT EXCHANGING EQUIPMENT, IT IS BETTER TO EXPLAIN THE OVER ALL IMPACT IN TERMS OF HEAT TRANSFER LOSS. IF WE INSTALL THIN WALL SHILEDS IN ALL TUBES, IT WILL NOT BE SIGNIFICANT. FOR YOUR UNSERSTANDING, IT WILL NOT BE MORE THAN COUPLE OF TUBES PLUGGED.

Q WHAT IS THE THICKNESS OF CTI SHILED / SEAL?

A NORMALLY THE THICKNESS OF CTI SHIELD IS AROUND 0.5mm (0.020”).

Q WHAT ABOUT THOSE TUBES SUFFER FROM CORROSION ATTACK TO THE ENTIRE TUBE LENGTH?

A CTI OFFER FULL LENGTH TUBE LINERS. LINERS ARE MADE TO UPGRADE THE MATULLURGY TO IMPROVE EROSION / CORROSION RESISTENCE. WE TRANSFORM EXISTING TUBE INTO BIMETALIC TUBE ON SITE.

Q WHAT IS THE THICKNESS OF FULL LENGTH LINER?

A CTI LINERS ARE SIMILAR IN THICKNESS AND MATERIAL WITH CTI SHIELD / SEAL.

Q HOW FAST CAN IT BE INSTALLED?

A NORMALLY 200 TO 400 HUNDRED LINERS CAN BE INSTALLED IN JUST 12 HOURS.

Q HOW MUCH HEAT TRANSFER LOSS WILL CAUSE THIS?

A 10 TO 12% HEAT TRANSFER LOSS IS DEFINATE. IF THIS IS ACCEPTABLE FOR THAT PARTICULAR UNIT, THEN IT IS DEFINITELY AN ECONOMICAL SOLUTION TO UPGRADE THE MATERIAL IN LEAST TIME.

Q CAN SHIELDS OR LINERS BE INSTALLED IN SEAL WELDED TUBES?

A YES BOTH SHIELDS AND LINERS CAN BE INSTALLED IN THOSE TUBES WHICH ARE ROLLED & WELDED. BOTH SHIELD & LINERS ARE EXPANDED BEHIND THE SEAL WELD AT THE TUBE ROLLING

AREA.

Q WHAT ABOUT ONLY SEAL WELDED TUBES?

A SORRY, SHIELD OR LINERS CANNOT BE INSTALLED SINCE WE NEED TO GAIN JOINT SEAL BY ROLLING AT TUBE SHEET.

Q CAN WE USE SHIELDS OR LINERS IN BOILER TUBES?

A NO, BOTH SHIELDS OR LINERS CANNOT BE USED IN THOSE TUBES WHERE THERMAL SHOCK IS EXTENSIVE.