This article is about how to do pipe insulation with cold and hot method.
EQUIPMENT AND PIPE INSULATION PROCEDURE
(i) All insulation materials shall be stored, mixed, thinned and applied in accordance with the manufacturer’s printed instructions.
(ii) All conflicts between the method statement and manufacturer’s instructions shall be brought to the attention of Contractor for resolution.
(iii) Insulation material shall not be applied over wet surfaces.
(iv) Insulation material section shall be trimmed as required to achieve tight fit without voids.
(v) Fabricated or preformed insulation shall fit curvature of the surface to be insulated.
(vi) If applying single layer insulation other than hinged pipe covering the circumferential butt joints of each half section shall be staggered.
(vii) If applying multi layer Insulation material each layer shall be staggered to the longitudinal and circumferential joint of the layer beneath.
(viii) Each layer of insulation shall be held in place separately.
(ix) Insulation shall be applied as single layer for thickness less than 90mm.
(x) All insulation shall be free from cracks, voids and gaps. All cracks, voids etc greater than 3mm shall be refitted not filled.
(xi) Vessels and tanks shall be insulated with blanket insulation.
(xii) Installed insulation shall have the required permanent or temporary protection applied before the conclusion of days work.
(xiv) Insulation material shall be handled and disposed of in accordance with applicable federal, state, and local laws and regulations
(xv) SS piping & Equipment shall be insulated with SS wire mesh blankets to avoid bi – Metallic corrosion
(xvi) Piping’s, Equipment’s & Vessel shall be tested & inspected as required by relevant specification prior to installation of insulation.
(xvii) Removable or flexible type insulation shall be used in areas where access for frequent maintenance is necessary
(xvii) Name plates shall not be insulated and shall be attached with extended brackets to give adequate clearance for full insulation thickness.
Types of Insulation
1. Hot Insulation
The Hot insulation installation will cover the following two major categories in this Project
Hot Insulation for Piping & Hot Insulation for Equipment
Hot Pipe insulation Procedure for Piping
The hot Pipe insulation of piping shall have mainly 6 activities.
(i) All Pipe insulation materials shall be protected from rain and moisture.
(ii) Pipe insulation sections shall be trimmed as required to achieve close fit to avoid major void and gaps.
(iii) All hot piping insulation shall be done with mineral fiber (blanket/section)
(iv) All piping insulation with single layer less than or equal to 8” shall be installed by preformed pipe section.
(v) Sectional Pipe insulation shall be sized to eliminate gaps and voids between surfaces and the insulation.
(vi) Sectional Pipe insulation shall be applied so all end joints are staggered.
(vii) Pipe insulation shall be secured with SS wire or Bands spaced at max. 250mm.
(viii) For vertical piping Pipe insulation the support ring will install directly above all elbows, flanges or flanged valves. Additional support will install at every 6425 mm of uninterrupted length.
(ix) Elbow 4” and over shall be insulated with mitered cut.
(x) Pipe insulation shall terminate at a distance of (bolt length+25mm) flanges and valves occur.
Hot Insulation Procedure for Equipment
The hot insulation of piping shall have mainly 6 activities.
(i) All insulation materials shall be protected from rain and moisture.
(ii) Equipment insulation support ring, pins, clips and accessories shall be compatible with equipment material.
(iii) All hot equipment insulation shall be done with mineral fiber blanket.
(iv) Insulation on both the inside and the outside of skirts shall be equal to the shell insulation thickness.
(v) Insulation shall be sized to eliminate gaps and voids between Surfaces and the insulation.
(vi) Insulation materials shall be secured with bands every 250 mm maximum Centers.
(vii) For vertical equipment with skirts, insulation on bottom heads only shall be held in place by bands.
(viii) Insulation for instrument shall be applied in a way so that there is no interference with either the operation or function of instrument and allow all gauges.
(ix) Expansion joints shall not be applied on equipment having temperature up to 650◦ C.
(x) Insulation shall be terminate at a distance of (bolt length+25 mm) flanges and valves occur.
2. Cold Insulation
Cold insulation installation will cover the following two major categories in this article.
Cold Insulation for Piping & Cold Insulation for Equipment
Cold Insulation Procedure for Piping
The cold insulation of piping shall have mainly 8 activities.
(i) All insulation materials shall be protected from rain and moisture.
(ii) The thickness greater than 76 mm will be install by multi-layer insulation.
(iii) All cold piping insulation shall be done with cellular glass.
(iv) Insulation Up to 12” OD will secure by fiberglass reinforced tape.
(v) Insulation shall be sized to eliminate gaps and voids between Surfaces and the insulation.
(vi) Insulation Up to 36” OD from 12” will secure by 12 mm band.
(vii) Insulation over 36” OD will secure by 20 mm band.
(viii) Insulation securement shall be spaced on a maximum of 250 mm.
(ix) Protrusion through insulation of piping will be insulated for a minimum distance equal to 4 times of adjacent insulation thickness.
(x) Insulation thickness on protrusions shall be half of adjacent insulation thickness.
(xi) Insulation thickness on protrusions shall be 38 mm, if the half value of adjacent insulation comes less than 38 mm.
(xii) Vapor stops that seal the insulation to pipe shall be installed at all insulation terminations.
(xiii) Vapor stop shall extend a minimum of 50 mm from insulation termination point.
(xiv) Before the application of jacketing all insulated surface shall be sealed with vapor barrier sheet.
(xv) Vapor barrier sheet shall be installed without gaps or folds with 50 mm overlap.
Cold Industrial insulation Procedure for Equipment
The cold industrial insulation of equipment shall have mainly 8 activities.
(i) All industrial insulation materials shall be protected from rain and moisture.
(ii) The thickness greater than 76mm will install by multi-layer.
(iii) All cold equipment industrial insulation shall be done with cellular glass.
(iv) Industrial insulation Up to 12” OD will secure by fiberglass reinforced tape.
(v) Industrial insulation shall be sized to eliminate gaps and voids between Surfaces and the insulation.
(vi) Industrial insulation Up to 36” OD from 12” will secure by 12 mm band.
(vii) Industrial insulation over 36” OD will secure by 20 mm band.
(viii) Industrial insulation securement shall be spaced on a maximum of 250 mm.
(ix) Protrusion through industrial insulation on equipment will insulated for a minimum
distance equal to 4 times of adjacent industrial insulation thickness.
(x) Industrial insulation thickness on protrusions shall be half of adjacent insulation thickness.
(xi) Industrial insulation thickness on protrusions shall be 38 mm, if the half value of adjacent industrial insulation comes less than 38 mm.
(xii) Vapor stops that seal the industrial insulation to equipment shall be installed at all industrial insulation terminations.
(xiii) Vapor stop shall extend a minimum of 50 mm from industrial insulation termination point. Vapor Barrier Installation.
(xiii) Before the application of jacketing all insulated surface shall be sealed with vapor barrier sheet.
(xiv) Vapor barrier sheet shall be installed without gaps or folds with 50 mm overlap.
Weatherproofing Installation (INSULATION JACKETING)
(i) All external surface of insulation shall have a weather barrier finish to keep Insulation dry and provide mechanical protection.
(ii) All joints shall be fabricated with proper overlap and to prevent moisture penetration.
(iii) All joints shall be caulked with silicone sealant to stop moisture entry.
(iv) Screws if used shall not penetrate the vapor barrier in cold insulation.
Jacketing Procedure for Piping
(i) Jacketing for horizontal and vertical cylindrical piping shall have minimum 50 mm circumferential and longitudinal laps
(ii) The longitudinal lap on horizontal piping shall be between four o’clock and eight o’clock position to shed rain water.
(iii) On vertical piping, the upper course of jacketing shall overlap the lower.
(iv) On vertical pipes, upper course shall be supported by “S” clips.
(v) Jacketing shall be secured with stainless steel bands on appox. 300 mm centers.
(vi) Smooth sheet of 0.4~0.6 mm shall be used for boxes.
(vii) Two pieces elbow shall be installed up to 3”.
(vi) The jacketing shall be secured with self-tapping screws.
Jacketing Procedure for Equipment
(i) Jacketing shall be applied with 50 mm overlap on all seams.
(ii) On vertical vessels, provide a minimum of two corrugations overlap.
(iii) On vertical vessels, the upper course of jacketing shall be supported by S-clips, on max. 450 mm centers.
(iv) Jacketing shall be secured with bands on 450 mm centers and one in each
Circumferential lap (Preventing sliding “U” clip shall be applied on max. 1220 mm distance).
(v) Jacketing shall be secured with stainless steel bands on approx. 300 mm centers.
(vi) Smooth sheet of 0.4~0.6 mm shall be used for boxes.
(vii) Sheet metal screws shall be installed on longitudinal joints at 150 mm centers (not required in circumferential laps).
(vi) The jacketing shall be secured with self-tapping screws.
TML PLUG INSTALLATION
(i) The use of inspection plugs is applicable only for hot insulated surface of Piping/Equipment
(ii) Removable insulation plug shall be provided to permit on-stream ultrasonic inspection when required by the operating proponent.
(iii) The inspection plugs shall be vapor tight.
(iv) The material for removable insulation plug shall be NDT Inspection Plug(Aluminum/EPDM) OR equivalent.
(v) All hot piping insulation up to 6” shall be installed by 1.5” inspection plug.
(vi) All hot piping insulation 6” and more shall be installed by 2.5” inspection plug.
(vii) All hot equipment insulation shall be installed by 5” inspection plug.
(viii) Removable insulation plug shall be provided to permit on-stream ultrasonic inspection when required by the operating proponent.
(ix) Subcontractor will make the inspection window only after finishing the markings of contractor representative.
DRESS UP INSULATION WORK
(i) Prior to the actual dress-up insulation work schedule, insulation subcontract should
prepare and deliver on site all required insulation materials including ancillaries and
sealants.
(ii) Properly store all said materials on a pallet near the equipment(s) and cover with
tarpaulins. If required, secure using tie-wires on nylon rope.
REPAIR WORK PROCEDURE
(i) Damage to insulation weather jacketing shall be repaired immediately if the damage can result in additional damage to the insulation due to water leakage into the system.
(ii) If permanent repair is not immediately practical, temporary repair of damaged weather jacketing shall be required.
(iii) Damaged insulation shall be replaced if the nature of the will adversely affect the thermal performance of the system.