1. purpose
1.1 This specification defines for the contractor the minimum requirements for installing mineral wool insulation (hereinafter called rock wool).
2. scope
2.1 The contractor shall furnish all labor, tools, and equipment required to pack the low temperature process equipment jackets with rock wool insulation in accordance with the contract drawings and specifications. Also included is the removal of temporary shipping (equipment and pipe) supports from inside the process equipment jacket. This information will be listed on a project-specific document issued by Air Products or its cold box fabricator.
3. RELATED DOCUMENTS
3.1 Air Products Engineering Documents 4WCB-50002 Mineral Wool for Cold Box Insulation 4WCE-600700 Construction Safety
4. GENERAL
4.1 It is extremely imperative that provisions be made by the contractor to prevent any water or other liquids from entering crossovers or the equipment jackets while the panels are off and during the full time that the equipment jacket interiors are subject to atmospheric conditions. This may be accomplished by the use of tarpaulins having water- and fire-resistant qualities.
4.2 The contractor shall consult the Air Products representative when a cold box is designated as having a “Stressed Panel Cold Box Design” or when there is a sign on the side of the cold box indicating as such. In these cases, there are specific entry requirements and procedures that need to be reviewed and implemented before entering or creating accessways into a cold box structure. The sign or decal on the cold boxes will state: “WARNING: Do not remove or cut into the panels of this cold box without consulting the plant operating manual for specific guidelines and restrictions.”
5. MATERIALS
5.1 The contractor shall use rock wool which will be supplied by Air Products and which conforms to 4WCB-50002.
6. WORKMANSHIP
6.1 The contractor shall employ only labor which has been qualified by training and experience to capably perform the specific activities required to accomplish the work in a satisfactory manner.
7. SAFETY
7.1 When handled, rock wool will emit particulates into the air. These particulates can be irritating to the respiratory system and the eyes. Therefore, goggles shall be worn at all times. When inside enclosures where open rock wool is being handled or packed (for example, inside the cold box) and where airborne particulate concentrations could be high, a North 7600 Series with N-7500-83 cartridges or equal respirator shall be used. Respirators shall be changed as required by filter clogging.
7.2 It is the contractor’s responsibility to train their employees/visitors to comply with these and all other federal, state, or local regulations pertaining to the packing of rock wool. Proper documentation of all such training shall be maintained on site and copies given to the on-site Air Products representative.
7.3 Any employee using an air-purifying or a particulate protection respirator must be fit-tested before its use. Site personnel will normally be fit-tested and trained/retrained once a year or once per jobsite, depending on the job’s duration. Records of employee or visitor respirator fit testing, assignment, and training shall be kept.
7.3.1 There must be no interference with the mask seal in order to get a good fit. Temple pieces on glasses, facial hair, stubble, or the absence of dentures will all prevent a good seal, depending on respirator design. Small beards or mustaches which fit inside the seal area and do not lift the respirator from the face, or sideburns outside the mask seal area are permissible. Bearded employees whose facial hair interferes with the mask seal either must shave before being fit-tested, or not be used to perform this type of work.
7.4 Most respirators create additional resistance to breathing. A medical screening must be performed to ascertain that person’s ability to perform the required extra physical effort. This screening shall be documented.
7.5 If a vacuum truck is used to assist in rock wool removal, a North Model Number 3007 respirator or equal is required both inside the cold box and for personnel working on rock wool removal outside of the cold box. The contractor shall verify that the cold box is properly grounded to prevent build-up of static electricity that could shock personnel during vacuuming operations.
7.5.1 If a vacuum truck is not used in rock wool removal, employees directly involved in removal using hands-on tools, bagging or sweeping wool, or employees working in a confined space using the removal process shall wear a full-face, air-purifying respirator equipped with dust filters (upper limit 0.05 milligrams per cubic meter dust). North 7600 Series respirators with N-7500-83 cartridges or equal are acceptable. Other employees involved with tasks in the general area should still wear disposable respirators as described in paragraph 7.5.
7.6 Three points must be noted about using a full-face respirator: The face shield does not fog up, as goggles do. They will restrict peripheral vision more than goggles. If a person wearing a full-face respirator wears prescription glasses, a new set of glasses must be purchased that will fit inside the slots provided in the respirator.
7.7 The contractor shall also provide for a means of protecting the skin of workers from exposure to the rock wool and its particulates, as it will also cause irritation.
7.8 The contractor shall provide adequate ventilation in cold boxes, ducts, and crossovers during the packing operation.
7.9 The contractor shall assure that a qualified person remains outside the structure to act as a safety attendant for the workers inside. The confined space requirements will be determined on a case-by-case basis.
7.10 Smoking shall not be permitted within the space to be packed once packing has started.
7.11 Contractor shall consult 4WCE-600700 for other safety information that relates to this work scope.
8. EQUIPMENT
8.1 The contractor shall provide and maintain all tools and equipment in first-class condition and in sufficient quantities to assure successful performance and completion of the required work.
9. INSTALLATION PROCEDURES
9.1 The contractor shall exercise extreme caution to prevent damaging the process components, piping, and instrumentation elements. Any damage caused directly or indirectly by the contractor’s labor, tools, or equipment shall be repaired or replaced at no extra cost to Air Products. The contractor shall maintain a pressure of 0.34 bar g (5 psig) with a source of dry, oil-free air on all circuits in the process equipment.
9.1.1 Particular care shall be taken when packing the area between pipes, equipment, around the jacket face, and under box frame members. Also around valve bodies, stems, inside vessel skirts, near valve seal boots, pipe sleeves, and when in the vicinity of thermocouples.
9.1.2 Each circuit shall be valved off from the compressed air source after the 0.34 bar g (5 psig) level has been attained. Each circuit pressure shall be monitored during packing by a low pressure gauge and alarm. Any leaks created in any circuit by the workers will show up as a loss in pressure, and an alarm will sound. The packing operation shall be stopped, the circuit shall be depressurized, and the leaks shall be repaired by the contractor at no additional expense to Air Products. After the leaks have been satisfactorily repaired and pressure tested, the circuits shall again be pressurized and the packing operation shall be resumed.
9.1.3 The contractor shall check continuity through both leads of all thermocouples of the box as the work of packing the box is progressing. When an area where a thermocouple is located is fully packed, a continuity check shall immediately be made to confirm that it is not “opened” or damaged.
9.2 The contractor shall clean the interior of the process equipment jacket before starting to place mineral wool, and shall exercise precaution to prevent entrance of any foreign material during and after completing the packing operation. The interior of the process equipment jacket must be kept free of all foreign material including (but not limited to) wood, paper, rags, oily waste, and metal scraps.
9.2.1 Bags of insulating material shall be lowered carefully and not dropped. A daily record of all insulating-material containers taken into the space shall be kept to ensure that all empty bags are removed.
9.3 The contractor shall not proceed with the packing of rock wool in the process equipment jacket until all piping and equipment have been pressure tested, and approval to proceed with packing has been given by the Air Products representative.
9.4 The contractor shall pack the rock wool in successive layers, approximately 150 mm (6 in) thick, and compacted to a density of 225 kg/m3 (14 lb/ft3) minimum to 240 kg/m3 (15 lb/ft3) maximum, as described in 4WCB-50002. Voids will not be tolerated except for the void space between the top of the insulation and the bottom of the vessel inside vessel skirts. As packing progresses, the contractor shall remove all temporary shipping supports that have been identified with red or yellow paint or by the Air Products field representative.
9.4.1 The location of the temporary shipping supports will be determined by Air Products. This information will be listed on a project-specific shipping support record issued by Air Products or its cold box fabricator. It will be this contractor’s responsibility to remove the temporary supports and complete the appropriate information on this form. The form, when completed, must be turned over to the Air Products representative.
9.4.2 The contractor shall pack rock wool on the inside of all vessel skirts to a minimum depth of 450 mm (18 in) above the floor plate before proceeding with packing the remainder of the column box or process equipment jacket.
9.5 Installation of complete bags—intact by merely removing the paper or outer wrapping—will not be allowed, as this tends to leave voids between the contents of the individual bags. The bags must be broken up and packed to the required density described in this specification.
9.6 The contractor shall remove cold box panels that are tack-welded to the cold box frame to allow access for entry and rock wool installation. Panels shipped tack-welded have been identified on the contract drawings. Once the rock wool installation is completed and accepted by the Air Products representative, the contractor will replace and seal-weld the cold box panels. Cold box removable (bolted on) panels may be removed by the contractor during the packing of the lower levels and replaced prior to packing at the level where the bolted panels exist. The contractor must ensure that the proper gasketing material is used or replaced when replacing the bolted panels.
9.6.1 If additional access openings are required, the contractor must contact the Air Products representative and/or Cold Box Engineering for approval, before any cutting.
9.7 The contractor shall keep the rock wool dry and clean at all times. If this material becomes wet or contaminated, it shall be removed and replaced by the contractor. Once rock wool becomes wet, it cannot be reused.
9.8 The contractor shall ensure that all voids are filled. This includes, but is not limited to, instrument tubing and supports, structural members, permanent equipment and piping supports, process piping, and valve bodies.
9.9 The crossovers between cold boxes shall be insulated in accordance with this specification and the above applicable installation paragraphs. The panels may be attached in place by others; consult the contract drawings for specific details.
9.10 The cold box or free-standing distillation column shall be plumbed before grouting and packing the box with rock wool. The plumbness of the column may be influenced by the density of the rock wool around the column. Precision checks of the alignment of the column shall be performed by the contractor, as required by the Air Products representative.
9.11 The contractor shall keep a daily log of the amount (number of bags) of rock wool packed and the elevations reached during each shift.
9.12 Where steel framework is attached close to cryogenic piping and supports, the area between the outside steel and box panels shall be packed with rock wool or blanket insulation.
9.13 The contractor shall give special care to tight areas around pipe supports, under piping, valves, equipment, and cold box frame diagonals. These areas should be hand-packed to assure there are no voids in these areas.
9.14 The contractor is responsible for repacking any areas where frost spots develop, when it can be determined that the rock wool was not packed to the proper density or where voids were left.
10. INSPECTION AND APPROVAL
10.1 The Air Products representative shall have the right at any time, during or immediately after packing the rock wool, to test the packed density of the rock wool to establish that it has been installed in a satisfactory manner. A wooden probe 50 mm x 100 mm (2 in x 4 in nominal) of sufficient length may be utilized as an aid in determining whether the rock wool has been packed to the proper density. The criteria for acceptance shall be that the probe will not penetrate into the rock wool surface more than 75 mm (3 in) when the probe is thrust several times with the force of 133 to 155 Newtons (30 to 35 pounds). This force is equal to that which can be exerted by an average person. A definite resistance to penetration should be noted. Should the probe show any sign of penetration without much effort being exerted, further packing is required to achieve the required density.