Analyzer Shelters

IPE Engineering Practice IPE-EP-12-7-2

Document number: IPE-EP-12-7-2 · Section: 12 — Instruments and Controls

SCOPE

This Practice defines the requirements for walk–in analyzer shelters.
Any deviation from this Practice shall be approved by the procedure described in EP 1–1–3.

2.0 REFERENCES

The following codes and standards shall be considered as part of this Practice. All documents shall be the latest editions in force on the date of issuance of this Practice.

STANDARDS AND PUBLICATIONS

IPE Engineering Practices
EP 1–1–3 Deviations to IPE Engineering Practices EP 5–2–3 IPE Piping Standards EP 12–7–1 On–Line Analyzers EP 13–2–1 Electrical Detail Design and Construction Practice
NFPA Codes
70 National Electric Code
APl Practices
RP 500 Classification of Locations for Electrical Installations in Petroleum Facilities

DEFINITIONS

Contractor - Company or business that agrees to furnish materials or perform specified services at a specified price and/or rate to the Owner.
Manufacturer - The recipient of a direct or indirect purchase order for materials and/or equipment. In this context, a direct order is one issued to a manufacturer by a contractor or the Owner. An indirect order is one issued to a manufacturer by a vendor (recipient of a direct order) for materials, fabricated components, or subassemblies.
Owner - Inflection Point Engineering, LLC
Owner’s Engineer - A Inflection Point Engineering, LLC appointed engineer.
Purchaser - The party placing a direct purchase order. The purchaser is the Owner’s designated representative.

GENERAL

Unless otherwise specified by the Owner’s Engineer, the analyzer shelter shall be supplied as a completely assembled package suitable for installation on a concrete pad or structural steel platform.
All analyzers, sample systems, and associated equipment shall be mounted and interconnected with all necessary utilities and accessories.

All equipment including tubing, wiring, and supports shall be installed so as not to interfere with the operation, maintenance, or removal of the analyzers, sample systems, and related items.
The walls and ceiling shall have insulation with a minimum thermal resistance of R-4.3.

BASE

The steel supporting base shall be fabricated from standard AISC shapes using ASTM A36 steel. The base design shall be sized and arranged for proper strength and durability to withstand the loads/forces resulting from shipping and lifting the completely assembled shelter with all equipment in place. Deflection during lifting shall not exceed 0.25 inches per 10 feet. Unless otherwise specified by the Owner’s Engineer, the base should be hot dip galvanized.
All members shall be joined by continuous weld.
The base shall have four removable lifting/jacking devices attached to and extending beyond the parallel to the base perimeter.

FLOOR

A Shelter floor may be specified by the Owner’s Engineer. When specified, the floor plate shall be a minimum 3/16 ASTM A36 steel material firmly bolted or welded to the base. The floor loading design shall be rated not less than 200 pounds per square foot, unless other specified by the Owners Engineer. Unless otherwise specified by the Owner’s Engineer, the floor shall be hot dip galvanized diamond pattern plate.
The floor shall be sufficiently flat and reinforced to provide stable support for the equipment bases as well as a smooth walking/rolling surface.

WALLS

The exterior walls shall be self framing 18 gauge galvanized steel panels with 3 inch interlocking ribs or 3 inch iso–polyurethane foam encapsulated in minimum 3/16 inch Class I fire-retardant fiberglass with an internal 18 gauge galvanized steel stud framework.
Internal walls shall be 18 gauge galvanized steel sheet or fiberglass
Unless otherwise specified by the Owner’s Engineer the exterior and interior wall shall be painted with white polyurethane enamel.
Unless otherwise specified by the Owner’s Engineer, the exterior wall panels and framing shall be designed to withstand wind loading up to 100 miles per hour.

DOORS

The access door shall be 36 by 84 inch minimum size.
Each door shall be seamless construction. Hinges shall be type 304 or 316 stainless steel, 10 gauge minimum, with 1/4 diameter fixed pin. A minimum of three 4 inch by 4 inch hinges shall be used and the hinge leaves shall be mounted such that they are perpendicular to the face of the door when it is closed.

Doors shall be of 16 gauge galvanized steel or fiberglass, double wall construction, containing fire resistant insulation.
A panic bar assembly and a heavy duty automatic door closer shall be furnished on the interior of each door. All hardware, interior and exterior, shall be of stainless steel.
When windows are specified, glass shall be safety glass per ANSI Z97.1, have a minimum thickness of 1/4 inch, and be either full tempered or laminated with a interlayer of 0.015 inch minimum thickness, or 1/4 inch thick ”lexan” acrylic.

HEATING, VENTILATING, AND AIR CONDITIONING

A heating, ventilating, and air conditioning (HVAC) system shall be provided for the shelter. The HVAC system shall be fully self-contained and automatic, requiring no manual changeover for heating or cooling.
The heating system in the shelter shall be thermostatically controlled electric heater with a forced draft fan. It shall maintain approximately 60oF inside the shelter during the winter months. The cooling system in the shelter shall maintain approximately 80oF inside the shelter. Cooling coils shall be corrosion protected by coating.
Ventilation shall be continuous and provide both fresh air makeup and recirculation of inside air. The entering fresh cold air shall be blown across the heating coils in order to prevent cold draft in the shelter.
The fresh air inlet shall be filtered by a reusable, removable filter, suitable for heavy dust loading.
The HVAC system shall maintain a positive pressure of at least 0.1 inch water within the shelter with the door(s) closed. Ventilation air shall be exhausted from the shelter through barometric louvers that are weighted to maintain the required positive pressure. The exhaust louvers shall include a bug screen. A minimum of 6 air changes per hour shall be supplied by the HVAC system. HVAC system shall be designed to provide adequate ventilation per API 500, Section

4.6.2. The Owner’s Engineer shall approve the location and sizing of the louvers and ventilation.

Differential-pressure activated switches shall energize an amber flashing beacon to indicate that forced-draft ventilation has failed on shelters in Division 1 areas.

ELECTRICAL

The inside of the shelter shall be considered as adequately ventilated per API 500 Section

4.6.62. The electrical installation shall meet the requirements of EP 13–2–1.

Separate junction boxes shall be provided for AC power, analog and digital input/output, and digital communication network wiring.
Junction boxes shall be NEMA type 4x with stainless steel hardware. Penetrations into junction boxes shall be from the bottom and sides only with gasketed connections.
Terminal blocks shall be barrier type with tubular clamp connections. Terminal blocks shall be mounted on rails and installed in columns.
Each analyzer, the HVAC, and lights shall be provided with a separate electrical disconnect.

The shelter shall be provided with at least one hazardous area industrial power receptacle. The type and manufacturer shall be approved by the Owners Engineer.
Lighting fixtures shall be vapor tight with guards and suitable for Class 1, Group D, Division 2 areas unless otherwise specified by the Owner’s Engineer. Lighting shall provide a minimum of 30 foot candles of lighting at the floor.

PIPING AND TUBING

Utility headers shall be sized according to the required capacity with spare allowance. The minimum size for headers shall be 3/4 inch pipe.
All headers shall be sloped and have low point drains with valves. Headers shall have 20% spare connections with pipe plugs.
Pressurized vent headers to an enclosed pressuring relieving system (flare) shall have a check valve to prevent backflow.
Each header shall have an individual shut-off valve, except for an atmospheric vent.
Headers shall penetrate walls through bulkhead plates or sealed openings and terminate with NPT or flange connections.
Piping and tubing of this assembly shall terminate with bulk head unions (for tubing) or piping connections per EP 5–2–3, IPE Piping Standards.

CARRIER, STANDARD, CALIBRATION, AND FUEL CYLINDERS

Cylinders shall be secured with a cylinder rack attached to the shelter.
Cylinder regulators for chromatograph carrier or fuel gases shall be dual stage with a maximum delivery pressure of 100 psig, unless otherwise specified by the Owner’s Engineer.
Cylinder regulators for calibration or standard gases shall be dual stage with a maximum delivery pressure of 30 psig, unless otherwise specified by the Owner’s Engineer.

NAMEPLATES AND TAGGING

All connections, components, devices, analyzers, and related equipment in the shelter shall be identified with nameplates, tags, wire markers, or typed schedules.
Unless otherwise specified, all nameplates shall be laminated plastic with white engraving on black background. Warning nameplates shall be laminated plastic with white lettering engraving on a red background. Engraved lettering to be 1/4 inch high minimum for information nameplates and 3/8 inch high minimum for warning nameplates.
All nameplates shall be permanently attached with pop rivets, screws, or a silicon rubber adhesive.
All field connections (piping, and electrical), circuit breakers, valves, transducers, valves, transducers, analyzers, cylinder locations, and sample systems shall be clearly identified.
Field mounted items shipped loose shall be identified with stainless steel tags attached with stainless steel wire.

Sample bulkhead connections shall be identified with the corresponding analyzer tag number.
Utility headers and all header taps shall be identified with the corresponding service.
Power switches and circuit breakers shall be identified with the corresponding service.
Junction boxes and terminal blocks shall be identified.
All wires shall be identified with permanent wire markers.

INSPECTION AND TESTING

The Vendor shall provide test and inspect the shelter, piping, electrical, and tagging. A signed checklist shall be available for review by a IPE Inspector. The Vendor may use the checklist attached to this report.
When requested by the Owner’s Engineer, facilities shall be made available for a IPE Inspector to witness the inspection and testing. Facilities shall consists of a temporary office and phone.

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