ENGINEERING SPECIFICATION
Vertical LFG Wellhead Assembly
(Quick-Change Orifice Plate Wellhead with Precision Fine Tune Control Valve)
PART 1— GENERAL
1.1 SCOPE
The manufacturer shall furnish one or more wellheads as described below for use in a landfill gas collection system.
1.2 PROCESS DESCRIPTION
A landfill gas wellhead shall be installed in each vertical landfill gas well. The wellhead shall be used to measure as a component in the landfill gas collection system to measure and regulate landfill gas flow at each well.
1.3 MANUFACTURER
The manufacturer shall have a minimum of 15 years experience providing manufactured goods for landfill gas well applications. Proof of this experience must be submitted with bid.
The manufacturer’s standard, published warranty shall cover 100% of material and workmanship for a minimum of one year or longer.
The manufacturer shall have a local factory-trained agent (located within 300 miles of the site) and shall have a minimum of five factory-trained OSHA certified technicians available for installation or site assistance. The name and address of the local agent must be submitted with bid.
The manufacturer shall maintain a toll-free service and troubleshooting telephone line, operating 24 hours/day, 365 days/year. Proof of this capability must be submitted with bid.
The manufacturer must be capable of shipping all standard equipment within ten working days of receipt of order.
The manufacturer shall have a minimum of 20 factory staff available for site-specific questions on system design, technical support and customer service.
1.4 SUBMITTALS
The following additional documentation shall be submitted for approval prior to construction:
Product data for selected model(s), including physical dimensions, weight, rated flow range, materials of construction, general specifications, accessories, and warranty coverage.
PART 2 — PRODUCTS
2.1 GENERAL
The Wellheads shall be Precision Quick-Change Orifice Plate Wellheads as manufactured by QED Environmental Systems, Inc. in the following model configurations and flow rate ranges:
Model ORP115 – 1-1/4” Diameter, 0 – 40 CFM Flow
Model ORP215 – 2” Diameter, 0 – 125 CFM Flow
Model ORP315 – 3” Diameter, 30 – 300 CFM Flow
Wellhead design shall meet the following requirements and must be able to operate under the following conditions:
· All components designed specifically for landfill gas applications such that the wellhead will be withstand exposure to vacuum, weather, ultraviolet light, and typical landfill gas constituents
· The wellheads shall incorporate a removable orifice plate system with various sized orifices that meet ASME MFC-3M-2004 design criteria
· Will incorporate a Fine Tune Flow Control Valve (QED Model CV2000 or QED Model CV3000)
· Will have Schedule 80 PVC piping throughout
· Will be air tight and leak free
2.2 EQUIPMENT DESIGN REQUIREMENTS
2.21 Wellhead standard product design shall include a gas flow control valve, removable orifice plates, pressure measurement, temperature measurement and gas quality access ports with the following features and specifications:
· The Wellhead shall incorporate a quick-change housing that will allow the operator to change orifice plates in less than 20 seconds.
· The Orifice Plates will be sharp edged and shall be constructed of 1/16” laser-cut stainless steel with a flow coefficient of 0.62.
· Each plate shall have an easy-to-read tab with the orifice size clearly and permanently indicated. The orifice size must be read without removing the plate from the housing.
· Each Wellhead will be provided with a set of orifice plates ranging in size as follows:
· 1-1/4” wellheads shall include 0.26”, 0.50”, 0.75” and 0.95” orifice plates
· 2” wellheads shall include 0.40”, 0.50”, 0.75”, 1.00”, 1.25” and 1.40” orifice plates
· 3” wellheads shall include 1.25”, 1.75” and 2.10” orifice plates
· Each orifice plate will have an eccentric hole to prevent water damming in the horizontal piping in horizontal wellhead configurations.
2.2.2 Wellhead Control Valve shall be constructed of Schedule 80 PVC pipe and stainless steel with the following features and specifications:
· The Valve shall have a rising stem design for easy identification of valve position.
· The Valve housing shall include an indexed scale of 0 - 100 for identifying and recording valve position settings.
· The Valve stem shall have a ¾” stainless steel shaft with coarse threads for long term durability and linear flow adjustment.
· The Valve handle shall be made of stainless for long term durability. No plastic handles subject to breaking are allowed.
· The Valve will provide near linear adjustment of gas flow throughout 10 full turns of valve movement for precise flow control.
2.2.3 The Stabilizer Well Cap shall be configured for use in either a 6 inch or 8 inch well casing with the following features and specifications:
· The Cap shall be appropriate for a (6 or 8) inch well casing.
· The Cap will be constructed of heavy walled, high-density polyethylene for durability and weather resistance.
· The Cap will support the use of a (2 or 3) inch landfill wellhead.
· The Cap will include an integral, molded, support ring that will align and stabilize the gas wellhead.
· The Cap will include a flexible coupling to join the cap to the well casing, and separate flexible coupling to secure the landfill gas wellhead.
· The Cap will have a minimum of 5 threaded ports. Three ports will have threaded compression fittings for accommodating down-well pump tubing.
· The Cap will include a stainless eyelet to pump support line, and a mounting bracket for an air filter/pressure regulator.
· The Cap will be bright yellow for increased field visibility
Section 6002: Quick-Change Orifice Plate LFG Welllheads
REV 050613 Copyright 2013 QED