Products — APTD Inc.

Highlights

Custom-designed CSPE boots with heavy-duty brass zipper and double zipper flaps
Install replacement boots in less than an hour, without disassembling the valve actuator
Supplied to Praxair, Air Liquide, Air Products, Linde, Air Gas, Matheson, and others
Cryogenic service valve boot assemblies include all parts required for a complete cold box installation of any size

Benefits

Custom solution for each installation, laid out with CAD software to the client's specifications
Pattern development uses a plotter for a perfect fit, even where a valve extension or pipe is not concentric with the casing cut-out
Constructed of synthetic rubber (CSPE) — UV resistant, indefinite lifespan even under cold box cryogenic frost conditions
Split collars enable size standardization of conical valve boots across different valve extension diameters
Boots and transition joints accommodate axial/lateral displacement from cooldown, and vibration from fans, blowers, or turbine ducting

The Assembly

Available individually, or as complete kits

A complete assembly kit can include:

Conical valve bootCustom CSPE, brass zipper

Brass zipper & flapDouble zipper flap supplied as standard

Split collarBored to valve extension OD

SS band clamps5/8 in. worm drive

Cold box bulkhead ring

Carbon steel, stainless steel, or aluminum — supplied where one does not already exist on the cold box casing.

Joint tape / sealant

Permanently tacky, synthetic thread reinforced butyl rubber sealant for collar joints and casing-to-bulkhead-ring joints.

Sealant tape2 in. or 1 in. width

Target Industries

Where APTD assemblies are installed

Air separation

Custom ASU cold box valve and pipe boots for producers of oxygen, nitrogen, argon, and hydrogen.

Cold box upgrades

Replacement boots to upgrade cold boxes built by Praxair, Air Liquide, Air Products, Linde, Air Gas, and others.

Duct transition joints

Custom duct transition joints for pulp and paper, sawmill, smelters, wastewater treatment, LNG plants, and diesel refineries.

Installation

Built to fit the casing and the valve extension

Boot to cold box casing

Valve and pipe boots install in either the vertical orientation (cold box roof) or horizontal orientation (cold box wall), attached to the casing one of two ways:

Standard with Ring Collar Boot — installed over a ring penetration (cold box bulkhead ring) protruding from the casing, secured with SS band clamps over the boot collar.
Witches Hat with Brim Boot — clamped flush against the casing, secured with a flanged ring over the boot brim.
Where a standard conical boot is desired and no bulkhead ring exists, one can be fabricated using rolled angle.

Boot to valve extension

Two options are available:

Band clamped directly to the valve extension outer diameter.
Band clamped to an aluminum collar bored to suit the valve extension OD — this permits boot sizing standardization across installations.

Full dimensional options — conical/concentric, conical/eccentric, cylindrical, and special transition styles, with or without split collar — are listed on the Documents page.

Why Retrofit

An old, damaged boot puts the whole cold box at risk

A damaged valve or pipe boot lets cold box purge gas escape and atmospheric moisture enter. That moisture freezes to form cold box "icebergs" — ice buildup that displaces and eventually breaks piping. Replacing an aging boot is a low-cost way to avoid a much costlier repair.