Groth 5000 User Manual

Installation, Operation and Maintenance Manual for

Models 5000 and 5100

Free Vents

©2009 Groth Corporation

IOM-5000

Rev. A 12072

Issue: 03/14/2012

I. INTRODUCTION

Relief vents are used on liquid storage tanks and other process vessels or systems to prevent
structural damage due to excess internal pressure or vacuum.

Storage tanks are pressurized when liquid is pumped in, compressing the existing vapor or when
rising temperatures cause increased evaporation or expansion of existing vapor. Conversely, a
vacuum condition may be created when pumping out or due to falling temperature. To prevent
tank damage, vapor must be allowed into or out of the tank at specified pressure/vacuum
conditions. The volume rate of venting depends upon the tank size, volatility of the tank contents,
the pumping rates and the temperature. Refer to API Standard 2000, ISO 28300, or local
regulations for the procedures to determine venting requirements.

A relief vent must be carefully maintained by a qualified valve technician. It should only be
assembled under clean conditions, preferably in a service shop environme nt. Carefully read and
understand this manual before installing or attempting to repair a vent.

For information not contained in this manual, please contact:

Page 2 of 4

Groth Corporation

13650 N. Promenade Blvd.

Stafford, TX, 77477 USA

Phone: [phone]

Fax: [phone]

www.grothcorp.com

II. DESIGN AND FUNCTION

The Groth Model 5000 Series are high flow capacity free vents designed to be used on tanks
containing non-volatile liquids and on vent pipe extremities. These devices contain no moving
parts and allow storage vessels to freely in-breath or out-breath to the atmosphere.

III. SAFETY WARNINGS

This section is an overview of safety guidelines that should be followed during the installation,
operation and maintenance of Groth Pressure/Vacuum Relief Valves. To understand the context of
these instructions and warnings, it is necessary to completely read and understand the contents of
this manual.

The purpose of a relief vent is to prevent excessive pressure or vacuum in a tank or process
system. The vent must be designed for the proper Maximum Allowable Working Pressure (MAWP)
and flow requirements of the system. Consult API Standard 2000, ISO 28300, or local regulations
for tank protection sizing procedures. An improperly specified or functioning relief vent may result
in structural damage to the tank or system, and can cause severe personal injury or death.

If the vent has been exposed to process vapors while in service, observe all plant procedures and
Material Safety Data Sheets (MSDS) for the products in the system when inspecting or servicing
the vent. Take appropriate safety precautions regarding eye protection, respiration and skin
contact.

IV. INSPECTION AND STORAGE

The relief vent is carefully packaged to prevent damage or contamination during shipping. Inspect
all equipment when it is received; report any damage to the carrier immediately. The vent should
be protected during handling and storage. Keep all the ports plugged to prevent intrusion of foreign