Heat sealer - AbsoluteAstronomy.com

A heat sealer is a machine

Machine

A machine manages power to accomplish a task, examples include, a mechanical system, a computing system, an electronic system, and a molecular machine. In common usage, the meaning is that of a device having parts that perform or assist in performing any type of work...

used to seal

Seal (mechanical)

A mechanical seal is a device which helps join systems or mechanisms together by preventing leakage , containing pressure, or excluding contamination...

product

Product (business)

In general, the product is defined as a "thing produced by labor or effort" or the "result of an act or a process", and stems from the verb produce, from the Latin prōdūce ' lead or bring forth'. Since 1575, the word "product" has referred to anything produced...

s, packaging, and other thermoplastic

Thermoplastic

Thermoplastic, also known as a thermosoftening plastic, is a polymer that turns to a liquid when heated and freezes to a very glassy state when cooled sufficiently...

materials using heat

Heat

In physics and thermodynamics, heat is energy transferred from one body, region, or thermodynamic system to another due to thermal contact or thermal radiation when the systems are at different temperatures. It is often described as one of the fundamental processes of energy transfer between...

. This can be with uniform thermoplastic monolayers or with materials having several layers, at least one being thermoplastic. Heat sealing can join two similar materials together or can join dissimilar materials, one of which has a thermoplastic layer.

Types of heat sealing

Hot bar sealers- have heated tooling kept at a constant temperature. They use one or two heated bars which contact the material to heat the interface and form a bond. The bars have various configurations and can be covered with a release layer.
Continuous heat sealers- (also known as Band type heat sealers) utilize moving belts over heating elements.
Impulse heat sealers- have heating elements (one or two) of Nichrome
Nichrome
Nichrome is a non-magnetic alloy of nickel, chromium, and often iron, usually used as a resistance wire. Patented in 1905, it is the oldest documented form of resistance heating alloy. A common alloy is 80% nickel and 20% chromium, by mass, but there are many others to accommodate various...

placed between a resilient synthetic rubber and a release surface of film or fabric. The heating elements are usually not heated. When the materials are placed in the heat sealer, they are held in place by pressure. An electric current heats the heating element for a specified time to create the required temperature. the Jaws hold the material in place after the heat is stopped, sometimes with cooling water: this allows the material to fuse before stress can be applied.
Hot melt adhesive can be applied in strips or beads at the point of joining. It can also be applied to one of the surfaces during an earlier manufacturing step and reactivated for bonding.
Hot wire sealing - involves a heated wire that both cuts the surfaces and joins them with a molten edge bead. This is not usually employed when barrier properties are critical.
Induction sealing
Induction sealing
Induction sealing, otherwise known as cap sealing, is a non-contact method of heating a metallic disk to hermetically seal the top of plastic and glass containers. This sealing process takes place after the container has been filled and capped.-How it works:...

is a non-contact type of sealing used for inner seals in bottle caps.
Ultrasonic welding
Ultrasonic welding
Ultrasonic welding is an industrial technique whereby high-frequency ultrasonic acoustic vibrations are locally applied to workpieces being held together under pressure to create a solid-state weld. It is commonly used for plastics, and especially for joining dissimilar materials...

uses high-frequency ultrasonic acoustic vibrations to workpieces being held together under pressure to create a weld.

A type of heat sealer is also used to piece together plastic side panels for light-weight agricultural

Agriculture

Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...

buildings such as greenhouse

Greenhouse

A greenhouse is a building in which plants are grown. These structures range in size from small sheds to very large buildings...

s and shed

Shed

A shed is typically a simple, single-storey structure in a back garden or on an allotment that is used for storage, hobbies, or as a workshop....

s. This version is guided along the floor by four wheels.

Seal quality

Good seals are a result of time

Time

Time is a part of the measuring system used to sequence events, to compare the durations of events and the intervals between them, and to quantify rates of change such as the motions of objects....

, temperature

Temperature

Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...

and pressure

Pressure

Pressure is the force per unit area applied in a direction perpendicular to the surface of an object. Gauge pressure is the pressure relative to the local atmospheric or ambient pressure.- Definition :...

for the correct clean material.
Several standard test method

Test method

A test method is a definitive procedure that produces a test result.A test can be considered as technical operation that consists of determination of one or more characteristics of a given product, process or service according to a specified procedure. Often a test is part of an experiment.The test...

s are available to measure the strength of heat seals. In addition, package testing

Package testing

Package testing or packaging testing involves the measurement of a characteristic or property involved with packaging. This includes packaging materials, packaging components, primary packages, shipping containers, and unit loads, as well as the associated processes.Testing measures the effects...

is used to determine the ability of completed packages to withstand specified pressure or vacuum. Several methods are available to determine the ability of a sealed package to retain its integrity, barrier characteristics, and sterility.

Heat sealing processes can be controlled by a variety of quality management system

Quality management system

A quality management system can be expressed as the organizational structure, procedures, processes and resources needed to implement quality management.-Elements of a Quality Management System:# Organizational structure# Responsibilities# Methods...

s such as HACCP, statistical process control

Statistical process control

Statistical process control is the application of statistical methods to the monitoring and control of a process to ensure that it operates at its full potential to produce conforming product. Under SPC, a process behaves predictably to produce as much conforming product as possible with the least...

, ISO 9000

ISO 9000

The ISO 9000 family of standards relates to quality management systems and is designed to help organizations ensure they meet the needs of customers and other stakeholders . The standards are published by ISO, the International Organization for Standardization, and available through National...

, etc. Verification and validation

Verification and Validation

In software project management, software testing, and software engineering, verification and validation is the process of checking that a software system meets specifications and that it fulfills its intended purpose...

protocols are used to ensure that specifications are met and final materials/packages are suited for end-use.

Types of heat sealing

Seal quality

See also

General references