Stock Jet Geometry for Gap Roll Formers

SKU: C-867Duration: 24 Minutes

Pay-per-view (PPV) format perfect for individual users.

Get immediate access to this interactive eLearning course online. Must be used within 30 days, expires 48 hours after launch.

Language:  English

$39
 Add to Cart

Great for in-person classroom training or as an alternative to DVD.

Includes printable documents and Convergence Video Player for Windows systems. Content expires after 1 year.

Language:  English

$299
 Add to Cart

Great for trainers or groups who need unlimited online access to multiple courses. Available in two ways:

Headboxes (Tissue) Series (Details)
Includes 2 courses for $99/year.

Tissue Library (Details)
Includes 31 courses for $699/year.

Ideal for corporate licensing and high volume users.

Get Convergence courses into your current LMS to track and report employee training. Or contact us to learn more about the advantages of licensing our courses with the Convergence LMS.

Get Pricing Info

 Need help deciding? Compare delivery formats.

Course Details

Specs

Training Time: 24 minutes

Compatibility: Desktop, Tablet, Phone

Based on: Industry Standards and Best Practices

Languages: English

A hydraulic headbox installed on a modern tissue machine is designed to deliver a uniform, low consistency stock stream to the nip between the two forming fabrics. Several geometries of the stock jet, including jet length, jet angle, and jet impingement, have a large effect on sheet formation and sheet quality. This module covers some common headbox adjustments and other equipment settings that can affect the stock jet geometry.

Learning Objectives

At the end of this module, you will be able to:

  • Describe the purpose of the headbox in the tissue making process
  • Define the terms "jet length," "jet angle," and "jet impingement"
  • Identify the jet length, jet angle, and jet impingement in a stock jet diagram
  • Describe the impact of stock jet geometry and sheet formation on the appearance and strength properties of the sheet
  • Describe the effects of the slice opening and fan pump speed on stock jet geometry

Key Questions

The following key questions are answered in this module:

Which stock jet geometries are important for gap roll formers?
Jet length, jet angle, and jet impingement are all important.

Why is it important to have a short free jet length?
A short free jet length reduces the time available for the fibers to reflocculate before the sheet sets, and if there are multiple layers, it minimizes mixing between the different layer furnishes.

What is jet angle?
The jet angle is the angle between the stock jet and the outer forming fabric.

What is jet impingement?
The jet impingement is the percentage of the jet thickness that impinges on the forming roll.

What variables can affect stock jet geometry and sheet formation?
The gap between the breast roll and forming roll, slice opening, fan pump speed, and jet-to-wire ratio all affect sheet formation and the optimum stock jet geometry.

Sample Video Transcript

Below is a transcript of the video sample provided for this module:

One more sheet attribute that can be affected by headbox operations is fiber orientation in the sheet. The overall or average orientation of the fibers in the sheet is largely determined by the relative speeds or velocities of the stock jet and the forming fabrics. Normally, the relationship between the two speeds is expressed as the the jet to wire ratio, where wire refers to a forming fabric. In short, if the stock jet's speed is significantly lower or higher than the fabric's speed, the fibers will align more in the machine direction. With more fibers aligned in the machine direction, the sheet will tend to be stronger in the machine direction. Sheet formation and sheet appearance are also affected.

Customer Q&A

I would like to have several employees take multiple courses. How can I set that up?

We're in the process of making bulk course and multiple user purchases easier. But for now, you can order multiple courses and contact us with details on who you'd like to assign courses to. We can set up each user's training plan and make sure everyone gets the eLearning assignments they need.

Can I get a free full-length preview of a course to see what this course covers?

While we do our best to offer details on course contents, we don't normally offer full-length previews. But please contact us with more details for a better understanding of what your organizaton needs and how we can help.

Do I get a certificate when I complete a course?

Yes. All of our courses allow you to print a completion certficate upon successfully passing the integrated test at the end of each eLearning course.

How do I log in to take a course that I have already paid for?

You'll receive an email with login details moments after you purchase your pay-per-view (PPV) course. Just click the login link and enter the user name and password provided.

Do you have courses in different languages?

Yes. While all of our courses are originally produced in English, we develop many courses in a growing number of languages, including Chinese, Dutch, German, Italian, Japanese, Korean, Polish, Portuguese, Russian, Spanish, Tamil, and Thai. Available languages are normally displayed in the Course Details section on each course page.
Added to Cart! Click here to view your cart.
Training Software
eLearning Courses
Solutions
Convergence Training Newsletter

Stay up to date on our products and offerings and get safety, compliance, and training administration tips in our free monthly newsletter.

© Convergence Training | Privacy Policy