You can easily set for a pump / line what job types you can assign it to. This optimises the pump selection when creating a new job to only show the pump / line's that are capable of doing that job.
This helps with utilisation of your fleet by job types and reduces the need to use a pump/line for a job that it is not the best costed utilisation.
Go to Settings < Units

Click 'Edit' for the relevant Pump.
Complete the relevant details:
Enter Name, assign unique Username (so it can be identifiable on the schedule)
Enter Unit Details; Select the Job Types it can perform, capture any additional unit information (if you have set these up in Custom fields)
Click 'Save Unit'.