This custom designed carbon steel constant measures 19 5/8″ wide, by 59 1/2″ tall, by 52 1/8″ long. It is designed for a 500 lb. load with a total travel of 17 1/2″. The support frame was increased in height to meet a large take-off of 59 1/2″. The constant spring will be used to support piping in an oil refinery.
The constant spring hangers are manufactured from A36 carbon steel and have custom 4-bolt pipe clamps due to heavy loads. The dimensions are 40″ length x 18″ width x 85″ height and are designed for a 1,784 lb. load with 10″ of travel. The constants will be used to support radiant inlet manifolds and have a unique paint applied due to the highly corrosive condition. The entire pipe hanger assembly went through load and travel testing prior to shipping.
This initial order included PT&P’s field services division testing and recalibrating four constant spring supports not manufactured by PT&P. A preliminary inspection of the original constants revealed deformations in the spring coil housing. This is indicative of defective coils; therefore, before any load tests were conducted, inspection windows were cut into the spring coil cover to confirm the initial hypothesis (Figure 2). Inspection of the coils revealed complete deterioration with broken and missing sections of the spring. Subsequent inspections of the remaining three assemblies illustrated similar failures. The original constants were then disassembled (Figure 3) to determine the feasibility of replacing only the coils while utilizing the original frame/cam components.
The original spring coils were different in spring rate, length, and diameter than any standard PT&P coils; therefore, multiple coils were required to duplicate the overall function of the existing coils. Using multiple coils also required modifications to the existing frames. In an effort to expedite the overall delivery schedule, entirely new constant springs were manufactured in one week (Figure 1). The four new constants measure 53″ long, 13″ wide and 86″ tall. They have a 18-3/4″ diameter spring coil with a coil housing of 20-1/2″ diameter. The new constant assemblies are designed for an operating load of 13,332 lb., travel of 13″ upward and 2″ downward for a combined total travel of 15″. A load test throughout the total travel range was performed on each constant.
These constants are manufactured from A36 carbon steel and measure 11″ x 29″ x 61″. Total weight of each constant is 430 lb. The loaded capacity is 2,160 lb. and the maximum travel is 15″. Standard load and travel test were done to ensure quality and performance. The turn around for this product was four days.
PT&P designed and manufactured forty PTP 200- type “E” constant hanger assemblies with pipe sizes ranging from 36” to 62” for an oil refinery in Canada. These constant hanger assemblies are designed to support and allow vertical movement of the field pipe during thermal expansion. The constants have a load capacity of 2800 lbs. to 9200 lbs. and a 3”-7” travel range. To assure quality, standard load testing was performed on the constants prior to shipping. The assemblies’ components consist of a constant load hanger, a rod and a clamp. The constants are fabricated from ASTM A36 carbon steel and the rod and clamp were manufactured from ASTM A240, Gr. 304 stainless steel.
Piping Technology & Products, Inc. designed and manufactured 70 horizontal, C-type constants for a furnace application located in Venezuela.
The sizes of the Figure 200 constants ranged from 32 to 64, with a total travel of 4.5 to 10.5, and loads varying from 1,149 to 5,149 pounds. The constants are provided with a custom designed PT&P Figure 270, which consists of a double lug horizontal traveler versus a single lug. Within the horizontal travel, the constants are designed to handle 8 of horizontal movement and support a rod that remains vertical throughout pipe movement.
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