DS-MAR23-PG47_Layout 1 17/03/2023 12:03 Page 1


HYDRAULICS & PNEUMATICS


Designing a high flow safety valve


BS&B Safety Systems has developed a safety relief valve that offers numerous benefits…


S


afety relief valves have, for centuries, served as a vital line of protection against excessive overpressure that, if left


unaddressed, can cause considerable damage to industrial processes – including equipment failure and process upset, along with secondary hazards arising from an uncontrolled release of pressurised fluid. The valves are designed to automatically open when the force exerted by the pressure reaches a setpoint to rapidly discharge the fluids. Once the overpressurisation has dissipated, the valve recloses, conserving the remaining fluid. The industry has largely standardised around


the 90-degree flow path design outlined by the American Petroleum Institute (API). This standardised approach requires a drop in pressure inside the valve before it discharges fluid from the exit nozzle. To ensure proper performance, the orifice diameter at the inlet side is smaller than the nominal valve size, with an outlet diameter that is larger than both. A two by three-inch traditional API configuration safety relief valve will be designed with either a 0.785” diameter H orifice or a 1.287” diameter J orifice at its inlet and a three-inch outlet, for example. “While it may be convenient for the purposes of


standardisation, other approaches to safety relief valve design are possible while meeting industry codes and standards such as those published by The American Society Of Mechanical Engineers (ASME),” commented Geof Brazier, managing director, BS&B Safety Systems, Custom Engineered Products Division. “The traditional 90-degree standardised configuration has the unintended consequence of limiting the amount of flow that is possible.”


A new ideA So, BS&B had an


idea: What if the safety relief valve was an inline device, with outlet and inlet connections that were the same size and an inlet orifice diameter to match the inlet connection? “With an inline


design, the flow moves in a straight line and doesn’t have to change direction,” said Brazier. “The design allows for a


certain amount of flow expansion, but we don’t


have nearly the same level of MARCH 2023 dESIGn SolUtIonS 47


turbulence inside the valve, which increases the capacity of the device,” By having the inlet diameter match the


nominal size of the valve, there is more flow [capacity]. The valve can also be more compact, lighter in weight, and requires smaller size – and therefore less expensive – piping. The result is simplified installation and a lower total cost of investment. To address the need for increased flow, BS&B


has introduced the IDV Safety Valve, a self- reclosing safety pressure relief valve that functions the same as a traditional safety relief valve but with an inline configuration rather than the traditional angle body configuration. According to the company, the inline


configuration allows for up to three times the capacity of a conventional valve. The smaller the nominal size, the greater the capacity benefit from the IDV Safety Valve. This new technology enables customers to achieve the same overall outcome as a traditional valve. Furthermore, the increased capacity allows engineers and operators to optimise their pressure safety systems and, in many applications, reduce the piping configuration (line size) by one or more nominal sizes.


design


The IDV Safety Valve is compact and lightweight


and can be installed using ANSI/ASME B 16.5 and international


flange connections. Mounting can be either horizontal or vertical, adding


to the flexibility of application for this design. The set pressure levels are independent of backpressure, meaning the valve is suitable for variable backpressure applications. The valve can be combined with an optional


integrated rupture disk at the inlet and/or outlet. The combination of a rupture disk device with a safety relief valve has many benefits arising from valve isolation to the normal process conditions including optimal leak tightness, increased operating pressure, extended valve life, and reduced valve maintenance. The IDV has already been installed in over


10,000 processes worldwide, making it an established alternative to the safety relief valve that meets the same codes and standards.


bS&b Safety Systems www.bsbsystems.com


SICK’S Hollow-SHaft EnCodErS opEn Up UnIvErSal CompatIbIlIty


SICK has unveiled its next-generation family of large-bore hollow-shaft incremental encoders, the SICK DGS80. An innovative design concept has opened up versatile integration possibilities for the DGS80 across industrial automation applications, aided by a radically-streamlined specification process and easy installation. The DGS80 spans a broad range of shaft diameters up to 42mm, all within an extremely


compact and rugged IP65-rated 81mm diameter housing. Starting with standard 30mm or 42mm diameter bores, the shaft size can be reduced with specially-designed insulated collets to ensure a secure connection to the application. SICK’s new large bore hollow-shaft encoder family gives end-users and machine builders the


confidence of universal machine compatibility while stocking minimal inventory. The DGS80 is also ideal for AC asynchronous motor feedback applications, capable of measuring speeds up to 3,600 revolutions per minute, with a resolution of up to 8,192 pulses per revolution. The plastic collets also offer the advantage of isolating the bearings from the motor current, ensuring long encoder life. Installation time is kept to a minimum by a choice of two slotted encoder stator couplings that


enable users to bolt the encoder at the right position onto any machinery. Designed to Nema motor frame standards, the stator couplings also facilitate flexible mounting to the drive shaft of an AC motor. Once mounted on a shaft, the DGS80’s clamping ring makes it easy to tighten the encoder in place using a single set screw. The SICK DGS80’s broad supply voltage range of 5V to 30V, for either HTL and TTL outputs,


facilitates integration into most machine controls and eliminates the need to choose between different voltage ranges. The temperature range of the DGS80 extends from -25˚C to 85˚C to cover many industrial applications. A choice of cable and connector options: M12, MS10pin, M23 and Cable, together with a range of six encoder resolutions, is sufficient to ensure wide-scale compatibility.


SICK www.sick.com


FEATURE


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56